JP2023121223A - Railroad vehicle driving device and method therefor - Google Patents

Abstract

To provide a hybrid drive type railroad vehicle driving device that enables a power storage device for intermediate-voltage large-capacity use, to more safely distributing electric power also for low-voltage small-capacity use.SOLUTION: A railroad vehicle driving device comprises: an engine; an induction rotary machine engaged with the engine; a first power converter which, on one side, supplies/receives electric power to/from the induction rotary machine, meanwhile, which is, on the other side, interconnected with a main circuit DC part; a smoothing capacitor connected to a DC side of the first power converter; a second power converter which use the smoothing capacitor as a DC voltage source to drive or regenerate a driving rotary machine with AC; the driving rotary machine which the second power converter is interconnected with, and supplies/receives AC electric power to/from; a third power converter which is, on one side, interconnected with the main circuit DC part, meanwhile, which, on the other side, supplies/receives the AC electric power; a transformer which the third power converter supplies/receives the AC electric power and inputs/outputs the AC electric power to a primary side; a fourth power converter which, on one side, supplies/receives the AC electric power to/from a secondary side of the transformer, meanwhile, which, on the other side, supplying/receiving DC electric power; and a power storage device, which is connected to, and supplies/receives electric power to/from a DC side of the fourth power, wherein the smoothing capacitor is charged from the power storage device through the fourth power converter, the transformer and the third power converter.SELECTED DRAWING: Figure 1

Description

The present invention relates to a railway vehicle drive system and method thereof.

Patent Literature 1 discloses a hybrid railway vehicle in which the engine can be started using the secondary battery output. In this hybrid railway vehicle, an induction machine axially coupled to an engine and a medium-voltage large-capacity power storage device capable of driving the vehicle are connected to a DC section of a main circuit. Depending on the situation, the induction motor can be used as either a generator or an electric motor. To start the engine, when it functions as an induction motor, it is driven by the energy of the storage device, and when it functions as an induction generator, it is rotated by the engine. power output.

The engine generator can supply not only the driving power of the hybrid railway vehicle but also the charging power to the power storage device. In the hybrid railway vehicle of this configuration, the induction generator directly connected to the engine can also be used as the induction motor for starting the engine. At this time, the excitation current required for the induction motor is supplied from a power storage device connected to the main circuit.

Patent Document 2 discloses a non-hybrid, engine-powered railroad electric car equipped with only a low-voltage (for example, 110 V) and small-capacity power storage device, not a large-capacity power storage device for driving the vehicle. When the engine is started, even if the power storage device has a small capacity, the discharge power of the power storage device drives an induction generator directly connected to the engine as an induction motor. Such a low-voltage, small-capacity power storage device is mainly used as an on-vehicle device, and is wired at a low voltage to a place close to a human contact area. The low-voltage wiring is insulated against the main circuit DC section in order to prevent electric shock accidents and control equipment damage accidents.

JP-A-2008-49811 JP-A-2014-11828

The non-hybrid, engine-powered railroad electric car of Patent Document 2 is originally equipped with only one low-voltage, small-capacity power storage device, not a medium-voltage, large-capacity power storage device. Therefore, in order to distribute power to low-voltage on-board devices, there is no need for flexible bidirectional power interchange between the medium-voltage system and the low-voltage system. A more specific reason is that a low-voltage, low-capacity engine is enough to start the engine, and the function of converting medium-voltage regenerated electric power to low-voltage to charge a small-capacity storage battery is not provided. .

On the other hand, the medium-voltage large-capacity power storage device used in the hybrid railway vehicle of Patent Document 1 may be connected to the main circuit DC section, and its voltage to ground may be charged to a high voltage of the overhead line level. Therefore, stepping down the voltage and distributing it to a low-voltage on-board device has been restricted from the viewpoint of security. As a more specific reason, in addition to the control computer, in recent years, service outlets for passengers have also been listed as on-board equipment, but the damage caused by leakage of high voltage at the overhead line level to these vulnerable systems is not small. It is from.

