Power supply device for railway vehicle

Abstract

A power supply device (5) for a railway vehicle according to the present invention is mounted on a railway vehicle (110) provided with a battery (9). Comprising a chopper circuit (21) disposed on the primary side of a transformer (28), a first inverter (24) disposed between the chopper circuit (21) and the transformer (28), a resonance circuit (25) disposed between the first inverter (24) and the transformer (28), and a second inverter (26) disposed between the transformer (28) and a DC load (6). The chopper circuit (21) performs a step-down operation during normal travel, and performs a step-up operation during emergency travel. The first inverter (24) converts the DC voltage applied from the chopper circuit (21) into an AC voltage, and converts the AC voltage applied from the primary side of the transformer (28) into a DC voltage. The second inverter (26) converts an AC voltage applied from the secondary side of the transformer (28) into a DC voltage, and converts a DC voltage applied from the battery (9) into an AC voltage.

Description

Technical Field

[0001] The present disclosure relates to a power supply device for a railway vehicle mounted on a railway vehicle including a storage battery. Background Art

[0002] The following patent document 1 discloses a power supply device for railway vehicles, which converts the DC power supplied from the DC overhead line into AC power by using an inverter, insulates it by using an LC filter composed of a reactor and a capacitor and a commercially available insulation transformer, and then converts it into 50 / 60 [Hz] three-phase AC power or single-phase AC power required for auxiliary machines such as cooling and heating devices and display devices. In addition, auxiliary machines refer to the name of equipment other than propulsion motors that are installed in railway vehicles and provide power. In addition, in railway vehicles, the power supply device that drives the propulsion motor is called a "main conversion device" or the like, and is provided separately from the power supply device that supplies power to the auxiliary machines.

[0003] In addition, as a recent technical trend, there is a railway vehicle system equipped with a storage battery, which is configured to continue to supply power to auxiliary machines using the power of the storage battery in an emergency such as an overhead line power failure. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2017-38424 Summary of the invention Technical problem to be solved by the invention

[0005] There is also a demand to use the power of the battery that supplies power to the auxiliary machine in an emergency as power for emergency driving. However, like the power supply device of the above-mentioned Patent Document 1, the flow of power in the power supply device that supplies power to the auxiliary machine is a one-way flow from the overhead line to the auxiliary machine, which cannot meet this demand.

[0006] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a power supply device for a railway vehicle that can utilize the power of a battery that supplies power to an auxiliary machine as power for emergency running. Technical means for solving technical problems

[0007] In order to solve the above problems and achieve the purpose, the power supply device for railway vehicles involved in the present disclosure is mounted on a railway vehicle equipped with a battery, and includes a transformer that insulates the primary side and the secondary side. The power supply device for railway vehicles includes a chopper circuit configured on the primary side of the transformer, a first inverter configured between the chopper circuit and the transformer, a resonant circuit having a resonant capacitor and configured between the first inverter and the transformer, and a second inverter configured between the transformer and the DC load. The chopper circuit performs a step-down operation when power is supplied from the overhead line side, and performs a step-up operation when power is supplied from the battery side. The first inverter converts the DC voltage applied from the chopper circuit into an AC voltage and applies it to the primary side of the transformer, and converts the AC voltage applied from the primary side of the transformer into a DC voltage and applies it to the chopper circuit. The resonant circuit performs a series resonant operation through the capacitance component and the inductance component of the resonant capacitor. The second inverter converts the AC voltage applied from the secondary side of the transformer into a DC voltage and applies it to the DC load and the battery connected in parallel with the DC load, and converts the DC voltage applied from the battery into an AC voltage and applies it to the secondary side of the transformer. The power supply device for a railway vehicle is configured to supply power to auxiliary machines using power from overhead wires during normal travel, and to supply power to auxiliary machines and a main motor mounted on the railway vehicle using power from a battery during emergency travel. Effects of the Invention

