JP7583481B2 - Wind turbine generator units and their associated equipment - Google Patents

Description

The present invention relates to a wind power generator unit and an assembly facility thereof, and in particular to a wind power generator unit using a cylindrical coil that can handle everything from light breezes to strong winds, and which is compact enough to enable multiple units to be connected together, and an assembly facility thereof.

Natural energy (renewable energy) such as wind and solar power is being used as a clean energy source, but although wind power can generate electricity even on cloudy or rainy days, it is known to have the drawback that wind force and direction are not constant. Therefore, in order to increase the efficiency of wind power generation, it has been known to switch the coil circuit in wind turbines.

JP 2000-197392 A JP 2011-114938 A

In Patent Document 1, the coil circuit is switched to accommodate batteries. However, it is not a coreless type generator, and it is desirable to have an output voltage that is easy to obtain. Furthermore, the switching is not multi-stage compatible.

Patent Document 2 uses a coreless type wind turbine generator in combination with a solar power generator, and switches between multiple DC-DC converters to increase the power generation efficiency of the wind turbine generator. Wind power generation can range from a light breeze to a strong wind, so two-stage switching alone is not enough to cope with it, so multiple DC-DC converters are also used for coil circuit switching. This allows it to cope with a wide range of winds, from light breezes to strong winds, and further maximizes power generation efficiency. In this way, Patent Document 2 also requires two-stage switching, and requires boost equipment such as multiple DC-DC converters. The coil shown in this precedent example is a flat type.

As described above, wind strength varies from light to strong winds, and although the equipment that receives the wind responds by controlling it with a gearbox or brakes, the two-stage switching has limitations in terms of responding to the wide range of winds.

Therefore, the present invention proposes a wind turbine unit and its associated equipment that can efficiently convert wind from light breezes to strong winds into electricity and improve battery performance.

In order to solve the above problems, the wind power generator unit of the present invention is characterized by any one of the following.
(1) A wind power generator unit comprising: blades that rotate when exposed to wind; a generator having a rotating shaft that supports the blades; and a structure that incorporates the generator, wherein the generator comprises at least a non-rotating cylindrical coil body, an inner yoke arranged cylindrically opposite the cylindrical coil body with a gap therebetween, and a permanent magnet arranged on the inner yoke's surface facing the cylindrical coil body, wherein the cylindrical coil body is formed by stacking a plurality of phases each consisting of a plurality of coil units , and further comprising an inter-coil switching device that switches the connection pattern between the coil units to a plurality of stages selected from combinations of series, parallel, and series and parallel depending on the difference in the rotational force of the blades associated with wind speed.

また、前記円筒状コイルはコアレス、スロットレスから選ばれることを特徴とする風力発電機ユニットである。 (2) In the above (1), the coil switching device is a wind power generator unit characterized in that it switches so that the system efficiency calculated by the following formula based on the power change obtained according to the wind speed becomes a maximum value .

The wind power generator unit is also characterized in that the cylindrical coil is selected from the group consisting of a coreless coil and a slotless coil.

Switching so that the system efficiency is maximized means, in other words, that the coil body of the generator is formed from multiple coils and equipped with a switch that switches between three or more types of connections between the coil bodies, and by switching the connections between the coils, a single wind power generator has multiple power generation systems with different system efficiencies. In other words, the present invention is characterized in that, in a generator that switches between three or more systems by switching the connections between the coils, it switches to a system that maximizes the system efficiency for the wind speed. This applies to both increasing and decreasing wind speeds.

This switching method was discovered by the inventor through experiments on how to switch systems when adopting a system with high power generation efficiency. Furthermore, the inventor discovered that if the timing of system switching is such that power generation efficiency is maximized rather than voltage is kept constant, then by finely switching the maximum system efficiency, it is possible to approach the characteristics of a DC-DC converter and ultimately replace the DC-DC converter with a coil connection switching board. This invention is based on an insight he gained while performing finely-tuned switching of wind power generation with three or more stages.

(3) A wind power generator unit comprising: an air passage, a generator located on the air passage, blades attached to the outer circumferential rotating part of the generator on the air passage, and a frame body that houses the generator and the blades, the air passage penetrates the front and rear parts of the frame body, so that the generator and the blades are located on a through passage connecting the front and rear parts, the generator has a shaft fixed to the frame body, and comprises at least a non-rotating cylindrical coil body, an inner yoke arranged cylindrically opposite the cylindrical coil body with a gap therebetween, and a permanent magnet arranged on the inner yoke's surface facing the cylindrical coil body, the cylindrical coil body is formed by stacking a plurality of phases each consisting of a plurality of coil units , and further comprises an inter-coil switching device that selects a connection pattern between the coil units from a combination of series, parallel, series and parallel depending on the difference in the rotational force of the blades associated with the wind speed and switches between multiple stages . The frame body corresponds to the structure that houses the generator in (1) above (the same applies hereinafter in this application).

他は前記（２）の通りである。 (4) In the above (3), the coil switching device is a wind power generator unit that switches so that the system efficiency, calculated by the following formula based on the power change obtained according to the wind speed, becomes a maximum value .

The rest is as described above in (2).

(5) In (3) or (4) above, the frame has six rectangular faces, and the distance between the front and rear portions is shorter than each side of the front and rear portions, resulting in a box with a slim appearance.

(6) In (3) or (4) above, the height of the front and back portions is 1 to 2 m, and the width of each peripheral surface is less than half the height of the front portion.

(7) In (3) or (4) above, an outer yoke is provided that is located outside the cylindrical coil body in addition to the inner yoke, and the outer rotating part (circumferential surface) of the generator to which the blades are fixed forms a casing of the generator, and the casing is integrated with or serves as the outer yoke.

(8) In any of (3) to (7) above, it is desirable that an air collecting section is formed on both the front portion and the rear portion, and that the blades are formed symmetrically in both directions toward both openings of the air passage.

(9) In any of the above (3) to (8), it is desirable that wind collecting sections are formed on both the front and rear sections, and that the blades are formed symmetrically toward both openings of the air passage. Furthermore, when the blades are placed inside the air tunnel, they have an approximately rectangular parallelepiped appearance and are smart with no protruding parts.

(10) Note that types that use cylindrical coils are typically coreless generators, but slotless generators also fall into this category. In both cases, the cylindrical coil does not rotate, and the permanent magnet and magnet yoke rotate. However, in the coreless type, the outer yoke (which can also be called a coil yoke) also rotates, while in the slotless type, the outer yoke is non-rotating. In both cases, there is no iron core in the center, meaning they are air-cored, which reduces inductance and therefore surge current.

Incidentally, although the term "coil unit" is used in this specification, one coil unit may be a single coil of the same specifications (same material, dimensions, and diameter) or multiple coils connected in series. However, the number of coils constituting each coil unit must be the same. For example, if n coils with the same number of turns are connected together to make one coil unit, then if there are three coil units, then 3 x n coils will be used.
The wind power generator unit assembly of the present invention is characterized in that:

(11) Install a plurality of wind power generator units as described above in (1) to (9) in an area exposed to the atmosphere, and provide each wind power generator unit with a wireless LAN transceiver for communicating the operating status of the unit, and also provide a storage facility to which the generated power output of each wind power generator unit is transported.

(12) In (11) above, the installation area is selected from the rooftops of buildings, verandas, balconies, fences, bridges, road medians, roadsides, vacant lots, farmland, parks, beside railway tracks, and beaches.

(13) In the above (11), the wind turbine generator units are arranged vertically and/or horizontally connected so that the openings of the wind tunnels are aligned with the direction of the front portions.
Furthermore, if the blades are arranged vertically (vertical axis type), it is also effective to extend the generator's rotating shaft upward and add more blades upward, rather than using a box-shaped unit.

Each phase of the coil section is composed of the same number of coil bodies, and the multiple coil bodies have a coil group A in which the connections between the coil bodies have a multi-stage switching pattern of three or more stages selected from combinations of series, parallel, series and parallel switching, and fine wire B made of a conductor that is thinner than the coil wire that constitutes the coil group A and has no contact points along the way. Switching is performed between using the coil group A with the fine wire B connected to it and using only the coil group A without the fine wire B, and automatically switching between three or more stages according to the wind speed, which is particularly effective for dealing with very light breezes.

In addition, the coil portion is formed by winding wire material several times for each phase to form the coil body, and a plurality of such coil bodies are connected and stacked to form a cylindrical coil body, and a conductor is drawn out from each of the coil bodies and connected to a coil switching board, and the coil switching board is provided with a switch circuit, which effectively performs multi-stage switching of three or more stages of patterns by switching selected from series, parallel, and series and parallel combinations of the coil bodies.