Therefore, in the electric storage device used in the hybrid drive system, it is inevitable that the medium voltage large capacity system and the low voltage small capacity system are separated from each other and provided independently of each other. However, in the hybrid drive system, a medium-voltage large-capacity power storage device is provided as a main power source. If so, it is desirable from the viewpoint of facility efficiency to step down the medium voltage and distribute the power to the low voltage on-board equipment so that both the high and low voltages are combined. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and its object is to provide a hybrid drive railway vehicle capable of safely distributing electricity from a medium-voltage, large-capacity power storage device to a low-voltage, small-capacity power storage device. It is an object of the present invention to provide a driving device for

The present invention, which solves the above problems, is a hybrid railway vehicle drive system comprising: an engine; an induction rotating machine engaged with the engine; A first power converter capable of bi-directional conversion of AC and DC linked to the circuit DC part with DC, a smoothing capacitor connected to the DC side of the first power converter, and a driving rotating machine using the smoothing capacitor as a DC voltage source. A second power converter capable of bi-directional conversion of AC and DC that is driven or regenerated by the second power converter, a driving rotating machine that is interconnected by giving and receiving AC power, and a main circuit DC part that is interconnected with DC , on the other hand, a third power converter capable of bi-directional conversion of AC and DC that transfers and receives AC power, a transformer that transfers and receives AC power and inputs and outputs to the primary side, and a secondary side of the transformer on the other hand a fourth power converter capable of bi-directional AC/DC conversion that transfers AC power to and receives DC power from the other; and a power storage device that is connected to the DC side of the fourth power converter and transfers DC power, The power storage device charges the smoothing capacitor through the fourth power converter, the transformer, and the third power converter.

According to the present invention, it is possible to provide a railway vehicle drive system of a hybrid drive system that can more safely distribute electric power from a medium-voltage, large-capacity power storage device to a low-voltage, small-capacity power storage device.

1 is a block circuit diagram showing a schematic configuration of a railway vehicle drive device (hereinafter also referred to as "this device") according to an embodiment of the present invention; FIG. 2 is a timing chart showing changes in voltage and current at each part when the device shown in FIG. 1 is started. FIG. 2 is a circuit diagram showing in detail a connection form between a power converter and a transformer; 4 is a timing chart of voltage waveforms at each part when the primary side V1 and secondary side K·V2 of the transformer shown in FIG. 3 are switched with a phase difference α=0; FIG. 5 is a timing chart of voltage waveforms at each part when switching is performed with a phase difference α>0 in contrast to FIG.

Hereinafter, the embodiments of the present invention will be supplemented in detail after the outline is described first. FIG. 1 is a block circuit diagram showing a schematic configuration of the device 19. As shown in FIG. As shown in FIG. 1, the hybrid drive system 19 includes a power storage device 6 with a medium voltage (for example, 1500 V) capacity capable of driving a railway vehicle (hereinafter also referred to as "vehicle") (not shown). This power storage device 6 discharges the power stored therein and supplies it to the main circuit DC section. The main circuit DC section here is a high voltage charging section that is most likely to be connected to the overhead wire, and can be considered as a DC section measurable by the PT1 power sensor 13 .

On the other hand, depending on the operation mode of the vehicle, the electric power generated by the induction generator (induction rotating machine) 2 driven by the engine 1 is charged to the power storage device 6 via the main circuit DC section. Alternatively, the regenerated power is charged to the power storage device 6 via the main circuit DC section according to the operating state. A transformer 10 is interposed in the path through which the power storage device 6 is charged and discharged in this manner. A necessary dielectric strength is ensured between the primary side coil and the secondary side coil of the transformer 10 . The "induction generator 2" and the "induction motor 2" correspond to the "induction rotating machine" in the present invention.

Further, the electric power for driving the induction motor (induction rotating machine) 2 that starts the engine 1 is far less than the electric power required for driving the vehicle. Therefore, if it is for starting the engine 1, even a small capacity is sufficient, so a low-voltage, small-capacity storage battery for on-vehicle equipment (not shown) is also sufficient. Therefore, for such applications, a large-capacity power storage device 6 can be used as much as possible.

However, from the viewpoint of equipment efficiency that "large and small are both large and small" rather than "large and small", even for starting the engine 1, which requires a small capacity, if a large-capacity power storage device 6 is also used, a small-capacity power storage device can be used. This eliminates the need for a small storage battery, and increases the facility efficiency as a railway vehicle drive system. As an example, the withstand voltage performance of the power storage device 6 may be equivalent to a medium voltage DC 1500 V output, and may be lower than the voltage of the main circuit DC section, which is equivalent to a high voltage DC 3000 V as an example of overhead wire voltage, or may be equivalently high. Also good.