[0008] According to the power supply device for a railway vehicle according to the present disclosure, it is possible to achieve an effect that the power of the storage battery that supplies power to the auxiliary machine can be used as power for emergency running. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 1 is a diagram showing a configuration example of a railway vehicle system including a power supply device according to an embodiment. Figure 2 1 is a diagram showing a configuration example of a power supply main circuit which is a main circuit of the power supply device according to the embodiment. Figure 3 This is a block diagram showing an example of a hardware configuration for realizing the functions of a control unit in the embodiment. Figure 4 Detailed Description of the Invention It is a block diagram showing another example of the hardware configuration for realizing the functions of the control unit in the embodiment. Figure 5 It is a diagram showing a configuration of a power supply device according to Modification 1 of the embodiment. Figure 6 It is a diagram showing a configuration of a power supply device according to Modification 2 of the embodiment. Figure 7 It is a diagram showing a configuration of a power supply device according to Modification 3 of the embodiment. Figure 8 It is a diagram showing a configuration of a power supply device according to Modification 4 of the embodiment. DETAILED DESCRIPTION

[0010] Hereinafter, a power supply device for a railway vehicle according to an embodiment of the present disclosure (hereinafter, appropriately referred to as a "power supply device") will be described in detail with reference to the accompanying drawings. In the following description, the term "connection" includes both a case where components are directly connected to each other and a case where components are indirectly connected to each other via other components.

[0011] Implementation method. Figure 1 1 is a diagram showing a configuration example of a railway vehicle system 100 including a power supply device 5 according to an embodiment. The railway vehicle system 100 according to the embodiment includes a power collection device 2, a power conversion device 3, a main motor 4, a power supply device 5, a DC load 6, and a battery 9. These components are mounted on a railway vehicle 110. The main motor 4 is a propulsion motor that provides propulsion force to the railway vehicle 110.

[0012] The power collector 2 collects direct current from the overhead line 1. The power collector 2 supplies the collected direct current to the power conversion device 3. The power conversion device 3 converts the direct current supplied from the power collector 2 into alternating current for the main motor 4. As the power conversion device 3, a VVVF inverter is used which converts an applied direct current voltage into an alternating current voltage of a variable voltage (Variable Voltage) and a variable frequency (Variable Frequency).

[0013] The power collector 2 supplies the collected DC power to the power supply device 5. The power supply device 5 converts the DC power supplied from the power collector 2 into DC power for the DC load 6. The DC load 6 includes an auxiliary machine 8.

[0014] As described above, the auxiliary machine 8 is a load other than the propulsion motor among the loads mounted on the railway vehicle 110. Examples of the auxiliary machine 8 are interior lighting, door opening and closing devices, air conditioning devices, security equipment, compressors, batteries, and control power supplies. The battery 9 is a large-capacity power storage device. Figure 1 , and are shown separately from the auxiliary machine 8. Among the auxiliary machines 8, the in-vehicle lighting device, the door opening and closing device, the air conditioning device, the security equipment, the compressor, etc. are loads that are operated by receiving the supply of AC power, and the power supply to these loads is performed via a three-phase inverter not shown. In addition, among the auxiliary machines 8, a small-capacity battery, a control power supply, etc. are loads that are supplied with DC power, and the power supply to these loads is performed via a charger or a DC (Direct Current: Direct Current) / DC converter not shown.

[0015] The power supply device 5 involved in the embodiment is configured to use the power from the overhead line 1 to supply power to the auxiliary machine 8 during normal driving, and is configured to use the power from the battery 9 to supply power to the auxiliary machine 8 and the main motor 4 during emergency driving. Normal driving means driving when power is supplied from the overhead line 1, and emergency driving means driving when power is not supplied from the overhead line 1 due to, for example, a power outage.

[0016] During normal travel, power can be supplied from the overhead wire 1, and the auxiliary machine 8 is supplied with power using the power from the overhead wire 1. On the other hand, during emergency travel, the power supply from the overhead wire 1 is interrupted, so the auxiliary machine 8 is supplied with power stored in the battery 9, and the main motor 4 is driven using the power stored in the battery 9, thereby implementing emergency travel to the destination. In addition, in the event of a failure of the power conversion device 3 as the main conversion device, emergency travel based on the power supply device 5 can also be implemented. In the emergency travel in this case, the railway vehicle 110 that has been stopped in an emergency can be moved to a place that does not hinder the operation of other railway vehicles.