Each phase of the coil section is composed of the same number of coil bodies, and the multiple coil bodies have a coil group A in which the connections between the coil bodies have a multi-stage switching pattern of three or more stages selected from combinations of series, parallel, series and parallel switching, and fine wire B made of a conductor that is thinner than the coil wire that constitutes the coil group A and has no contact points along the way. Switching is performed between using the coil group A with the fine wire B connected to it and using only the coil group A without the fine wire B, and automatically switching between three or more stages according to the wind speed, which is particularly effective for dealing with very light breezes.

The present invention has the effect of always using the maximum (i.e. best) system efficiency (= power generation efficiency) by switching the connections between the coil units to three or more stages. This is achieved by configuring the coil section of the generator with multiple coil units and configuring the connections between the coil units to be switchable to three or more stages. Also, if the coil section is made cylindrical, it becomes easier to arrange and form the coils. In addition, the power generation efficiency is improved by gradually responding to a wide range of wind forces from light breezes to strong winds, charging is possible even in light breezes, and battery failure can be avoided in strong winds, making it easier to install multiple units. Furthermore, if the generator and the blades are directly connected to the outer circumferential rotating part of the generator, the unit can be made thin and compact.

1 is an explanatory diagram of a structural example of a wind power generator unit according to the present invention; FIG. 1 is a comparative characteristic diagram of a coreless generator and a cored generator. FIG. 13 is an explanatory diagram of a four-coil connection pattern. FIG. 13 is an explanatory diagram of a connection pattern of five coils. FIG. 13 is a characteristic diagram of wind power generation by coil switching when four coils are used. FIG. 13 is an explanatory diagram of a circuit when four coils are used. 1 is a perspective view, with some parts omitted, illustrating the schematic structure of one embodiment of a hollow cylindrical coil used in a generator of the present invention. FIG. 1 is a plan view illustrating that the peripheral wall of the cylindrical coil is composed of three layers of cylindrical coil bodies in the radial direction of the cylindrical coil when viewed from the axial direction. FIG. 1 is a diagram illustrating an example of a cross-sectional structure of a wire that forms a single coil. 10 is a diagram showing an example of a wire arrangement in which, when winding the composite coil shown in FIG. 9, a thin wire independent of the composite coil wire is wound together with the composite coil wire. FIG. FIG. 13 is an explanatory diagram showing another embodiment of the coil switching pattern. FIG. 13 is an explanatory diagram showing yet another embodiment of the coil switching pattern. FIG. 13 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 12 . FIG. 13 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 12 . FIG. 13 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 12 . FIG. 13 is a characteristic diagram of a generator unit using coil switching in FIG. 12 . FIG. 13 is an explanatory diagram showing yet another embodiment of the coil switching pattern. FIG. 13 is an explanatory diagram showing yet another embodiment of the coil switching pattern. FIG. 13 is an explanatory diagram showing yet another embodiment of the coil switching pattern. FIG. 20 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 19. FIG. 20 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 19. FIG. 20 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 19. FIG. 20 is an explanatory diagram showing a change in the switching position in the embodiment of FIG. 19. FIG. 13 is an explanatory diagram showing yet another embodiment of a coil switching pattern. FIG. 13 is an explanatory diagram showing yet another embodiment of a coil switching pattern. FIG. 24 is a characteristic diagram showing the relationship between wind speed and rotation speed of each of the systems shown in FIGS. FIG. 24 is a characteristic diagram showing the relationship between wind speed and current for each of the systems shown in FIGS. FIG. 24 is a characteristic diagram showing the relationship between wind speed and system efficiency for each of the systems shown in FIGS. 19 to 23. 1A is a perspective view of the structure of an example of a frame used in a wind power generator unit of the present invention, (a) is a top view, (b) is a front view, and (d) is a side view. 1A and 1B are structural diagrams of an example of a blade used in a wind power generator unit of the present invention, in which (a) is a front view and (b) is an external view of one blade. 1A, 1B, and 1C are front and side views, respectively, of an example of a generator used in a wind power generator unit of the present invention; FIG. 1A and 1B are perspective views illustrating the external appearance of a wind power generator unit according to the present invention, in which FIG. 1A shows a state without a protective net, and FIG. FIG. 2 is a perspective view of an example of wind power generator units of the present invention connected side by side. FIG. 1 is a perspective view of an example in which wind power generator units according to the present invention are arranged side-by-side on a foundation such as a wall. 1A and 1B show examples of wind power generator units of the present invention connected vertically, in which FIG. 1A is a perspective view of three units stacked vertically, and FIG. 1B is a perspective view of six units connected in a 2×3 configuration. FIG. 1 is an explanatory diagram of an example of a construction method for fitting a wind power generator unit of the present invention between two steel frames (I or H steel). FIG. 1 is an explanatory diagram of an example of a construction method for fitting a wind power generator unit of the present invention between two steel frames (I or H steel). FIG. 4 is an explanatory diagram of another configuration example of the generator unit of the present invention. FIG. 4 is an explanatory diagram of another configuration example of the generator unit of the present invention. 1A and 1B are perspective views showing examples of wind power generator units of the present invention arranged on the rooftop of a building, in which FIG. 1A is an example of limited arrangement at a corner of the rooftop, and FIG. 1B is an example of connected arrangement around almost the entire perimeter. FIG. 1 is a perspective view of an example in which a wind power generator unit of the present invention is applied to a house. FIG. 1 is a perspective view of an example in which a wind power generator unit of the present invention is applied to a windbreak exterior wall of a solar power generation panel. FIG. 2 is an explanatory diagram of a case where the wind power generator unit of the present invention is installed on a coast. FIG. 2 is an explanatory diagram of a case where the wind power generator unit of the present invention is installed on a road. FIG. 2 is an explanatory diagram of a case where the wind power generator unit of the present invention is installed on a bridge.

(Example of device configuration of wind power generator unit)
FIG. 1 illustrates an example of a wind power generator unit 9 according to the present invention, with cross-sectional views (see also FIG. 32 for the external appearance).

This example has a thin, roughly rectangular box shape, and the housing 6 that forms its exterior is made up of a front section 61, a back section 62, a top section 64, a bottom section 65, and left and right side sections (omitted in this figure; see reference numeral 68 in FIG. 32), and the front section 61 and the back section 62 have large openings that form an air passage 63 that penetrates both sections 61-62. This air passage 63 has air collecting walls 66 formed on both the front section 61 and the back section 62 so that it narrows towards the center of the air passage (also called an air lens). The top section 64, bottom section 65, and left and right side sections may be plate-shaped, or may be just a frame (just a framework).

The generator 3 is located approximately in the center of the air passage 63, and the shaft 36 of the generator 3 is fixed to the housing 6 via a beam member (see reference numeral 67 in FIG. 32 in this drawing) that spans the opening outlets of the front part 61 and the rear part 62. Therefore, the shaft 36 does not move (does not rotate).

The casing 37 of the generator 3 is arranged with the shaft 36 as the central axis via the bearing 34, and the casing 37 rotates. Inside the generator 3, there are a cylindrical coil body 31, an outer yoke 32 and an inner yoke 33 arranged to sandwich the cylindrical coil body 31 with a gap, and a permanent magnet 35 joined to the cylindrical coil body 31 side of the outer yoke 32 and arranged with a gap between the cylindrical coil body 31, and further, a coil connection switching board 7 described later is provided so as to connect to the coil of the cylindrical coil body 31. The cylindrical coil body 31 is fixed to the shaft 36 and does not rotate, and the coil connection switching board 7 connected to the cylindrical coil body 31 is also non-rotating, but the outer yoke 32 and the inner yoke 33 are integrated with the casing 37 (particularly in this example, the outer yoke 32 doubles as the casing 37), and therefore rotate. The permanent magnet 35 is also joined to the outer yoke 32 and therefore rotates.

The cylindrical coil body 31 is fixed inside in a cantilevered state to keep it stationary (non-rotating) against the rotation of the yoke. A coil reinforcing layer (see, for example, JP 2021-97546 A) is formed on one or both sides of the cylindrical coil body 31 so that the cylindrical coil body 31 can respond to circular twisting or positional deviation due to the rotational motion or magnetic force of the rotor, and a coil reinforcing ring (see, for example, JP 2021-97564 A) is further fitted to the open end side of the cylindrical coil body 31. In addition, the coil connection switching board 7 is connected to the cylindrical coil body 31 and is therefore non-rotating, and wiring and switches (one or more semiconductor elements and/or relays) of the switching circuit are mounted on it. Although not shown, it is also effective to directly and/or indirectly cool the internal heat generation with a refrigerant.