In the configuration of FIG. 1, the power storage device 6 is connected to the main circuit DC section so as to allow bidirectional power transfer while ensuring insulation. There is a voltage difference of about 1500V between the main circuit DC portion measured by the PT1 power sensor 13 as a high voltage of DC 3000V and the power storage device 6 measured by the PT2 power sensor 15 as a medium voltage of DC 1500V. This voltage difference can be exchanged while the insulation is maintained by the insulation voltage between the primary side coil and the secondary side coil of the transformer 10 .

Also, in a certain operation mode, if the electric power stored in the power storage device 6 is suddenly supplied to the main circuit DC section, an overcurrent will flow, and there is a possibility that circuit elements such as the switching elements 17 to 24 (FIG. 3) will be destroyed. be. Therefore, the controller 16 controls the power converters 8, 9, etc. so as to gradually flow the current, thereby avoiding damage to the circuit elements.

As described above, in one operation mode, the vehicle is driven while charging the medium-voltage large-capacity power storage device 6 insulated from the main circuit DC part with the power generation output of the induction machine 2 driven by the engine 1, , the outline of the present device 19 capable of starting the engine 1 in addition to driving the vehicle with the electric power of the power storage device 6 has been described.

In the following, the device 19 will be described in more detail, although there is overlap. As shown in FIG. 1, the device 19 includes an engine 1, an induction generator 2 driven by the engine 1, and a converter (first converter) for converting AC power output from the induction generator 2 into DC power. a power converter) 3, a smoothing capacitor 5 that smoothes the DC power output from the converter 3 and connects it to the main circuit DC section, and an inverter device that uses the smoothing capacitor 5 as a DC voltage source and converts it to AC power. 2 power converter) 4 and an electric motor (driving rotary machine) 11 driven by the inverter device 4 .

This device 19 further includes a smoothing capacitor 14 connected in parallel to the large-capacity storage device 6 via a contactor 7, a PT2 voltage sensor 15 for measuring the voltage of the smoothing capacitor 14, and a DC power of the smoothing capacitor 14. A power converter (fourth power converter) 9 that converts to AC, a transformer 10 that transforms the AC output voltage of the power converter 9, and a power converter that converts the AC power of the transformer 10 to DC (Third power converter) 8, a contactor 12 that supplies the power converted by the power converter 8 to the smoothing capacitor 5, a PT1 voltage sensor 13 that measures the voltage of the smoothing capacitor 5, and A control unit 16 for inputting information and controlling the power converter 8 and the power converter 9 is provided.

The power storage device 6 can store not only the power generated by the induction generator 2 but also the power regenerated by the electric motor 11 during deceleration of the vehicle. Also, during acceleration of the vehicle, the power storage device 6 can discharge the power stored therein and supply power for driving the electric motor 11 . The "electric motor 11" corresponds to the "driving rotary machine" of the present invention, and functions as a generator during regenerative power generation.

Next, the procedure of the railway vehicle driving method according to the embodiment of the present invention will be described with reference to FIG. As an example of the state transition, when both the engine 1 and the vehicle are stopped, the induction motor 2 is driven, the engine 1 shaft-coupled thereto is started, and the induction generator 2 is thereby driven, thereby generating AC power is rectified into DC by the converter 3, and the DC power is used by the inverter 4 to generate three-phase AC, which drives the electric motor 11 to rotate the wheels (not shown) to propel the vehicle.

FIG. 2 is a timing chart showing changes in the voltage and current of each part when the device 19 shown in FIG. 1 is started. In FIG. 2 , the horizontal axis indicates common time, and the vertical axis indicates, from top to bottom, battery current Ib, voltage FC2 of smoothing capacitor 14, voltage FC1 of smoothing capacitor 5, excitation of induction generator 2. For the six items of the current (Excitation current of induction generator 2) Ig, the torque current of induction generator 2 (Torque current of induction generator 2) It, and the startup status of the inverter device 4 (Inverter 4 startup status), each transient phenomenon. The states will be described below at timings (1) to (5) in FIG.

(1) Charge FC1 at the same time as FC2. That is, when charging the smoothing capacitor 14 , the control unit 16 simultaneously charges the smoothing capacitor 5 by controlling the power converter 9 and the power converter 8 .

(2) Excitation current is applied at the start of converter operation (Converter operation started→Excitation current applied). That is, the control unit 16 makes the voltage of the smoothing capacitor 5 equal to or higher than the voltage (A[V]) sufficient to excite the induction generator 2 . That is, control unit 16 stores energy in smoothing capacitor 5 via converter 3 . The energy is more power than the induction generator 2 can generate the excitation current Ig and the torque current It required for power generation. At the timing (2) when it reaches that point, the converter 3 converts the voltage of the smoothing capacitor 5 into alternating current and starts to flow the excitation current Ig to the induction generator 2 .