[0017] In addition, Figure 1 In the figure, an overhead wire is shown as the overhead wire 1, and a pantograph-shaped current collector is shown as the current collector 2, but the present invention is not limited thereto. The overhead wire 1 may be a third rail used in a subway, etc., and accordingly, the current collector 2 may be a third rail current collector. Figure 1 , the overhead line 1 is a DC overhead line, but the overhead line 1 may be an AC overhead line. In addition, when the overhead line 1 is an AC overhead line, a main transformer for stepping down the AC voltage received is provided at the rear stage of the power collector 2, and a converter for converting the AC voltage output from the main transformer into a DC voltage is provided at the rear stage of the main transformer.

[0018] Next, a specific circuit configuration of the power supply device 5 according to the embodiment will be described. Figure 2 FIG. 2 is a diagram showing a configuration example of a power supply main circuit 20 which is a main circuit of the power supply device 5 according to the embodiment. Figure 1 The same structural elements are indicated by the same reference numerals. Figure 2 As shown, the power supply main circuit 20 includes a chopper circuit 21, a capacitor C1, a resonant DC / DC converter 22, and a control unit 30. The resonant DC / DC converter 22 includes a first inverter 24, a resonant circuit 25, a transformer 28, and a second inverter 26.

[0019] The transformer 28 is an insulating transformer having a primary winding 28a and a secondary winding 28b magnetically coupled to each other. Herein, the side connected to the primary winding 28a is referred to as the "primary side", and the side connected to the secondary winding 28b is referred to as the "secondary side".

[0020] The chopper circuit 21 is arranged on the primary side of the transformer 28. The chopper circuit 21 includes a first reactor L1, a first switching element Q11, and a second switching element Q12.

[0021] The first inverter 24 is arranged between the chopper circuit 21 and the transformer 28 on the primary side of the transformer 28. The first inverter 24 includes four third to sixth switching elements Q21 to Q24 connected in a bridge manner. The connection point between the third switching element Q21 and the fifth switching element Q23 is led out to the outside to form a first DC terminal 24a, and the connection point between the fourth switching element Q22 and the sixth switching element Q24 is led out to the outside to form a second DC terminal 24b.

[0022] In the chopper circuit 21, one end of the first reactor L1 is connected to the first DC terminal 24a of the first inverter 24. One end of the first switching element Q11 is connected to the other end of the first reactor L1, and the other end is connected to the overhead line 1 side. One end of the second switching element Q12 is connected to the other end of the first reactor L1, and the other end is connected to the second DC terminal 24b of the first inverter.

[0023] The positive side of the capacitor C1 is connected to the first DC terminal 24a, and the negative side is connected to the second DC terminal 24b between the chopper circuit 21 and the first inverter 24. The capacitor C1 connected in this way is provided to smooth the DC voltage output from the chopper circuit 21 and the DC voltage output from the first inverter 24.

[0024] The resonant circuit 25 is arranged between the first inverter 24 and the transformer 28. The resonant circuit 25 has a resonant capacitor C2 and a second reactor L2. The resonant circuit 25 performs a series resonant operation using the capacitance component of the resonant capacitor C2 and the inductance component of the second reactor L2. That is, the second reactor L2 functions as an inductance component in the resonant circuit 25. In addition, the leakage inductance of the transformer 28 can be used instead of the second reactor L2. In this case, the second reactor L2 can be omitted.

[0025] The second inverter 26 is disposed between the transformer 28 and the DC load 6 on the secondary side of the transformer 28. The second inverter 26 includes four seventh to tenth switching elements Q31 to Q34 connected in a bridge manner.

[0026] An example of the first and second switching elements Q11, Q12, the third to sixth switching elements Q21 to Q24, and the seventh to tenth switching elements Q31 to Q34 is the illustrated MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), but may also be an IGBT (Insulated Gate Bipolar Transistor) or a transistor element other than the IGBT.