The multiple blades 1 are fixed to the casing 37 (which also serves as the outer yoke 32 in this example), so the blades 1 and the generator 3 rotate together. In this example, the front portion 61 and the rear portion 62 are symmetrical, and the blades 1 are made symmetrical so as to accommodate winds flowing in from both the front portion 61 and the rear portion 62. The blades 1 can be fixed to the casing 37 (= the outer yoke 32 in this example) by screws or welding or other means, but should be fixed in a strong manner that can withstand centrifugal force.

Furthermore, the front portion 61 and the rear portion 62 may be covered with a protective net (not shown in the figure, see reference numeral 69 in FIG. 32). Each surface may be made of a skeleton of plate material.
In addition, it is advisable to use an oil seal in order to prevent foreign matter from entering the inside of the generator 3, such as the bearing 34.

The generator 3 may further be equipped with a speed increaser and brakes, which may be stored in the space inside the inner yoke 33 of the coreless generator 3. A speed increaser uses gears to increase the number of rotations and speed up the rotation, but a speed increaser is not necessary for generators of around 1 kW, and is not actually necessary for the coil-to-coil connection switching type coreless generator that is the subject of this invention. The brake device is responsible for suppressing or stopping the rotation in strong winds, during inspection, etc. However, the brake device is not essential.

The transmitted rotation is converted to electricity by the coreless generator 3. The coreless generator 3 will be described in a separate section, but the cylindrical coil body 31 in the coreless generator 3 used in this example is formed in a cylindrical shape. The generated electricity is distributed to the user via an output cable (not shown), through a storage battery (e.g., a lead storage battery) (not shown), or directly. Note that the present invention also includes cases where the voltage is boosted via a transformer, but as will be described later, if a coil-to-coil connection switching board 7 is used, the coil-to-coil connection switching itself increases the voltage, so there is no need to use a separate complex boost circuit (DC-DC converter).

Furthermore, although not shown in the figure, the generator unit is equipped with a communication device (with a transceiver, antenna, and sensor; see reference number 11 in Figure 34) and a wind direction and speed meter for monitoring purposes, and the monitoring communication device is used to monitor the wind direction, wind speed, and the status of the storage battery at a monitoring center (not shown).

(Characteristics of coreless generators)
Wind power generation converts wind energy into mechanical energy using a windmill, which then converts the mechanical energy into electrical energy using a generator. The maximum conversion efficiency of a windmill is 59.3% (about 60%: Betz's theorem), but currently, the conversion efficiency is about 40% for an ideal windmill and about 30% for a normal windmill. Given the above, the power generation efficiency of a wind power generation system is about 30% to 35% at best, assuming that the generator efficiency is 80% to 90%. Generally, a 1kW generator is designed with a blade diameter of 2m, an area of 3.14m2, and an efficiency of 31.8%. The peripheral speed ratio of the blade type (ratio of wind speed to blade tip speed) is generally chosen to be 6 (high conversion efficiency), and the blade tip speed at rated time (wind speed of 12m/sec) is 259.2km/h and the rotation speed is 688rpm.

Wind energy is proportional to the cube of the wind speed. Wind pressure is proportional to the square of the wind speed, and wind energy is wind speed x pressure = the cube of the wind speed. Therefore, when the wind speed is small, the energy is very small, and conversely, when the wind speed increases, the energy increases rapidly.

At present, the operating range of a wind turbine is generally below 2.5 m/s, where the energy required to operate the control circuit is greater than the energy that can be generated, and above 15 m/s, the output is too high and there is a high possibility of damaging the generator and control circuit. As can be seen from the above, the biggest challenge for a wind turbine system is to be able to efficiently utilize a wide range of winds, from light breezes to strong winds.

Generally, permanent magnet synchronous generators are used in small wind turbines. Although cored types of permanent magnet generators are widely used, the inventors' research has shown that coreless types are more suitable.

As shown in the graph in Figure 2, in the case of generators with the same induced voltage constant, a coreless generator can obtain a higher voltage than a cored generator (in this application, this refers to a generator with an iron core, not using a cylindrical coil. Therefore, slotless types are excluded because they use a cylindrical coil), and as a result, the output current can be reduced when obtaining the same output. The reason for this is that the inductance of a coreless generator (slotless generators as well) is small, and the voltage drop 2πfLI due to inductance is small. And because it is a type using a cylindrical coil (a type without an iron core inside the cylindrical coil. The same applies below), it is cogging-free, and therefore the blades can rotate easily even in a light breeze. Even if there are conventional wind power generators that claim to be compatible with light winds, if the essential generator is not a type using a cylindrical coil, there will be cogging and it will not rotate in a light breeze, so in reality it is difficult to achieve the effect of being compatible with light winds. In this way, the present invention is cogging-free because it is a type using a cylindrical coil, and therefore the blades of the wind power generator will rotate even in a light breeze. In addition, because it uses a cylindrical coil, the inductance is small, and therefore the voltage drop is small even when rotating at high speed, resulting in more power generation. This contributes to making wind turbines smaller and lighter.

Furthermore, the coreless type can be easily used in conjunction with the coil connection switching principle, which will be described later in a separate section. Using this coil connection switching system makes it possible to control the generated voltage, improving power generation efficiency and achieving energy savings. This system also makes it possible to charge over a wide range of conditions, from light breezes to strong winds, improving charging efficiency.

The coils of conventional coreless generators are usually flat to maintain their shape and make them compact. In contrast, in this invention the coils are made cylindrical, and therefore the yoke and casing are also cylindrical, but the inventors have devised a structure similar to that of a wheel-in motor by fixing the blades to the yoke and casing. In conventional wind turbines, the blades and generator are connected in series by a power transmission shaft, which results in a wide generator unit, but the structure proposed in this invention compresses the width, resulting in a thin coreless generator unit.

(Principle of switching between coil connections for multiple coils)
This invention is characterized by not simply switching between two types of coil units, serial and parallel, but by using serial and parallel together to provide three or more variations in the switching pattern, that is, by performing multi-stage switching. This allows multi-stage switching of three or more stages according to wind force, making it possible to handle anything from light breezes to strong winds.

The coil section of a generator is made up of multiple phases, typically three phases: U, V, and W. In this invention, three or more coil units are used for each phase. The coil units can be connected all in series, all in parallel, or a mixture of series and parallel (series-parallel), making it possible to switch between three or more stages. A typical example is the use of four coil units for each phase as shown in Figure 3 (in this example, each coil unit uses one coil, so there are four coils in total), and a pattern for five coil units (in this example, each coil unit uses one coil, so there are five coils in total) is shown in Figure 4.

As can be seen from Figs. 3 and 4, the more the number of coils is increased, the more variations in the switching patterns of the coil connections are available, and the more detailed the response to wind speed can be. It is not necessary to use all patterns. For example, as explained in Fig. 5, if four coils are used, three patterns are acceptable: all in series (4S = 1P-4S. 1 parallel), all in parallel (4P = 4P-1S. 4 parallel), and two parallels in series (2P-2S. 2 parallel). In that case, all in series corresponds to high wind speeds, all in parallel corresponds to low wind speeds, and two parallels in series corresponds to medium speeds. In the case of a system capable of generating power from an output voltage of 30V, if there is no coil switching (conventional type), power can be generated from a wind speed of 3m, but if the three-stage switching of this example is adopted, power can be generated from a wind speed of 0.75m. This is illustrated in Fig. 5. Fig. 5 is a graph of four coils in three stages. Assuming three-stage switching, there are four coils, switching between 4S (1 parallel), 2P-2S (2 parallel), and 4P (4 parallel). In the table, "low speed" uses 4S (1 parallel) at the lower wind speed, "medium speed" switches to 2 parallel, and "high speed" switches to 4 parallel (automatic switching). Table 1 summarizes the relationship between wind speed, rotation speed, and output voltage in the case shown in Figure 5. Switching between coil units (hereinafter, switching between coil units will be referred to as coil switching) can be automatically switched depending on the wind speed.

Next, the coil connection switching board 7 will be explained using an example of four coils in Fig. 6. Fig. 6 uses a relay in the switch circuit, but of course it is more practical to use a semiconductor circuit or a combination of a semiconductor element and a relay.