(3) Converter constant voltage operation started. That is, the control unit 16 causes the converter 3 to raise the torque current It of the induction generator 2 to start constant voltage control. Thus, the induction generator 2 starts generating power. After that, the voltage of the smoothing capacitor 5 is raised to a predetermined voltage (B[V]) and maintained by the power generated by the induction generator 2 .

(4) FC1 charge completed (FC1 charge completed). That is, when the voltage of the smoothing capacitor 5 rises to a predetermined voltage (B[V]), the control unit 16 performs constant voltage control on the converter 3 to keep the torque current It of the induction generator 2 constant. As a result, the voltage of the smoothing capacitor 5 is maintained at B[V].

(5) Inverter 4 starts.

Here, the power storage device 6 is not a low-voltage, small-capacity compact storage battery for supplying power to on-board control devices, but a group of medium-voltage, large-capacity storage batteries that can store medium-voltage power generated during regeneration. .

By setting the turns ratio N (N = [number of turns on the primary side (main circuit side)]/[number of turns on the secondary side (battery side)]) of the transformer 10 to 1 or more, the voltage is higher than the battery voltage. It is possible to charge the smoothing capacitor 5 . Furthermore, it is also possible to charge the smoothing capacitor 5 to a voltage higher than the withstand voltage of the power storage device 6 .

FIG. 3 is a circuit diagram showing in detail the connection form of the power converters 8, 9 and transformer 10. As shown in FIG. The power converter 8 is a full bridge circuit composed of switching elements 17 to 20, and the power converter 9 is composed of switching elements 21 to 24, respectively. Coil 26 provides a smoothing action in conjunction with smoothing capacitor 14 (FIG. 1).

By controlling the on/off of the switching elements 21 to 24, the voltage V1=V1u-V1V applied to the primary side of the transformer 10 and the voltage V2=V2u-V2V applied to the secondary side of the transformer 10 are controlled. do. Here, the turns ratio of transformer 10=N:1=1:K.

FIG. 4 is a timing chart of voltage waveforms of the transformer 10 shown in FIG. 3 when the primary side V1 and the secondary side K·V2 are switched with a phase difference α=0. In FIG. 4, the phase difference between phases is 180°. When there is no potential difference between K·V1, which is the primary voltage V1 converted to the secondary side, and the secondary voltage V2, and the phase difference α is 0, the power converted between the primary side and the secondary side is 0. As a result, charging and discharging of the power storage device 6 are not performed. In the graph at the bottom of FIG. 4, when K·V1−V2=0, the amplitude is shown to be small for convenience of explanation.

FIG. 5 is a timing chart of voltage waveforms at each part when switching is performed with a phase difference α>0 with respect to FIG. That is, as shown in FIG. 5, the primary side V1 and the secondary side K·V2 of the transformer 10 are switched with a phase difference α>0. At this time, the power converted from the primary side to the secondary side becomes positive, and the power storage device 6 is charged.

On the other hand, if the phase difference α<0, the power converted from the primary side to the secondary side becomes negative, and the power storage device 6 is discharged. In this way, the direction and amount of current are controlled by changing the polarity of the phase difference α, switching the phase advance and delay, and adjusting the phase, so that the charge and discharge of the power storage device 6 can be conveniently controlled by the hybrid drive control method. conduct.

The transfer of energy that occurs when accelerating or decelerating a railway vehicle will be described. First, at the time of acceleration, the driving AC motor 11 receives power generated by the induction generator 2 or power discharged from the power storage device 6, and increases the rotational speed while generating power running torque. At this time, the control unit 16 controls the power converters 9 and 8 to move the power discharged from the power storage device 6 in the discharge direction, thereby supplying the power to the drive AC motor 11 . That is, the vehicle may be powered by at least one of the generated power and the discharged power, depending on the driving conditions.

In driving conditions other than acceleration of the vehicle, the control unit 16 controls the power converters 8 and 9 to generate surplus power generated by the induction generator 2, or power generated by the drive AC motor 11 during deceleration. The regenerated power is moved in the charging direction and stored in the power storage device 6 . Thus, the control unit 16 charges the large-capacity storage battery 6 with the power generated by the induction generator 2 and the drive AC motor 11 via the power converter 8, the transformer 10, and the power converter 9. That is, the control unit 16 may charge with at least one of the generated power and the regenerated power according to the operating conditions of the vehicle, but may stop the engine or may select not to charge.