[0027] The first and second switching elements Q11, Q12, the third to sixth switching elements Q21 to Q24, and the seventh to tenth switching elements Q31 to Q34 each have a diode connected in reverse parallel. Reverse parallel means that the first terminal corresponding to the drain of the MOSFET is connected to the cathode of the diode, and the second terminal corresponding to the source of the MOSFET is connected to the anode of the diode.

[0028] In addition, as the first and second switching elements Q11, Q12, the third to sixth switching elements Q21 to Q24, and the seventh to tenth switching elements Q31 to Q34, Si-based semiconductors with silicon (Si: silicon) as the material are generally used as the mainstream, but wide bandgap semiconductors with silicon carbide (SiC: silicon carbide), gallium nitride (GaN), gallium oxide (Ga2O3), diamond, etc. can also be used. If each switching element is formed of a wide bandgap semiconductor material, low loss and high-speed switching can be achieved.

[0029] The control unit 30 generates a switching signal G11 for controlling the first and second switching elements Q11 and Q12 of the chopper circuit 21 based on a detection signal from a sensor not shown, and outputs the switching signal to the chopper circuit 21. In addition, the control unit 30 generates a switching signal G12 for controlling the third to sixth switching elements Q21 to Q24 of the first inverter 24 based on a detection signal from a sensor not shown, and outputs the switching signal to the second inverter 26. Furthermore, the control unit 30 generates a switching signal G13 for controlling the seventh to tenth switching elements Q31 to Q34 of the second inverter 26 based on a detection signal from a sensor not shown, and outputs the switching signal to the second inverter 26.

[0030] As described above, the power supply device 5 according to the embodiment is a power supply device for railway vehicles, which is mounted on the railway vehicle 110 equipped with the battery 9 and includes the transformer 28 having the primary winding 28a and the secondary winding 28b magnetically coupled to each other and insulating the primary side and the secondary side.

[0031] Next, the operation of the power supply device 5 according to the embodiment will be described. The chopper circuit 21 performs a step-down operation or a direct-through operation when power is supplied from the overhead wire 1, and performs a step-up operation when power is supplied from the battery 9. That is, the chopper circuit 21 performs a step-down operation or a direct-through operation during normal driving, and performs a step-up operation during emergency driving. The direct-through operation is an operation when the second switching element Q12 is always turned off, and the voltage of the overhead wire 1 is not stepped down, but is applied to the capacitor C1 via the first switching element Q11 and the first reactor L1.

[0032] In addition, in the step-down operation of the chopper circuit 21, the current flow path is ensured by the reverse parallel connected diode, so the second switch element Q12 does not need to be turned on. On the other hand, synchronous rectification can be performed to turn on the second switch element Q12 at the timing when the current flows through the reverse parallel connected diode. Since the voltage drop caused by the on-resistance of the transistor is smaller than the voltage drop in the forward direction of the diode, the loss in the chopper circuit 21 can be reduced by performing synchronous rectification.

[0033] The capacitor C1 smoothes and holds the DC voltage output from the chopper circuit 21. The capacitor C1 also smoothes and holds the DC voltage output from the first inverter 24.

[0034] The first inverter 24 converts the DC voltage applied from the chopper circuit 21 into an AC voltage and applies it to the primary side of the transformer 28, and converts the AC voltage applied from the primary side of the transformer 28 into a DC voltage and applies it to the chopper circuit 21. The first inverter 24 operates as an inverter circuit during normal driving and operates as a rectifier circuit during emergency driving.

[0035] During normal driving, the third to sixth switching elements Q21 to Q24 of the first inverter 24 operate in such a manner that their respective current rates become 50%. During this operation, two switching elements located diagonally to each other among the third to sixth switching elements Q21 to Q24, that is, the group of the third and sixth switching elements Q21, Q24, and the group of the fourth and fifth switching elements Q22, Q23, are simultaneously turned on or turned off. In addition, during switch control, it is self-evident that a dead time is set in order to prevent the deviation of the circuit operation from causing the switching elements of the group of the third and fourth switching elements Q21, Q22, and the group of the fifth and sixth switching elements Q23, Q24 connected in series to be simultaneously turned on. The current rate of 50% described here means the current rate for which the dead time is set.