The cylindrical coil body 31 (also called the stator coil) according to this embodiment is a three-phase, 12-pole structure using four coils (12 in total) per phase. In such a coil body, switch circuit units 72 (72U1, 72U2, 72U3, 72V1, 72V2, 72V3, 72W1, 72W2, 72W3) are provided between the coils constituting each phase (first coil U1, second coil U2, third coil U3, fourth coil U4, first coil V1, second coil V2, third coil V3, fourth coil V4, first coil W1, second coil W2, third coil W3, fourth coil W4). Reference numeral 71 denotes a control unit. The control unit 71 and the switch circuit 72 are mounted on the coil-to-coil connection switching board 7 as semiconductor circuits, so that there are connection wires (not shown) between each coil and the coil-to-coil connection switching board 7.

The switch circuit unit 72 is configured such that the switch circuit units 72U1, 72U3, 72V1, 72V3, 72W1, and 72W3 are configured with two changeover switches (first switch A, second switch B) with one input port and two output ports arranged in parallel. The first coils U1, V1, and W1 are connected to the input ports of the first switch A, respectively, and the first bypass line is connected to the input port of the second switch B. The output ports of the first switch A are connected to the second coils U2, V2, and W2 on the a-port side, and the second bypass line is connected to the b-port side. In addition, the output port of the second switch B is open (unconnected) on the a-port side, and the branch lines from the second coils U2, V2, and W2 are connected to the b-port side.

On the other hand, the switch circuits 72U2, 72V2, and 72W2 are configured so that the number of input ports and the number of output ports for the second switch B are reversed to those for the first switch A. With this configuration, in each of the U-phase, V-phase, and W-phase, the first coil U1 to the fourth coil U4, the first coil V1 to the fourth coil V4, and the first coil W1 to the fourth coil W4 are each connected in series by setting the first switch A and the second switch B to port a for the switch circuits 72U1 to 72W3 (this state is referred to as 1 parallel).

In addition, when the first switch A and the second switch B of the circuit parts 72U2, 72V2, and 72W2 are set to the b port from the 1-parallel state, for example, in the U phase, the first coil U1 and the second coil U2 are connected in series, and the third coil U3 and the fourth coil U4 are connected in series, and the set of the first coil U1 and the second coil U2 and the set of the third coil U3 and the fourth coil U4 are connected in parallel. Note that the coils are connected in the same way in the V phase and the W phase (this state is called 2-parallel).

Furthermore, in each of the U-phase, V-phase, and W-phase, when the first switch A and the second switch B are set to port b for the circuit sections 72U1 to 72W3, the first coil U1 to the fourth coil U4, the first coil V1 to the fourth coil V4, and the first coil W1 to the fourth coil W4 are connected in parallel (this state is called 4-parallel). However, there is no limit to the number of coils and the number of stages, as long as there are three or more coils and three or more switching stages.

(How to wind a coil)
7 to 10 show an example in which the cylindrical coil body 31 is braided with Litz wire, but the manufacturing method is not limited to this.

The coil body used in the embodiment of the present invention is made by winding wire material, not by etching a copper plate. However, it may be made of multiple phases, each of which is formed by multiple coil units, and may be a method proposed by the inventor in Patent No. 6989204 or Patent No. 6948748, with the aim of maintaining the shape while suppressing the thickness of the coil body. Of course, the coil body is not limited to these winding methods, and if the above switching idea is followed, a method using copper plate instead of wire material would also fall within the scope of the present invention.

The hollow cylindrical coil body 31 of this embodiment is formed from a plurality of coil units 312. Each coil unit 312 is wound a plurality of times, for example 10 turns. The peripheral wall 31a of the cylindrical coil body 31 is formed by continuously arranging the plurality of coil units 312 in the circumferential direction of the cylindrical coil body 31. Note that a coil unit refers to one coil, and one or more of these form a coil unit, which is further bundled together to form a cylindrical coil body.

As shown in FIG. 8, the peripheral wall 31a is composed of an inner cylindrical coil body 313, an intermediate cylindrical coil body 314 arranged outside the inner cylindrical coil body 313 in the radial direction of the cylindrical coil body 31, and an outer cylindrical coil body 315 arranged outside the intermediate cylindrical coil body 314 in the radial direction of the cylindrical coil body 311. The inner cylindrical coil body 313, the intermediate cylindrical coil body 314, and the outer cylindrical coil body 315 are each formed by continuously arranging multiple coil units 312 in the circumferential direction of the cylindrical coil body 31. The reference symbol 311 is the central axis (virtual) of the cylindrical coil body 31. The cylindrical coil bodies 313, 314, and 315 may each form a U, V, and W phase, or may be woven in a manner that mixes them together.

The wire 316 forming the coil unit 312 is a conductive wire whose periphery is insulated. An example is shown in FIG. 9. The wire 316 shown in FIG. 9 uses a so-called Litz wire, and multiple copper thin wires 317 covered with an enamel layer 318 on the outer periphery are bundled together, and this is covered with a fibrous material 319 such as glass fiber. The coil unit 312 before being continuously arranged in the circumferential direction of the cylindrical coil body 31 so as to form the cylindrical peripheral wall 31a of the hollow cylindrical coil body 31 is a substantially flat coil body. The coil winding method described below is, for example, as described in the examples of the above-mentioned Patent No. 6989204 and Patent No. 6948748. Each phase is formed by this winding method, and in each of the inner cylindrical coil body 313, the intermediate cylindrical coil body 314, and the outer cylindrical coil body 315, a wire 316 is drawn out from the cylinder of the cylindrical coil body 31 to provide a coil connection changeover switch for switching the coil connections. This switch is fixed to the coil connection changeover board 7 in FIG. 1 by using a semiconductor circuit.

The fibrous material 319 of the wire 316 described using FIG. 9 is made into a material that melts when heated, such as glass fiber, and the flat coil bodies that become the inner cylindrical coil body 313, the intermediate cylindrical coil body 314, and the outer cylindrical coil body 315 are prepared as described above using a plurality of coil units 312, and further, the intermediate cylindrical coil body 314 is arranged radially outward of the inner cylindrical coil body 313, and the outer cylindrical coil body 315 is arranged radially outward of the intermediate cylindrical coil body 314, with the inner cylindrical coil body 313, the intermediate cylindrical coil body 314, and the outer cylindrical coil body 315 being arranged so as to be shifted from each other in the circumferential direction of the cylindrical coil body 31 by a predetermined displacement amount, and then heated to thermally fuse the fibrous materials together to form the hollow cylindrical coil body 31 of this embodiment, in which the peripheral wall 31a is formed to a thickness equivalent to two layers of the coil units 312.

By the way, as for the generator-compatible embodiment shown in Figs. 12 to 15 and Figs. 24 and 25, the inventor proposes winding one thin wire 320 without a switch together with the wire 316 described above (see Fig. 10). The constituent wires in Fig. 9 are substantially of the same standard in thickness and characteristics, but one of the constituent wires (or a conductor slightly thicker than the thin wire and thinner than the outer diameter) is wound together. However, unlike the wire 316, this thin wire 320 does not have a switch between the thin wires 320, and its role will be described later. There is only one thin wire, and it can be handled structurally as a thickness error range. For example, even if the number of turns is 10 turns each and the thin wire 320 is wound together with the wire 316, the number of turns can be changed between the wire 316 and the thin wire 320. In short, if the thin wire 320, which is used only in light winds, is wound together with the wire 316 when it is made, the manufacturing process is convenient. In this section, an example of using a normal Litz wire in combination with one thin wire has been shown, but the use of one thin wire is not limited to this (examples of this will be described in the examples of Figures 24 and 25).

Due to the above-mentioned structure, a plurality of coil units 312 are continuously arranged in the circumferential direction of the cylindrical coil body 31 to form the inner cylindrical coil body 313, the intermediate cylindrical coil body 314, and the outer cylindrical coil body 315. Furthermore, the intermediate cylindrical coil body 314 is arranged radially outward of the inner cylindrical coil body 313, and the outer cylindrical coil body 315 is arranged radially outward of the intermediate cylindrical coil body 314. When the cylindrical coil body 31 is formed, the amount by which the coil units 312 bend in the radial direction of the cylindrical coil body 31 does not substantially exceed the thickness size of the coil units 312.

Therefore, it is possible to suppress the stress on the wire 316 that forms the coil unit 312. In addition, the radial thickness of the peripheral wall 31a of the cylindrical coil body 31 is equivalent to twice the thickness size of the coil unit 312, and does not exceed at least three times the thickness size.

In the cylindrical coil body 31 of this embodiment, the multiple coil units 312 constituting the peripheral wall 31a are structured so that there is no portion where the wire 316 bends radially outward from the winding axis while the wire 316 is being wound around the winding axis. Therefore, compared to the case where a coil unit having a hairpin-shaped bulge radially outward from the winding axis is used, an increase in electrical resistance can be suppressed from the perspective of the coil path. And, as described above, the degree of bending in the radial direction of the cylindrical coil body 31 can be reduced, so the mechanical stress on the wire 316 can also be reduced.