Conversely, the control unit 16 discharges the large-capacity storage battery 6 according to the driving conditions of the vehicle, and supplies power to the induction generator 2 and the driving AC motor through the power converter 9, the transformer 10, and the power converter 8. 11 to supply driving power. According to this device 19 , the control section 16 controls the phase difference α, so that power can be exchanged efficiently between the main circuit DC section and the storage device 6 . As a result, the vehicle to which the device 19 is applied can take advantage of the advantages of the hybrid drive system.

The railway vehicle driving device (this device) according to the embodiment of the present invention can be summarized as follows.
[1] The device 19 shown in FIG. It includes a capacitor 5 , a transformer 10 , and a medium-voltage (for example, 1500 V) large-capacity power storage device 6 .

The induction rotating machine 2 and the driving rotating machine 11 can selectively operate as an induction generator or an induction motor according to operating conditions. Further, the induction rotating machine 2 is axially coupled to the engine 1, and is in a relationship of mutual use of driving force and electric power according to either the engine starting state or the engine generator state.

The first power converter 3 (converter) exchanges AC power with the induction rotating machine 2 on the one hand, and connects with the DC part of the main circuit on the other hand with DC to convert AC and DC in both directions. The smoothing capacitor 5 is connected to the DC side of the first power converter 3 and is linked to the main circuit DC section by DC. A second power converter (inverter) 4 transfers and receives AC power to the driving rotary machine 11 for interconnection. The second power converter 4 is capable of bi-directional AC/DC conversion, and uses the smoothing capacitor 5 as a DC voltage source to drive or regenerate the driving rotary machine 11 with AC. It should be noted that if the main circuit DC section is interconnected by DC, it is assumed that the DC voltage close to the overhead line voltage is shared so that power can be mutually interchanged.

The third power converter 8 is capable of bi-directional AC/DC conversion, and on the one hand is linked to the main circuit DC section by DC, and on the other hand it gives and receives AC power. In the transformer 10, the third power converter 8 delivers and receives AC power, and performs input/output on the primary side. The fourth power converter 9 is capable of bi-directional AC/DC conversion, and transfers AC power to the secondary side of the transformer 10 on the one hand and DC power on the other. The power storage device 6 is connected to the DC side of the fourth power converter 9 to exchange DC power. This device 19 charges the smoothing capacitor 5 from the power storage device 6 via the fourth power converter 9 , the transformer 10 and the third power converter 8 .

The device 19 of [1] above insulates the medium-voltage large-capacity power storage device 6 for hybrid driving from the high-voltage main circuit direct-current section via the transformer 10 . Therefore, the power storage device 6 connected to the secondary side of the transformer 10 is insulated from the main circuit DC section and overhead line high voltage section (eg, 3000 V) connected to the primary side of the transformer 10 .

As a result, the medium-voltage large-capacity power storage device 6 of the device 19 can be prevented from being directly connected to the most dangerous overhead line level high voltage. Therefore, the device 19 can more safely distribute power from the medium-voltage, large-capacity power storage device 6 to low-voltage, small-capacity applications. It should be noted that the illustration of distribution lines from the medium-voltage power storage device 6 to low-voltage on-board devices and the like is omitted.

In addition, from the viewpoint of safety, since the power storage device 6 of the present device 19 is not directly connected to the overhead wire, there is no possibility of a fire caused by an abnormally large current flowing from the overhead wire. The larger the capacity of the power storage device 6, the greater the damage of a fire accident in the unlikely event that it should occur.

[2] In the above [1], by controlling the phase difference α between the voltage of the third power converter 8 and the voltage of the fourth power converter 9, the primary side and the secondary side of the transformer 10 A controller 16 was also included which was capable of controlling the amount and direction of power transfer between them. This control unit 16 can also charge the power storage device 6 with regenerated electric power during braking.

According to this device 19, power can be exchanged efficiently between the main circuit DC section and the electricity storage device 6 mutually. In this power interchange, the power storage device 6 can be charged with the surplus power generated by the induction generator 2 generated by the driving force of the engine 1 and the regenerated power. It can be freely realized by controlling the phase difference α.

