JPH0116342B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a wind power generator, and particularly to one that controls the rotational speed of a wind turbine to be substantially constant. A wind power generation device uses a windmill to rotate a generator and convert the energy of the wind into electrical energy. Traditionally, wind power generators have been divided into so-called wind turbines, which increase the rotation speed of the wind turbine when the wind speed is high and slow it down when the wind speed is low, and those that keep the rotation speed of the wind turbine almost constant even when the wind speed changes. Some wind turbines use complex mechanisms to change the angle of attack of the blades or to change the plane of rotation of the wind turbine relative to the direction of the wind. However, in the former case, the rotational speed of the windmill changes greatly depending on the wind speed and the magnitude of the load, so in extreme cases, the rotational speed of the windmill may become excessive and the blades may be damaged. Also,
The latter has the disadvantage that it is expensive and has poor reliability due to its complicated mechanism, and that the recovery rate of wind energy decreases at high wind speeds. FIG. 1 is a graph showing the change in output with respect to the rotational speed of the wind turbine. v ₁ , v ₂ , v ₃ represent wind speed,
v ₁ < v ₂ < v ₃ . In other words, the output of the wind turbine increases as the wind speed increases, and under the same wind speed, the output of the wind turbine has a maximum point P _n , and in the region of low rotation speed, the output increases as the rotation speed increases, and the output of the wind turbine increases as the rotation speed increases. In a high range, the output tends to decrease as the rotational speed increases. The above-mentioned so-called wind power generation equipment generally has a load characteristic as shown by curve L in Figure 1, and under the same wind speed, the wind turbine output decreases as the rotation speed increases, resulting in a balance with the load. using a stable region. Also, when a wind turbine is used as a constant speed prime mover, a stable region as shown by n _sp in FIG. 1 is used, for example. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide a wind power generation device that can electrically control the rotational speed of a wind turbine to be substantially constant without using a complicated mechanism. To achieve this objective, the present invention provides a wind turbine and
In a wind power generation device including one generator driven by the wind turbine and a load electrically connected to the output circuit of the generator, individually inputting the load to the output circuit of the generator, A plurality of loads are connected so as to be disconnectable, and a detector detects the rotational speed of the wind turbine, and the plurality of loads are connected or disconnected according to the rotational speed of the windmill detected by the detector. A load control circuit for electrical control is provided,
The present invention is characterized in that the rotation speed of the wind turbine is controlled to be approximately constant in a region where the wind turbine output increases as the rotation speed increases at the same wind speed. In other words, in the wind turbine generator of the present invention, as shown in FIG. The rotational speed is controlled to be constant by controlling the on-off and on-off of multiple loads individually and adjusting the magnitude of the load on the generator. For example, in Figure 1, if n ₃ is the rated rotation speed, when the rotation speed is in the range n ₂ to _{n 4} , the size of the load connected to the generator remains unchanged, and n ₄ to n ₅ When the rotation speed reaches the range of , increase the load one by one until the rotation speed decreases, and if the load reaches n ₅ without increasing the load in time, apply the full load and force the rotation speed to decrease. ,
When it reaches the range of n ₁ to _{n 2} , the load is gradually decreased until the rotational speed increases, and if it still falls below n ₁ , the full load is cut off and the generator is put into no-load operation and rotated. Control is performed such as waiting until the speed reaches the rated speed. Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 shows an embodiment of the present invention, in which 1 is a wind turbine that converts wind energy into kinetic energy, 2 is a generator driven by the wind turbine 1, and 3 is a wind turbine that converts wind energy into kinetic energy.
is a pilot generator that detects the rotational speed of wind turbine 1; 4 is wind turbine 1, generator 2, pilot generator 3;
It is a structure that supports The rotating shafts of the wind turbine 1, generator 2, and pilot generator 3 are directly connected. As the generator 2, a synchronous generator or a DC generator can be used. 5 to 14 are each generator 2
A load to which power is supplied from, for example, a water heater heater or a battery, to which there is no problem even if the power supply is intermittent. Relays 15 to 18 are operated by the output voltage of the pilot generator 3, and have operating setting values as shown in FIG. That is, if the output voltage of the pilot generator 3 corresponding to the rated rotational speed of the wind turbine 1 is _V3 , then
The first relay 15 operates at a voltage V ₁ 10% lower than that, the second relay 16 operates at a voltage V ₂ 5% lower, and the third relay 17 operates at a voltage V ₄ 5% higher, The fourth relay 18 operates at a 10% higher voltage _V5 . Output voltage of pilot generator 3 V ₁ ~
V ₅ corresponds to the rotational speeds n ₁ to _{n 5} of the wind turbine in FIG. 1, respectively. Reference numeral 19 denotes a load control circuit that individually connects or disconnects the loads 5 to 14 to the output circuit of the generator 2 according to the operation mode of the relays 15 to 18. FIG. 4 shows a specific example of the load control circuit 19. In this figure, 15 to 18 are the aforementioned relays, +V,
-V is a constant voltage source, 20 to 23 are resistors, 24 to 31
is NOT, 32 to 35 are AND, 36 is an oscillator that generates a square wave at a constant cycle, 37 and 38 are NOR,
39, 40 are NOT, 41 is up-down counter, 42 is decimal counter, 43 is NOT, 44 is
AND, 45-53 are NOR, 54 is a switch, 55
-64 are NOR terminals, 65-73 are NOT terminals, and _L1 - _L10 are output terminals for load on/off signals corresponding to loads 5-14 in FIG. 2, respectively. Loads 5 to 14 each have a corresponding output terminal L ₁
When the signal from ~ _L10 is "0", it is applied to the output circuit of the generator 2, and when it is "1", it is disconnected from the output circuit. The output of the up-down counter 41 changes when the input to its UP or DOWN terminal changes from "0" to "1". That is, when a rectangular wave is sequentially input to the UP terminal, the outputs of the output terminals Qa to Qd change as shown on the left in Table 1, and the decimal counter 4
The output of 2 is inverted one by one from the terminal with the smaller number to the terminal with the larger number, and DOWN
When square waves are sequentially input to the terminal, the output terminal Qa
The output of ~Qd changes as shown on the right in Table 1, and the output of the decimal counter 42 is inverted one by one from the terminal with the larger number to the terminal with the smaller number.