(Further embodiment 1 of coil switching)
Another coil switching method is explained in Fig. 11. In this example, six coils are used for each phase. When six coils are used, the following 12 patterns can be selected, including all in series, but in this example, only three of them are used.

The 12 patterns are as follows (P is parallel, S is series): All in parallel (6P), 5P+1S, 4P+2P, 4P+2S, 3P+3P, 3P+2P+1S, 3P+3S, 2P+2P +2P, 2P+2P+2S, 2P+4S, 2P+3S (one unused), 6S (all in series).

In the example of Figure 11, three patterns are used: all in series (6S. If each coil is 1V, 1Ω, it is 6Ω, 6V), 2P+2P+2P pattern (same as 1.5Ω, 3V pattern), and 3P+3P (same as 0.66Ω, 2V). The all in parallel pattern is also not used. In this way, the width of the three maximum rotation speeds is equalized as shown in the graph of Figure 11 (note that k on the vertical axis of the figure is a coefficient. For example, if k is 100, 6k is 600 rotations). In this way, since there are not 12 patterns of fine switching, the number of switches can be reduced as shown on the right side of Figure 11, and since the difference in rotation speed is uniform, control management is easier. Not only can the number of contacts (switches) be reduced, which reduces costs, but if the maximum switching rotation speeds are set at equal intervals of 1k, 2k, and 3k and 3k is set as the upper limit for use, there will be no large difference up to 6k, which will prevent damage to the machine (this prevents the load on the machine from a large sudden change in the maximum rotation speed).

Similarly, doubling the number of coils for each phase from six to twelve will produce a similar thinning effect (see Figure 18). Although the number of coils increases with 12 coils, the switches (semiconductors) do not require the full number of coils, and a large torque can be obtained when 12 coils are connected in series. In the example of Figure 18, 6P2S and 12P are not used (6P2S and 12P are not possible in the first place), so the number of rotations for the four-stage switching is evenly distributed between 0-1, 1-2, 2-3, and 3-4. When using 12 coils, the number of rotations can be selected from 12k, 6k, 4k, 3k, 2k, and 1k (k is a coefficient), but if it is less than 4k, the intervals are all evenly distributed at 1k, meaning that switching between the four options of 4k, 3k, 2k, and 1k will prevent mechanical damage due to switching shock, just like the 6-coil example above. Although the gap between 6k and 4k is slightly wider, it is much narrower than the gap between 12k and 4k, so even if 6k is selected, it is effective in suppressing mechanical damage caused by shock, and as a result, 12k can be left unused and 6k, 4k, 3k, 2k, and 1k can be selected. Of course, the number of switches will be drastically reduced compared to the number of coils used.

(Further embodiment 2 of coil switching)
12 to 15 show the circuit of FIG. 11 (6 coils switched out) (this 6 coil section is referred to as coil group A in this example only), and furthermore, by connecting or disconnecting a section formed by a single thin wire (referred to as coil group B in this example only) in series, more suitable operation is achieved from light breezes to strong winds. Incidentally, if coil group A corresponds to wire 316 in FIG. 10 and has a normal coil thickness, coil group B corresponds to thin wire 320 in FIG. 10 (for convenience of drawing, coil groups A and B are shown to have the same thickness in FIG. 12 to FIG. 15, but in reality they are different as shown in FIG. 10 (thin wire 320 may be relatively thinner). Incidentally, although multiple thin wires 320 are seen in FIG. 10, this is merely an expression of the coil being wound with many turns, and the actual thing is a single wire.

The winding method in Figure 10 mentioned above is effective for connection, and the thin wire 320 in Figure 10 will carry this coil group B. In other words, the coil group A (made from wire 316) has a coil switch as shown in Figure 11, but the thin wire 320 has only one switch along the way. Whether or not to use coil group B in the thin wire 320 section is determined by switching switch C. In the example in this figure, each coil in coil group A is wound with 10 turns, and there are 6 coils, so that is 60 turns. The thin wire of coil group B is also wound with 60 turns, and if the wire 316 of coil group A and the thin wire 320 of coil group B have the same number of turns, it is more efficient to wind them together as in Figure 10.

In the connection pattern of Figure 12, coil group A is all connected in series and is further connected to coil group B. This coil group B section is made of thin wire so the resistance is high, but it is effective in light breezes (for example, wind speeds of 4 m/s or less as a guideline). When using this thin wire section (coil group B), the resistance increases, but since this is in an extremely light breeze of 4 m/s, and the current that can be extracted is small, the problem of increased resistance does not need to be a concern. Instead, this mode places emphasis on firmly catching the small amount of wind in extremely light breeze sections (above 0 and below 4 m/s) to generate electricity and charge.

13 to 15, the connection between coil group A and coil group B is cut off, and coil group B is not used. In the connection pattern of Fig. 13, coil group A is all in series, in the connection pattern of Fig. 14, coil group A uses 2P3S, and in Fig. 15, coil group A uses 2S3P.
The above is the same for the U phase, V phase, and W phase, which are connected by a common line.

Figure 16 shows the wind power generation characteristics when this embodiment is used. Generally, as the wind speed increases from 0 to a strong wind, the generated voltage rises. However, in this example, when the generated voltage reaches a certain level, the generated voltage drops due to coil connection switching. This characteristic changes sequentially from pattern (1), to (2), to (3), to (4). In other words, this embodiment is characterized by using the thin wire connection of pattern (1) when there is a light breeze, and the voltage drops each time the coil is switched, as shown in the figure. Also, as shown in Figure 16, even with a light breeze of 8 m/s or less, the generated voltage can be secured at 8 V or more with connection pattern (1), compared to when there is no coil connection switching (the relationship between wind speed and generated voltage is proportional). In other words, the increase in voltage makes it easier to extract output and easier to store electricity, making it an important energy acquisition method, especially when using lead-acid batteries.

In fact, the lead-acid battery used in this example usually has a charging voltage of 8V to 16V. If it is less than 8V, it cannot receive power, and if it is more than 16V, the battery will break. Therefore, the coil is switched so that it can handle strong winds at 16V or less. However, on the other hand, the time period when the wind is light is the most common in daily life, and the time when the wind blows at 4m/s or more is generally few throughout the year. Therefore, it is a waste as a natural energy source to be unable to use it at a light breeze (ultra-light breeze) of 4m/s or less. For example, in Japan, most of the day is in this ultra-light breeze (extremely light breeze) state. There are many situations where the wind speed is less than 2.5m/s. The second important feature of this embodiment is that it is possible to catch the energy source even with an ultra-light breeze by adopting pattern (1). In addition, in order to capture the wind without missing even this ultra-light breeze and convert it into electricity, the generator structure, especially the blades, is made small and lightweight, and the shaft itself is made lighter so that the mechanical resistance of the power transmission shaft can be reduced and it rotates smoothly, and bearings are also arranged. To make the wind generator small and lightweight, a coreless type without an iron core is exactly the best.

In this example, the pattern for connecting coil group A and coil group B is limited to series, but as a modified example, coil group A and coil group B can be connected in parallel as shown in Figure 17. In the example in this figure, each coil in coil group A is wound with 10 turns, and since there are 6 coils, there are 60 turns, and the thin wire of coil group B is also 60 turns, but the number of turns of coil group B can be increased (for example, to 200 turns). In order to enable parallel connection, switch D is added in this figure, and when the connection between coil group A and coil group B by switch C is cut, switch D is connected to put coil group A and coil group B in a parallel relationship. Since the coil group B section is made of thin wire, the resistance is high, and using this thin wire section (coil group B) increases the resistance, but since the wind is extremely light, such as 4 m/s, and the current that can be extracted is small, there is no need to worry about the problem of increased resistance. Therefore, this example is also suitable for very light winds. In this way, in addition to multiple coil switching, using a switchless coil made of wire thinner than the coil wire in question is suitable for very light winds. Incidentally, in this embodiment, the switches between the coils (both the switches within the range of coil group A and switch C) may be mechanical relay switches rather than semiconductor switches when the wind speed is zero or very light. In other words, the semiconductor switches and the mechanical relay switches are used together (selective switching). This is intended to prevent battery consumption due to driving the semiconductor switches when there is essentially no wind. If a current is generated with an increase in wind speed, the current can be detected, so it is sufficient to switch from the mechanical relay switch to the semiconductor switch. In other words, the mechanical relay switch turns OFF when a generated voltage is generated.