[3] In [2] above, the control unit 16 sets the phase difference α to 0 at the start of control. If the phase difference α is 0, the amount of power transfer between the primary and secondary sides of the transformer 10 is maintained at 0, so the device 19 mitigates the inrush current at start-up and Realize stable start of control by gradual startup.

[4] In [2] above, the control unit 16 performs different controls depending on whether the engine 1 is not operating or operating. The control unit 16 controls the constant voltage of the fourth power converter 9 to which power is supplied from the power storage device 6 when the engine 1 is not operating in a state in which external power such as overhead power cannot be obtained. As a result, the device 19 outputs power at a constant voltage and creates a pseudo state in which external power such as overhead power is obtained, thereby stably driving the railroad vehicle. As a result, the device 19 can realize more stable running by taking advantage of the hybrid drive system.

Further, the control unit 16 controls the constant voltage of the first power converter 3 to supply a voltage close to the rated voltage of the overhead wire, etc., when the engine 1 is operating instead of the external power such as the overhead wire in a state where external power cannot be obtained. maintain. As a result, the railway vehicle is supplied with electric power as much as necessary for running. If there is surplus power, the control unit 16 inputs it to the fourth power converter 9 at a low voltage, and the fourth power converter 9 performs constant current control to supply an appropriate charging current to the power storage device 6. . As a result, the present device 19 enables long-distance running in a non-electrified section using only the power storage device 6, thereby further reducing fuel consumption.

[5] In [1] above, the breakdown voltage of the smoothing capacitor 5 is set higher than that of the power storage device 6 . The smoothing capacitor 5 is connected to the DC part of the main circuit and can withstand the highest voltage equivalent to the overhead line voltage. If the medium-voltage power storage device 6 has a capacity to drive the vehicle, its voltage may be less than half of that of the overhead wire or main circuit DC section, and the voltage shortage is distributed between the primary side and the secondary side of the transformer 10. can be easily adjusted by the voltage ratio depending on the turns ratio.

[6] In the above [2], in FIG. 1, the control unit 16 controls the phase difference between the third power converter 8 and the fourth power converter 9 under the condition that the respective frequencies are the same. Add or subtract Thereby, the switching frequencies of the switching elements 17 to 24 provided in both can be made uniform. As a result, the lifetimes of all the switching elements 17-24 can be made uniform.

[7] A hybrid railway vehicle driving method (this method) according to an embodiment of the present invention has the following operations. However, the operation procedure is changed as appropriate depending on the driving conditions of the vehicle. First, there is a case where the induction rotating machine 2 axially coupled to the stopped engine 1 is started by being driven as an induction motor.

In some cases, the induction rotating machine 2, which is axially coupled to the engine 1 that is being driven, generates alternating current as an induction generator. Also, a first power converter 3 capable of bi-directional conversion of AC and DC supplies and receives AC power to and from the induction rotating machine 2 on the one hand, and connects to the main circuit DC section on the other hand. A smoothing capacitor 5 is connected to the DC side of the first power converter 3 and the main circuit DC section. In addition, the second power converter 4 capable of bi-directional conversion of AC and DC drives or regenerates the drive rotating machine 11 with AC using the smoothing capacitor 5 as a DC voltage source.

A third power converter 8 capable of bi-directional conversion of AC and DC is connected to the DC part of the main circuit with DC on the one hand, and exchanges AC power with the primary side of the transformer 10 on the other hand. Further, a fourth power converter 9 capable of bidirectional conversion of AC/DC transfers AC power to and receives AC power from the secondary side of the transformer 10 on one side, and DC power to and from the other side.

Also, the power storage device 6 is connected to the DC side of the fourth power converter 9 to exchange DC power. Also, the smoothing capacitor 5 is charged from the power storage device 6 via the fourth power converter 9 , the transformer 10 and the third power converter 8 . According to this method, power can be more safely distributed from the medium-voltage, large-capacity power storage device 6 to the low-voltage, small-capacity power storage device. Also, power can be exchanged efficiently between the main circuit DC section and the electricity storage device 6 .