[Table] The operation of this device is as follows. In the range where the rotational speed of the wind turbine 1 is low and all relays are off, that is, in the range of mode No. 1 in Fig. 3,
The output of NOT24 becomes “0”, therefore,
The output of NOT28, 29 is “1”, NOR45~5
The output of 3 becomes "0". Also, since the output of NOT27 is “0”, the output of NOR64 is “1”
becomes. Therefore, output terminals L ₁ to L ₁₀ are “1”
Therefore, the generator 2 is operated with no load. Next, when the rotational speed of the wind turbine 1 increases and enters the range where only the first relay 15 is on, that is, the range of mode No. 2 in FIG. 3, the output of NOT 24 becomes "1",
Since the output of NOT30 is also “1”, AND32
The output of is “1”, and AND34 is the oscillator 36
Outputs the same square wave as the output of . However, at this time, the output of AND33 is “0” continuously, and the output of NOT2 is “0”.
Since the output of NOT43 connected to the 0 terminal of the decimal counter 42 is "1", the output of NOT39 is continuously "1", and the operation of the up-down counter 41 is as follows. Locked. Therefore, even when changing from mode No. 1 to mode No. 2, the generator 2 remains in no-load operation. Furthermore, when the rotational speed of the wind turbine 1 increases and the first and second relays 15 and 16 are turned on and the others are turned off, that is, the range of mode No. 3 in FIG. 3 is reached, AND3
The output of 2 is “0”, the output of AND34 is also “0”,
The output of AND33 is continuously "1", and the output of NOT26 is continuously "0". For this reason, NOT
The outputs of 39 and 40 become "1" continuously, and the operation of up-down counter 41 is locked. Therefore, even if the mode changes to No. 1, No. 2, and No. 3, the generator 2 still remains in no-load operation. Furthermore, the rotational speed of the wind turbine 1 increases, and the
When the third relays 15, 16, and 17 are on and the others are off, that is, in the range of mode No. 4 in FIG. 3, the output of AND32 is "0", the output of AND33 is also "0", and AND34 is The output of is also “0” continuously,
Since the output of NOT26 becomes “1” continuously,
The output of the NOT 39 becomes "1" continuously, and the down operation of the up/down counter 41 is locked. On the other hand, since the output of NOT26 is continuously "1", AND35 outputs the same rectangular wave as the output of oscillator 36. This is NOR38, NOT40
Since the square wave is applied to the UP terminal of the up-down counter 41 through
Every time you enter, you advance one step. Decimal counter 42
has been 0 so far, so when one rectangular wave enters the up-down counter 41, the output of one terminal of the decimal counter 42 is inverted, the output of the output terminal _L1 becomes "0", and the second When a rectangular wave is input, the outputs of the two terminals are inverted, and the output of the output terminal _L2 becomes "0". In this way, the up-down counter 41
Each time a rectangular wave enters the UP terminal of the load control circuit 19, the output terminals L ₁ , L ₂ , L ₃ ... of the load control circuit 19 sequentially become "0", and loads 5, 6, 7 ... sequentially switch to the generator. 2 output circuit. While in the range of mode No. 4, loads are applied one after another until the rotation speed of the wind turbine 1 decreases. For example, the seventh load 11
When the rotation speed decreases and enters the range of mode No. 3, the up-down counter 4
The operation of 1 is locked there as described above,
Seven loads 5 to 11 remain turned on. Also, if the ninth load 13 is applied without the rotational speed decreasing, the switch 54 is connected to the input of NOR38.
Since "1" is continuously applied through the TM5-TM6 terminals, the operation of the up-down counter 41 is locked. Therefore, the generator 2 has nine loads 5
