JPS6024677B2 - Linear motor power supply method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power supply system for a linear motor and a power supply combination system for supplying power to a ground propulsion coil of a linear motor.

For linear motors, especially for ground primary type linear motors, the multiphase armature coil (primary coil) installed on the ground side
It is well known that a power converter supplies polyphase alternating current power of variable voltage and variable frequency to generate a moving magnetic field that matches the movement of a vehicle, thereby causing the vehicle to travel.

In this case, in order to prevent an increase in the reactive component of the supplied power and to prevent the power supply equipment from becoming too large, the armature coil should be divided appropriately and a switch should be connected to each divided armature coil. , a method is adopted in which power is supplied by switching the switches sequentially according to the movement of the vehicle. That is, an example is shown in FIG. CI and C2 are two three-phase power converters, and the power converter CI connects to the three-phase feeder line FI, and the power converter C2 connects to the three-phase feeder line F2, respectively, with variable voltage and variable frequency corresponding to the running of the vehicle. AC power is supplied. U1, V1,
WI is a three-phase unit armature coil (this will be referred to as a first unit armature coil), and is connected to the feeder line FI via a switching switch SWI. Similarly, U2, V2, W2 are the second
unit armature coils, U3, V3, W3 are third unit armature coils, U4, V4, W4 are fourth unit armature coils, which are adjacent in order from the first unit armature coils U1, V1, WI. It is arranged as follows. Each unit armature coil is alternately connected to feeder lines FI and F2 via switching switches SW2, SW3, and SW4. In such a conventional configuration, when the vehicle is traveling in the first unit armature coil section, the switching switch SWI is closed and the power converter CI is closed.
When the vehicle enters the second unit armature coil section, the switching switch SW2 is closed, the switching switch SWI is opened, and the power converter C2 is activated. The armature coils U2, V2, and W2 are excited by this.

In this way, the switching switches SW1, S are set according to the movement of the vehicle.
Switch W2, SW3, and SW4 sequentially to power converter C.
1 and C2 alternately supply power to the unit armature coils. In such a conventional configuration, the current of the feeder wires F1 and F2 that feed power to a large-capacity vehicle becomes large, making it uneconomical to install large-current-capacity feeder wires over a long distance.

As a countermeasure to this problem, it is possible to increase the voltage supplied to the feeder line, but due to restrictions in the insulation design of the armature coil or power converter, it is not possible to increase the voltage very high. On the other hand, if high voltage is supplied only to the feeder line through the transformer, there is a problem of transformer core saturation. In other words, the back electromotive force due to running vehicles is proportional to the frequency, but in linear motor railways, power is supplied over long distances and the unit length of the armature coil is large, so the resistance of the power supply line and armature coil becomes large. The ratio V/f of the output voltage V and frequency f of the power conversion device increases at low frequencies. As a result, the transformer core becomes saturated due to the low frequency range. This invention is intended to solve the problems of the above-mentioned conventional systems, and by switching the power feeding system in the low frequency range and the high frequency range, This makes it possible to supply power at the optimum feeder line voltage without any restrictions, thereby realizing economical feeder line equipment.

An embodiment of the present invention will be described below based on FIG. 2.

In Figure 2, CI and C2 are two three-phase power converters, and the power converter CI is switch SWII and transformer TR.
I1 to the three-phase power line FI, and the power converter C2
is connected to the three-phase power line F2 via the switch SW12 and the transformer TR12, and supplies variable voltage and variable frequency three-phase AC power corresponding to the running of the vehicle. U1, V1
, WI is a three-phase unit armature coil (this is called the first unit armature coil), and its input side terminals UI1, VI1
, WII are connected to the feeder line FI via the sliding door switch SWI and the transformer TRI, and to the power converter CI via the switch SW13. Similarly, U2, V2,
W3 is the second unit armature coil and its input terminal U21
, V21, W21 are switching switch SW2 and transformer TR2
U3, V3, W3 are the third unit armature coils, and their input terminals U31, V31, W31 are connected to the feeder line FI via the switching switch SW3 and the transformer TR3.
, U4, V4, and W4 are the fourth unit armature coils, and this unit armature coil is the terminal armature coil in the supply range of the power converters C1 and C2, and its input side terminal U41
, V41, W41 are switching switch SW4 and transformer TR4
are respectively connected to the feeder wire F2 via.

SW21 is a switch, and the first unit armature coil U1, V
1. This is for connecting between the neutral point side terminals U12, V12, and W12 of WI to form a three-phase star-shaped connection of the coils U1, V1, and WI. Similarly, the switch SW22 connects the neutral point side terminal U22 of the second unit armature coil U2, V2, W2,
Between V22 and W22, the switch SW23 connects the neutral side terminals U32 and V3 of the third unit armature coil U3, V3 and W3.
The switch SW24 connects between the neutral point side terminals U42, V42, and W42 of the fourth unit armature coils U4, V4, and W4, which are the terminal armature coils, respectively.
This is for making a star-shaped connection. The switch SW31 is for connecting the first unit armature coil U1, V1, WI and the second unit armature coil U2, V2, W2 in series, and is connected to the neutral point side terminal U12, V12, W12. Connect between side terminals U21, V21, and W21. Similarly, the neutral point side terminals U22, V22 of the second unit armature coil,
W22 and the input side terminal U31 of the third unit armature coil,
V31 and W31 are connected via switch SW32, and the neutral point side terminals U32, V32 of the third unit armature coil,
W32 and the input side terminal U41 of the fourth unit armature coil,
Connect between V41 and W41 via switch SW33.
As is clear from the above, the power converter CI. C2 has four sets of armature coils from the first to the fourth as its power supply range. Next, the operation of the device constructed as described above will be explained based on the embodiment shown in FIG.