DESCRIPTION OF SYMBOLS 1... Engine, 2... Induction generator, 3... Converter (first power converter), 4... Inverter (second power converter), 5... Smoothing capacitor, 6... (Large-capacity) power storage device, 7, 12 ... contactor, 8, 9 ... third and fourth power converters (Power converter), 10 ... transformer, 11 ... electric motor (driving rotary machine), 13, 15 ... PT1, PT2 voltage sensor, 14 ... smoothing capacitor , 16... Controller, 17 to 24... Switching element, Ib... Battery current, Voltage, α... Phase difference, 19... Rail vehicle drive device (this device)

Claims (12)

A hybrid railway vehicle drive device,
engine and
an induction rotating machine engaged with the engine;
a first power converter capable of bi-directional conversion of alternating current and direct current, which exchanges electric power with the induction rotating machine on the one hand and connects with the main circuit direct current part on the other hand with direct current;
a smoothing capacitor connected to the DC side of the first power converter;
a second power converter capable of bi-directional conversion of AC and DC for driving or regenerating a driving rotary machine with AC using the smoothing capacitor as a DC voltage source;
a driving rotating machine to which the second power converter exchanges and receives AC power and is interconnected;
a third power converter capable of bi-directional conversion of alternating current and direct current, which is connected to the main circuit direct current part by direct current on the one hand and exchanges alternating current power on the other hand;
a transformer through which the third power converter exchanges AC power and inputs/outputs the AC power to/from the primary side;
a fourth power converter capable of bi-directional conversion of alternating current and direct current, which exchanges alternating current power on the one hand with the secondary side of the transformer and exchanges direct current power on the other hand;
a power storage device connected to the DC side of the fourth power converter to exchange DC power;
with
charging the smoothing capacitor from the power storage device through the fourth power converter, the transformer and the third power converter;
Drive system for railway vehicles. the amount of power transferred between the primary and secondary sides of the transformer by controlling the phase difference between the voltage of the third power converter and the voltage of the fourth power converter; It further comprises a control unit that can control the direction and
The power storage device can also store regenerated power during braking.
The railway vehicle drive system according to claim 1 . The control unit has a phase difference of 0 at the start of control,
The railway vehicle drive system according to claim 2 . The control unit
When the engine is not operating, the fourth power converter performs constant voltage control,
During operation of the engine, the first power converter is under constant voltage control, and the fourth power converter is under constant current control.
The railway vehicle drive system according to claim 2 . The dielectric strength of the smoothing capacitor is set higher than that of the power storage device,
The railway vehicle drive system according to claim 1 . The control unit adjusts the phase difference between the third power converter and the fourth power converter under the condition that the respective frequencies are the same.
The railway vehicle drive system according to claim 2 . A hybrid railway vehicle drive method comprising:
An engine in a stopped state is started by driving an induction rotating machine engaged with the engine as an induction motor,
an induction rotating machine engaged with the engine being driven generates alternating current as an induction generator;
a first power converter capable of bidirectional conversion of alternating current and direct current, on the one hand giving and receiving alternating current power to the induction rotating machine, and on the other hand connecting to the main circuit direct current part,
A smoothing capacitor is connected to the DC side of the first power converter and the main circuit DC part,
A second power converter capable of bi-directional conversion of AC and DC uses the smoothing capacitor as a DC voltage source to drive or regenerate a drive rotating machine with AC,
A third power converter capable of bi-directional conversion of alternating current and direct current is connected to the main circuit direct current part with direct current on the one hand, and exchanges alternating current power with the primary side of the transformer on the other hand,
A fourth power converter capable of bi-directional conversion of alternating current and direct current exchanges alternating current power with the secondary side of the transformer on the one hand, and exchanges direct current power on the other hand,
a power storage device linked to the DC side of the fourth power converter to exchange DC power;
charging the smoothing capacitor from the power storage device through the fourth power converter, the transformer and the third power converter;
A drive method for a railway vehicle. A control unit controls the phase difference between the voltage of the third power converter and the voltage of the fourth power converter, so that power is generated between the primary side and the secondary side of the transformer. By controlling the amount and direction of movement,
The power storage device can also store regenerated power during braking,
The railway vehicle driving method according to claim 7 . The control unit sets the phase difference at the start of control to 0,
The railway vehicle driving method according to claim 8 . The control unit
When the engine is not operating, the fourth power converter performs constant voltage control,
During operation of the engine, the first power converter is under constant voltage control, and the fourth power converter is under constant current control.
The railway vehicle driving method according to claim 8 . The dielectric strength of the smoothing capacitor is set higher than that of the power storage device,
The railway vehicle driving method according to claim 7 . The control unit adjusts the phase difference between the third power converter and the fourth power converter under the condition that the respective frequencies are the same.
The railway vehicle driving method according to claim 8 .

Images