(Further embodiment 3 of coil switching)
Another example of switch arrangement when 12 coils are used for each phase will be described with reference to Fig. 18. As shown in the figure, 16 switches are used.

As the graph in the figure shows, maximum RPM 1 corresponds to 12S, 2 corresponds to 2P6S, 3 corresponds to 3P4S, 4 corresponds to 4P3S, and 6 corresponds to 6P2S. To achieve 12S, connect switches f, g, h, i, and j in the figure and turn off the other switches. To achieve 2P6S, connect switches c, f, g, i, j, k, and n and turn off the other switches. For 3P4S, connect b, d, f, h, k, m, and o and turn off the others. For 4P3S, connect a, c, e, g, i, k, l, n, and p and turn off the others. In the example in this figure, 2S6P and 12P are not possible, but depending on the needs of the generator, there is no need to use these switch selections.

(Further embodiment 4 of coil switching)
19 to 23 show an embodiment in which 24 coils are used for each phase (if a coil having the same material, length, and resistance value is considered to be one unit of coil, then 24 unit of coils are used for each phase. This is a common concept throughout the present description).

This example shows five-stage switching from stage 1 to stage 5. Figure 19 shows the first stage (hereinafter referred to as the first system). Each coil is 1V, resulting in 20V. Figure 20 (hereinafter referred to as the second system) shows the second stage at 16V, Figure 21 (hereinafter referred to as the third system) shows three stages at 12V, Figure 22 (hereinafter referred to as the fourth system) shows four stages at 8V, and Figure 23 shows five stages (hereinafter referred to as the fifth system) at 4V.

Since the generated voltage per rotation speed is large (the induced voltage constant is large), the more coils there are, the more electricity can be generated even at low rotation speeds. In other words, electricity can be generated even in extremely light breezes.

In this embodiment, as can be seen in the coil connections at the left end of each figure, four coils in series are provided in parallel to the section of four coils in series (this additional parallel portion is referred to as the auxiliary coil in this application). With this arrangement, the number of switches does not need to be increased even if the number of coils is increased. The timing and effects of the five-stage switching using the first to fifth systems will be described later in a separate section (see the section on timing and characteristics of coil connection switching).

(Further embodiment 5 of coil switching)
Figures 24 and 25 show another embodiment using 24 coils. In this example, two types of coils are used, one thick (usually used, referred to as thick coil in this specification) and one thin (referred to as thin coil in this specification) although they are made of the same material and have the same length. The difference in thickness can be adjusted by the number of thin wires used, for example, if Litz wire is used.
In the example of Fig. 24, 14 thin coils are connected in series, and there are two sets of five thick coils connected in series. Switch A is provided between the thick coils and the thin coils, and three switches B are provided in the two sets of thick coils as shown in the figure, and switch C is provided on the line that does not pass through the thin switches. In this example, 14 bundles of Litz wire are connected in series for 14 coils, and when the wind speed is less than the set speed (very light wind), switch C is closed and switch A is connected, connecting the thin coils in series, and when the wind speed is above the set speed, switch A is cut off and switch C is turned on, putting the coils in an unused state. In other words, the thin coils for very light winds are not used above the specified wind speed. On the other hand, in this example, two units of 40 bundles of Litz wire for five coils are prepared for the thick coils, allowing for switching between series, parallel, and series-parallel between the units, and if the wind speed is not very light, multiple coil switching is possible even when the thin coils are not used. When the wind speed is less than a certain level (very light wind), the thin coils are connected in series and the thick coil units are also connected in series, meaning that all 24 coils are connected in series. In this example, waterproof relays are used for switches A and C, and a semiconductor element is used for switch B.

Figure 25 also uses a total of 24 coils, combining thick and thin coils, but it differs in that it has 12 thin coils and 2 units of 6 thick coils, for a total of 12 coils. Switches A to C are the same as in Figure 25, and the warning lamp 70 lights up depending on the thin coil usage status, for example when the wind speed is below a certain level or when switch A is shut off.

In this example, just like the example in Figure 24, the total number of thin and thick coils is 24, so if each coil is 1V, then 24 coils in series will generate 24V. If the thin coils are disconnected (not used) and only the thick coils are connected in full series, 12V will be generated, and if the thin coils are not used and two units of thick coils are connected in parallel, 6V will be generated. In this example, the thick coils are made of Litz wire consisting of 40 bundles of thin wire with a fine wire diameter of 0.15 mm, and the thin coils are made of Litz wire consisting of 14 bundles of thin wire of the same diameter.

The use of both thin and thick coils is not limited to the above example; thin coils can be used only when there is a very light breeze, and otherwise multiple stages can be switched by switching the connections within the thick coil group.

(Timing and characteristics of coil connection switching)
The effect of the present invention will be verified by taking the five-stage switching shown in Figures 19 to 23 as an example. In this verification experiment, nine blades with a blade angle of 20° were installed on a square frame with a front side of 1.5 m and a width of 30 cm, and 12 coils were used for each phase (since the number of coils is 24 in the illustrations of Figures 19 to 23, two of these coils combined into one became the coil body used in this experiment. Therefore, while there are four auxiliary coils for each phase in Figures 19 to 23, there are two coils for each phase in this verification. Therefore, the first system has 10 coils in series, the second system has 8 coils in series, the third system has 6 coils in series, the fourth system has 4 coils in series, and the fifth system has 2 coils in series, allowing five-stage switching.

The results of the charging test using a 12V lead battery for each system are as shown in the table below.

When the above data is graphed, the relationship between wind speed and rotation speed will be as shown in Figure 26, the relationship between wind speed and current will be as shown in Figure 27, and the relationship between wind speed and system efficiency (= power generation efficiency) will be as shown in Figure 28. The reason why the 5th system does not appear in Figures 27 and 28 is because the verification was conducted in a light breeze, and it has been omitted simply because it does not appear in the graphs unless the wind speed exceeds 10 m/s.

In FIG. 28, the system automatically switches to the stage system with the greater system efficiency at each wind speed. Therefore, in the wind speed range where the first system exceeds the second system, the first system is applied, and in the wind speed range where the second system exceeds the third system, the second system is applied, and then the third system and the fourth system are applied in sequence. In this way, the switching method of the present invention maximizes the blade's capabilities. Note that automatic switching is more practical than manual switching, but manual switching is also applicable to the present invention. In addition, it is recommended that the switching has a hysteresis of about ±0.5 m/s to prevent chattering. In other words, to prevent chattering, it is recommended that the system be switched at a wind speed that is slightly higher (for example, +5 m/s) in the direction of increasing wind speed, and that the system be switched at a wind speed that is slightly lower (for example, -5 m/s) in the direction of decreasing wind speed.

The inventors examined each parameter and discovered that system efficiency changes depending on the coil connection status. They then invented that it is best to set the switching timing of the coil switching device so that it maximizes the system efficiency of the generator. The system efficiency of a wind turbine generator can be calculated using the formula below, and the coil switching device introduced in this invention allows for switching between three or more stages with different system efficiencies, and this system efficiency switching makes it possible to always provide the best system efficiency.

The system efficiency is given by:

The procedure for switching based on the current value, for example, is to obtain data on system efficiency in response to changes in wind speed for each system, and then it is possible to know the current value at which each system's efficiency is at its highest, and then detect the current value that maximizes system efficiency and switch based on the current value. Furthermore, to prevent chattering, it is desirable to set an optimal hysteresis for the current value to be switched. The current value is set on the output side of the generator, that is, between the generator and the storage battery.

(Example of wind power generation unit assembly)
Figure 29 shows an example of the structure of the frame of a wind power generation unit. (a) is a perspective view, (b) is a top view, (c) is a front view, and (d) is a side view. In this example, the frame 81 is configured so that the appearance is a thin rectangular parallelepiped, and triangular plates 80 are provided at the four corners of the front and back to reinforce the frame, and beams 82 are provided vertically and horizontally on the front and back, with the generator shaft (described later) passing through the center where the beams cross. In this example, no wind collecting section is provided to simplify the structure. Therefore, in this example, there is no wind collecting section (wind lens), and each surface of the unit is in the form of a framework rather than a plate.

Figure 30 shows the blade section, (a) is a front view, and (b) is an enlarged view of one blade. The center is the position of the shaft 36, reference number 110 is an imaginary line of the rotation range of the blade 1, reference number 111 is a reinforcing rib, reference numbers 112 and 113 are wind direction guidance parts and reinforcing ribs where the end of the blade 1 is bent, and reference number 114 is an attachment part to the generator unit. In this example, there are nine blades 1, but the size, shape, and number are not limited to this.