First, in the region where the vehicle speed is low and the output frequency of the crane power conversion device is low, the switching switches SW1, SW2, SW3,
SW4 switch SWI1, SW12, SW21, SW22
, SW23 are opened, and switches SW13 and SW3 are opened.
1, by closing SW32, SW33 and the neutral point side switch SW24 of the terminal armature coil, the first, second,
The third and fourth unit armature coils are connected in series, and a voltage corresponding to the vehicle running speed is generated by the power converter CI.
Provides three-phase power of frequency. In this operating state, due to the influence of the resistance of the armature coil, the ratio V/f' between the output voltage V and the output frequency f of the power converter CI becomes a large value compared to the ratio V/f in the high frequency region. However, since the output of the power converter CI is supplied to the armature coil without going through the transformer, there is no concern about saturation of the transformer core. In addition, since the armature coils are connected in series, the value of inductance L becomes large, but since the operating frequency is low, the value of reactance x = 2 m L is small, and the back electromotive force due to the running of the vehicle is also 4.・Since it is short, the power supply voltage required to flow the rated current through the armature coil can be 4.
Furthermore, since the value of the back electromotive force caused by the running of the vehicle is small, the armature voltage required to cause the rated current to flow through the armature coil is low. Therefore, the output voltage of the power converter CI has a rating determined based on the conditions when the vehicle is at high speed, and there is no problem at all. In addition, in such an operating state, a large current is supplied from the power converter CI to the armature coil, but even when the vehicle is traveling far from the substation, the current is supplied via the armature coil. Since they are V-paid, there are no flea problems at all.
Next, as the vehicle running speed increases and the proportion of the back electromotive force of the linear motor in the overall voltage increases, the proportion of the influence of the power supply circuit resistance decreases, and the ratio V/f becomes smaller than the value in the low frequency region. It will be close to a constant value.

Therefore, in this operating state, for example, a frequency detection device (not shown) detects that the frequency has exceeded a certain specified value, and switches SW13, SW31, SW32
, SW33 is opened, and switches SWI1, SW12, SW are opened.
21, SW22, and SW23 are closed. Note that the switches SW24 of the terminal armature coils U4, V4, and W4 continue to remain closed. If the vehicle is present in the section of the first unit armature 1,000 coils U1, V1, WI, the switching switch SWI is closed, the switches SW2, SW3, SW4 are opened, and the vehicle is in the section of the second unit armature. Coil U2, V2,
When entering the W2 section, the switching switch SW2 is closed and the switching switch SWI is opened. In this way, as the vehicle travels, the sliding door switches SW1, SW2, SW3, and SW4 close only those corresponding to the unit armature coil where the vehicle is present, and the power converters C1 and C2 switch to one set of unit armature coils. Stay powered. In this operating state, the ratio V/
f maintains approximately the rated value, and there is no fear of saturation of the iron core even if power is supplied via a transformer. Therefore transformer TRI
By connecting 1, TR12, TR1, TR2, TR3, and TR4, the power supply voltage of the feeder lines F1 and F2 can be selected to the optimum value without any other restrictions. Therefore, the feeder line cost can be made economical by increasing the feeder voltage even for large-capacity vehicles. In the embodiment shown in FIG. 2, the case where four sets of three-phase unit armature coils are installed has been described above, but the present invention has the same effect on multi-phase unit armature coils of arbitrary plural sets. Of course, it is possible to obtain

In addition, transformers TRI1 and TR1 of the power converter output section
2 may be omitted if the output voltages of the power converters C1 and C2 can be designed to be high. As described above, according to the present invention, when the vehicle speed is low and the ratio V/f of the output voltage V of the power converter and the frequency f is large, the armature coils are connected in series to supply power to the armature coil, and the frequency f
When V/f increases and the ratio V/f decreases, the switch is switched in accordance with the movement of the vehicle to sequentially energize each unit armature coil, and the voltage of the armature coil is changed via a transformer.
Since the structure is configured to supply power at a high voltage, the current capacity of the power supply line can be reduced, and the power supply line for a near motor that requires the supply of large power over a long distance can be made economical.

The switching switch and the switch in the embodiment shown in FIG. 2 are not limited to mechanical structures, and may of course be electrical switches as long as they switch the power supply path to the unit armature coil. .

[Brief explanation of the drawing]

Figure 1 shows the conventional linear motor power supply system, Figure 2
The figure is a diagram showing an embodiment of a power feeding system for a linear motor according to the present invention. In the figure, U1, V1, WI are first unit armature coils, U2, V2, W2 are second unit armature coils, U3
, V3, W3 are the third unit armature coils, U4, V4,
W4 is the fourth unit armature coil, SW1, SW2, SW
3, SW4 is a switching switch, TR1, TR2, TR3, T
R4 is a transformer, SWI 1, SW12, SW13, SW
21, SW22, SW23, SW24, SW31, SW
32 and SW33 are switches, and CI and C2 are power converters. Note that the same reference numerals in the figures indicate the same or equivalent parts. 1st
Figure 2

Claims (1)

[Claims] 1. In a linear motor power feeding system in which power is supplied from a power converter to multiple sets of unit armature coils constituting a linear motor, a switching switch and a transformer are provided corresponding to each of the multiple sets of unit armature coils. In addition, a switch for connecting the plurality of unit armature coils in series is provided, and when the output frequency of the power converter is below a predetermined value, the switching switch is opened and the switching is performed. power is supplied from the power converter to the plurality of unit armature coils in series with the power converter closed, and when the output frequency of the power converter is above a predetermined value, the switch is opened and the switch is opened/closed. power is supplied to the unit armature coils via the transformer and the transformer, and the unit armature coils to be energized are sequentially switched to supply power according to the movement of the vehicle. A power supply method for linear motors.