~13 are now connected. Even when nine loads 5 to 13 are applied, the rotational speed does not decrease and all relays 15 to 18 enter the on range, that is, the range of mode No. 5 in Fig. 3.
The output of NOR64 is “0”, through NOT73
The output of NOR63 is also “0”, similarly NOR62 to 5
The output of 5 also becomes "0", and the outputs of output circuits L ₁ to _{L 10} all become "0", and all loads 5 to 14
is injected. The load capacity is determined so that when all the loads are applied, the rotation speed of the wind turbine 1 decreases even if the wind speed is high. Therefore, when mode No. 5 is entered, the rotational speed of the wind turbine 1 decreases. The rotational speed continues to decrease in this state, and when it enters the mode No. 2 region, load shedding and cutting operations are performed. That is, in mode No. 2, as already explained, the AND 34 outputs the same rectangular wave as the output of the oscillator 36. At this time, all outputs other than AND34 connected to NOR37 are "0", so updown counter 4
A square wave is input to the DOWN terminal of 1. As a result, the decimal counter 42 advances by -1 step each time a rectangular wave is input, and each time the decimal counter 42 advances by one step, the load is cut off one by one.
When the rotation speed increases and enters the range of mode No. 3, the up-down counter 41
Since the operation of is locked there, the remaining five loads 5 to 9 remain turned on. Also, even if the load was cut off one after another, the rotation speed did not increase, and finally
When the 0 terminal output of the decimal counter 42 is inverted,
Since "1" is continuously applied to the input of NOR 37 through NOT 43, the operation of up-down counter 41 is locked. Therefore, in this state, the generator 2 is in no-load operation, and this state continues until the rotational speed reaches mode No. 4 as described above. In this way, the rotation speeds of the wind turbine 1 and the generator 2 are controlled to be in the range of mode No. 3, that is, approximately at the rated speed. As explained above, according to the present invention, a plurality of loads are connected to the output circuit of one generator so that they can be turned on and off individually, and the plurality of loads are By electrically controlling load input and output, the rotation speed of the wind turbine is kept almost constant, so there is no need for a complicated mechanism, and the rotation speed of the wind turbine can be kept almost constant electrically at low cost. It is also possible to improve the mechanical reliability of the device.

[Brief explanation of drawings]

Fig. 1 is a graph showing the rotational speed-output characteristics of a wind turbine, Fig. 2 is a block diagram of a wind power generation device according to an embodiment of the present invention, and Fig. 3 shows the operating state of the relay in the device of Fig. 2. The graph in FIG. 4 is a circuit diagram showing a specific example of the load control circuit in the device shown in FIG. DESCRIPTION OF SYMBOLS 1... Windmill, 2... Generator, 3... Pilot generator, 5-14... Load, 15... 18... Relay, 19... Load control circuit.

Claims (1)

[Claims] 1. In a device comprising a windmill, one generator driven by the windmill, and a load electrically connected to the output circuit of the generator, the load is individually connected to the output circuit of the generator. A plurality of loads connected in a manner that can be turned on and off, and a detector for detecting the rotational speed of the wind turbine, and a detector for turning on and off the plurality of loads according to the rotational speed of the windmill detected by the detector. A load control circuit for electrically controlling the wind turbine disconnection is provided, and the rotation speed of the wind turbine is controlled to be approximately constant in a region where the wind turbine output increases as the rotation speed increases at the same wind speed. Features of wind power generation equipment.