Figure 31 shows the generator part, (a) is a front view, (b) is a side view, and (c) is a perspective view. The rest of the assembly structure is as shown in Figure 1.

(Installation example of the wind power generator unit of the present invention)
As explained above, the present invention not only reduces the size and weight of the wind power generator unit, but also makes it thinner by integrating the blades and the generator into a wheel-in type. Moreover, since it can store electricity even in the lightest winds, it can be installed in a much wider range of locations.

Figure 32 shows the appearance of the wind power generator unit 9 manufactured for each of the following installation examples using the structure of Figure 1, (a) is a perspective view without a protective net, and (b) is a perspective view with a protective net. Each reference numeral follows the explanation of Figure 1 and is therefore omitted. Reference numeral 67, which is not shown in Figure 1, is a beam for fixing the shaft of the generator 3 to the housing 6, and reference numeral 69 is a protective net. As shown in this figure, the wind power generator unit of the present invention is a thin rectangular parallelepiped (although the corners are rounded). In addition, each wind power generator unit is led to a storage battery (e.g., a lead-acid battery) that stores the generated electricity. Note that the protective net 69 is not shown in each of the following installation examples, but this is to avoid complicating the drawings, and in all cases the protective net 69 is attached to the front and back parts.

(1) Example of horizontal arrangement Figure 33 shows an example of three wind power generator units 9 arranged horizontally. Of course, there is no restriction on the number of units to be installed. The housing may be just a frame, or the front and back parts may be flat or curved plates, and the top, bottom, and both sides may be just a frame without plates. It is preferable to form a wind lens (wind collecting part 66, see Figures 1 and 32) on almost the entire front and back except for the wind tunnel. In this example, as shown in Figure 1, it is designed to receive wind from both the front and back. Furthermore, if each of the constituent plates is made into a skeleton, it becomes possible to see the scenery ahead without any obstruction. This horizontal arrangement type can be used as a windbreak generator by placing it on an exterior wall or replacing a part of the exterior wall. Note that the height of each wind power generator unit is 1 to 2 m, and if the width is less than half the height, it can be used to replace walls, fences, hedges, and barriers (for example, railway fences), and the like, and visibility can be secured when looking into the distance. The dimensions of each wind power generator unit 9 are 150 cm in length and width, and 15 cm in width. These dimensions are also common to the wind power generator units 9 used in the following installation examples.

(2) Example of Arrangement on a Base Figure 34 shows an example of arranging the wind power generator units 9 side by side on a base 10 on which the units are installed. Of course, the number of wind power generator units 9 may be increased. The height of the base 10 is, for example, 10 cm, and the thickness is approximately the same as that of the wind power generator units 9. Reference numeral 11 denotes a wireless LAN transceiver attached to each wind power generator unit 9 for communicating the operating status of each unit. Data obtained from each wireless LAN device 11 can be monitored in the installation area together with the status of the storage batteries. In this example, as in the other examples, the blades 1 are symmetrical with respect to wind from both sides, and of course the structure allows wind to flow in from both the front and back.

(3) Examples of vertical stacking Figure 35 shows an example of vertical stacking, where (a) shows three stacked vertically, and (b) shows six stacked vertically in a 2 x 3 pattern. In this way, it is possible to stack two or more layers. Reference numeral 12 denotes a wire with a support function to prevent the stack from falling over, but of course the support means for preventing the stack from falling over is not limited.

(4) Installation example of a thin generator unit fitted between two rails Figure 36 shows an example of a thin generator unit, and Figure 37 shows an example of fitting it between rails. In this example, the width of the unit is 40 cm, the front is roughly rectangular with one side measuring 2 m, and a coreless generator 85 and blades 86 are arranged so that they fit into a hole 92 by a beam 94. The central diameter of the hole 92 is 1.36 m, and a wind lens is formed by a wind collecting section 87 that gradually inclines from the outer frame side toward the narrowest hole in the center. The reference number 88 indicates a power transmission shaft. The generator 85 itself can be made shorter in axial length to accommodate size and weight reduction.

An example of installing this thin generator unit 95 in an area that forms space, such as a slope on the road side, is shown in Figure 37. There are many places beside a road 99 that are mountains, plateaus, slopes of developed land, or vacant lots. In that place, two guide rails 96 with recesses 97 are inserted parallel to each other into the ground, and the thin generator unit 95 is installed between the recesses 97 with the protrusions 98 on both sides of the unit fitted together so that the blade surfaces face the road side (space side). This allows for effective use of the land. The generator unit 95 may receive wind from either the back or the front.

(5) Example of so-called propeller type installation Figure 38 shows another example of installation of a power generating facility using the power generating unit of the present invention in a so-called propeller type. A nacelle 123, which is a casing equivalent part, is arranged at the rear of the blades 120, which is arranged in an area 132 exposed to wind. The generator located in the nacelle 123 is connected to the blades 120 by a power transmission shaft 129. When the blades 120 are exposed to wind, they rotate, and the rotational force is transmitted to the nacelle 123 through the power transmission shaft 129. A speed increaser may be provided in the nacelle 123, but is not essential for the device of the present invention. The transmitted rotation is converted into electric power by a coreless type generator 127. The coil in the coreless type generator 127 is formed in a cylindrical shape (reference numeral 126), and the speed increaser and brake device 128 can be stored in the internal space (in the figure, these devices are arranged in series in order to simplify the explanation). The brake device 128 is responsible for suppressing or stopping the rotation during a strong wind or during inspection. However, the brake device 128 is not essential.

In this example, the power generating unit is installed on a support 131. The support 131 is hollow and cables pass through it. The electricity converted by the coreless generator 127 is then distributed through the support 131 via output cable 130 to the lead storage battery 133 or directly through output cable 134 to the user. Note that the present invention also includes cases where the voltage is increased via a transformer.

A coil connection switching board 125 is attached coaxially to the cylindrical coil body 126 of the coreless generator 127, and this coil connection switching board 125 and the cylindrical coil body 126 are connected by a connection wire 124. A monitoring communication device 122 (transmitter/receiver with antenna and sensor) and an anemometer 121 are attached to the top surface of the nacelle 123, and the monitoring communication device 122 is monitored at a monitoring center (not shown) on the ground (indoors), and the wind speed measured by the anemometer 121 is also transmitted to the brake device 128 and the coil connection switching board 125 via wiring (not shown).

(6) So-called vertical type installation example The present invention can be applied to both the horizontal axis type (propeller type, Dutch type, multi-blade type, etc., types in which the blades rotate around a horizontal axis) seen in each of the above installation examples, and the vertical axis type (Saponius type, Darrieus type, etc., types in which the blades rotate around a vertical axis).

Figure 39 shows an example where the blades 135 are arranged vertically (Darius type). The same symbols as in Figure 38 refer to the same parts. In this example, the generator is housed within a support 131 and is not exposed to the wind path. A power transmission shaft 129 projects from above the generator 126 into the sky, with multiple blades 135 arranged vertically, for example, so that they rotate when exposed to the wind from the side. If it is desired to increase the number of units, it is possible to install additional blades 135 in the vertical direction.

(7) Example of installation on the roof of a building Figure 40 shows an example of installation on the roof of a building 13, where (a) shows an example of installation on the corner of the roof, and (b) shows an example of installation along almost the entire circumference of the roof. When installing on a corner as in (a), it is possible to receive wind from all directions by placing two units at 90 degrees as shown. Also, if it is installed as in (b), it can also take the place of a rooftop fence (fence to prevent falls).

(8) Example of installation in a detached house Figure 41 shows an example of application to a detached house 14, where the wind power generator units 9 are arranged on the top of a fence to form part of the fence, but are also installed on the veranda. In this way, installation on a veranda or balcony is also effective. Reference numeral 15 denotes a solar panel that stores solar energy while the sun is out and stores wind energy while the wind is blowing, but it is of course possible to store both types of energy simultaneously.

(9) Example of using solar panels as a windbreak exterior wall Figure 42 shows an example of using solar panels 15 as a windbreak exterior wall. In this way, it is effective to install the solar panels 15 in one to three tiers in a row to surround the area where they are installed, thereby also providing wind protection for the area.

(10) Example of application to the coast Figure 43 shows an example of application to the coast 16, where it serves as a windbreak forest on the coast 16, and also serves as a windbreak wall for the coastline of a road 17. Reference numeral 5 denotes trees planted in the coastal area, and reference numeral 2 denotes wind from the sea. Sand passes through even if it enters the wind tunnel. An oil seal is placed on the main shaft of the coreless generator used to prevent sand from getting mixed in.

(11) Application to roads Figure 44 shows an example of installation in a median strip 18. As shown in the figure, in addition to natural wind 2, wind 4 generated by automobile travel also enters the wind power generator unit 9. Reference numeral 19 denotes a power storage facility, and reference numeral 20 denotes a charging station, and the power obtained from the wind power generator unit 9 can be stored in the power storage facility 19 for use. Note that wireless power transmission may be used for storing and charging these electricity.

As an example of a wireless power transmission facility, the power station 20 is provided with a power supply unit (a device that converts power into high frequency and receives an input signal to supply high frequency to the power supply head) and a power supply head connected to the power supply unit (a device that transmits power to the power receiving head non-contact using an electromagnetic coupling method and receives various signals from the power receiving head (on the mobile body such as a vehicle) and transmits them to the power supply unit), and the mobile body is provided with a power receiving head (a device that receives power from the power supply head and supplies power to the charging unit, and a device that transmits various signals output from the charging unit to the power supply head non-contact) and a charging unit connected to the power receiving head (a device that charges the battery of the mobile body, monitors the battery voltage, and outputs the results to the power receiving head and external control equipment connected to the unit).

(12) Application to bridges Figure 45 shows an example of application to a bridge. Although not limited to the type of bridge, locations where bridges exist are generally paths through which wind 2 passes, and are therefore suitable for installing the wind power generator units 9 of the present invention. In this example, a deck 23 is laid on the top surface of the main girder 22 spanning the bridge pier 21 to form a road 17, and the wind power generator units 9 are installed side-by-side on both sides of the deck 23. Reference numeral 24 denotes a tower and reference numeral 25 denotes a wire, both of which are bridge structures.

(Summary)
The height of the thin wind turbine generator units used in each of the above examples is set at 1.5 m, which does not obstruct the forward visibility of most users (especially if it is a skeleton), and also complies with the fence height (over 1.1 m) stipulated by Japan's Building Standards Act, for example.

In the above examples, no boost circuit or speed increasing means is used.
By installing multiple wind turbine generator units with coil connection switching function in the same area as in the above installation examples, the generated voltage of the group can be made uniform even if the wind strength of each wind turbine generator unit is different.

In addition, since this invention switches the induced voltage constant of the generator rather than switching the number of poles, if the rotation speed remains constant even after switching, the output voltage changes but the frequency does not. If the rotation speed is constant, the output voltage changes depending on the output current, but the frequency does not change depending on the output current. Therefore, it is possible to know the rotation speed of the generator by detecting the frequency. Incidentally, although coreless type generators are known, coil switching was not envisaged. The reason for this is that it is extremely difficult to increase the capacity of coreless type generators, and the idea of terminal switching on a coreless generator did not arise until a large-capacity coreless generator was developed.

Even if a cored motor is advertised as being suitable for light breezes, it does not rotate in light breezes because of cogging. Therefore, in order to accommodate light breezes, a motor or other speed-up means is sometimes used in combination (speed-up means are generally available). Generally, the voltage decreases in proportion to the weak wind speed, and the lower the voltage, the more difficult it is to extract output current. And electricity cannot be stored in a storage battery (for example, lead-acid batteries cannot store electricity below 8V). A coreless motor does not require a speed-up means because it is cogging-free, but if the voltage in the light breeze region is low, it is difficult to extract power, so a boost circuit is indispensable. Therefore, the coil that constitutes the generator is composed of multiple coil units, and the connection between the coil units can be switched between three or more stages, such as series, parallel, and series-parallel, making it possible to switch to increase the voltage even in light breeze regions, and this is the invention that makes it possible to extract power even in light breeze regions. It is known that coil connection switching can be performed in cored motors, but unless a speed-up means is also used, cored motors cannot realistically handle the gentle breeze region even if the coil connection is switched, and even if coreless motors can handle the gentle breeze region, they cannot generate enough power without the help of a boost circuit.

1...Blade, 2...Wind, 3...Generator, 4...Wind, 5...Tree, 6...Housing, 7...Coil connection switching board, 9...Wind turbine generator unit, 10...Foundation, 11...Wireless LAN device, 12...Wire, 13...Building, 14...House, 15...Solar panel, 16...Coast, 17...Road, 18...Central median strip, 19...Energy storage equipment, 20...Charging station, 21...Pier, 22...Main girder, 23...Deck slab, 24...Tower, 25...Wire, 31...Cylindrical coil body, 31a...Peripheral wall, 32...Outer yoke, 33...Inner yoke, 34...Bearing, 35...Permanent magnet , 36...shaft, 37...casing, 61...front portion, 2...rear portion, 63...air passage, 64...top portion, 65...bottom portion, 66...air collection portion, 67...beam, 68...side portion, 69...protective net, 71...control portion, 72...switch circuit portion, 80...triangular plate material, 81...frame, 82...beam, 311...virtual axis of cylindrical coil body, 312...single coil, 313...inner cylindrical coil body, 314...intermediate cylindrical coil body, 315...outer cylindrical coil body, 316...wire material, 317...fine copper wire, 318...enamel layer, 319...fibrous material, A, B...coil group, C, D...switch.

Claims (9)

The wind turbine comprises a generator having blades that rotate when exposed to wind, a rotating shaft that supports the blades, and a structure that houses the generator;
The generator includes at least a non-rotating cylindrical coil body, a yoke arranged cylindrically opposite the cylindrical coil body with a gap therebetween, and a permanent magnet arranged on a surface of the yoke facing the cylindrical coil body,
The cylindrical coil body is formed by connecting two coil groups in series, each of which has a plurality of coil units for a plurality of phases,
The coil group comprises coil group A equipped with a coil switching device that switches the connection pattern between the coil units to multiple stages selected from combinations of series, parallel, and series and parallel depending on the difference in rotational force of the blade caused by wind speed, and coil group B composed of a single wire that is thinner than coil group A, and the coil switching device automatically switches so that the system efficiency, calculated by the following formula based on the power change obtained according to the wind speed, becomes its maximum value.

2. The wind power generator unit according to claim 1, wherein the coil group A and the coil group B are wound in a cylindrical shape in a state of being adjacent to each other . a generator located on the wind path; blades attached to an outer circumferential rotating portion of the generator on the wind path; and a frame that houses the generator and the blades;
The air passage passes through the front and rear parts of the frame, and the generator and the blades are located on a through passage connecting the front and rear parts,
The generator has a shaft fixed to the frame and includes at least a non-rotating cylindrical coil body, a yoke arranged cylindrically opposite the cylindrical coil body with a gap therebetween, and a permanent magnet arranged on a surface of the yoke facing the cylindrical coil body,
The cylindrical coil body is formed by connecting two coil groups in series, each of which has a plurality of coil units for a plurality of phases,
The coil group comprises coil group A equipped with a coil switching device in which the connection pattern between the coil units is selected from combinations of series, parallel, and series and parallel depending on the difference in rotational force of the blade caused by wind speed, and switched between multiple stages, and coil group B composed of a single wire that is thinner than coil group A , and the coil switching device automatically switches so that the system efficiency, calculated by the following formula based on the power change obtained according to the wind speed, becomes its maximum value.

4. The wind power generator unit according to claim 3, wherein the coil group A and the coil group B are wound in a cylindrical shape in a state of being adjacent to each other . The wind power generator unit according to claim 3, characterized in that the frame has six rectangular faces, and the distance between the front and rear parts is shorter than each side of the front and rear parts, resulting in a thin-looking box body. In claim 5, the box body is formed of a frame, and right-angled triangular plate members are provided at the four corners of the front and rear parts,
The wind power generator unit is characterized in that the triangular plate members are arranged so that their right-angled apexes are located at the four corners of the front and rear portions . In claim 3, the wind power generator unit is characterized in that the yoke has an inner yoke arranged inside the cylindrical coil body and an outer yoke arranged outside the cylindrical coil body, the outer circumferential rotating part (peripheral surface) of the generator to which the blades are fixed forms a casing of the generator, and the casing is integrated with or serves as the outer yoke. A wind power generator unit cluster comprising a plurality of wind power generator units according to any one of claims 1 to 7 installed in an area exposed to the atmosphere, each of which is equipped with a wireless LAN transceiver for communicating the operating status of the unit, and a power storage facility to which the generated power output of each of the wind power generator units is transported. A wind power generator unit cluster facility according to claim 8, characterized in that the installation area is selected from the rooftops of buildings, verandas, balconies, fences, bridges, median strips of roads, roadsides, vacant lots, farmland, parks, railroad tracks, and coastlines.

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