[0036] As described above, in the resonance circuit 25, the capacitance component of the resonance capacitor C2 and the inductance component of the second reactor L2 are used to perform a series resonance operation. Through this series resonance operation, a resonance current flows through the resonance circuit 25. The third to sixth switching elements Q21 to Q24 are controlled so that their respective flow rates are 50%, so that the conduction operation of the group of the third and sixth switching elements Q21 and Q24 and the conduction operation of the fourth and fifth switching elements Q22 and Q23 can be switched using the zero point where the resonance current is zero. This operation is an example of a soft switching method and is called "zero current switching". As a result, the switching loss in the third to sixth switching elements Q21 to Q24 can be reduced, so that the operation of the first inverter 24 can be reduced in loss.

[0037] In addition, during emergency driving, the flow of power in the first inverter 24 is from the resonant current 25 to the chopper circuit 21, and the current flow path is ensured by the reverse parallel connected diodes, so the third to sixth switching elements Q21 to Q24 do not need to be turned on. On the other hand, synchronous rectification can be performed at the timing when the current flows through the reverse parallel connected diodes to turn on the corresponding switching elements. By performing synchronous rectification, the loss in the first inverter 24 can be reduced.

[0038] Furthermore, during emergency driving, the voltage applied to the capacitor C1 via the first inverter 24 is controlled by adjusting the voltage boost rate of the chopper circuit 21. Thus, even when the voltage of the capacitor C1 is adjusted to a desired voltage, the current rate of the third to sixth switching elements Q21 to Q24 can be maintained at 50%. Thus, even when the voltage of the capacitor C1 is adjusted to a desired voltage, the switching loss in the first inverter 24 can be reduced.

[0039] The second inverter 26 converts the AC voltage applied from the secondary side of the transformer 28 into a DC voltage and applies it to the DC load 6 and the battery 9 connected in parallel with the DC load 6, and converts the DC voltage applied from the battery 9 into an AC voltage and applies it to the secondary side of the transformer 28. The second inverter 26 operates as a rectifier circuit during normal driving and operates as an inverter circuit during emergency driving.

[0040] As described above, the power supply device 5 according to the embodiment is configured to use the power from the overhead wire 1 to supply power to the auxiliary machine 8 during normal travel, and to use the power from the battery 9 to supply power to the auxiliary machine 8 and the main motor 4 mounted on the railway vehicle 110 during emergency travel. Thus, the power supply device 5 according to the embodiment can use the power of the battery 9 supplied to the auxiliary machine 8 as power for emergency travel.

[0041] Figure 31 is a block diagram showing an example of a hardware structure for realizing the functions of the control unit 30 in the embodiment. Figure 3 As shown, a configuration including a processor 300 for performing calculations, a memory 302 for storing programs read by the processor 300, and an interface 304 for inputting and outputting signals can be adopted.

[0042] The processor 300 is an example of a computing unit. The processor 300 may be a computing unit called a microprocessor, a microcomputer, a microcontroller, a CPU (Central Processing Unit) or a DSP (Digital Signal Processor). In addition, the memory 302 may exemplify nonvolatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), EEPROM (registered trademark) (Electrically EPROM), and magnetic disks, floppy disks, optical disks, compact disks, mini disks, and DVDs (Digital Versatile Discs).

[0043] The memory 302 stores a program for executing the functions of the control unit 30 in the embodiment. The processor 300 can exchange necessary information via the interface 304, and the processor 300 executes the program stored in the memory 302 to perform the above-mentioned processing. The calculation results obtained by the processor 300 can be stored in the memory 302.

[0044] In addition, when realizing the function of the control unit 30 in the embodiment, it is possible to adopt Figure 4 The structure shown. Figure 4 It is a block diagram showing another example of the hardware configuration for realizing the function of the control unit 30 in the embodiment. Figure 4 middle, Figure 3The processor 300 and the memory 302 shown are replaced by a processing circuit 303. The processing circuit 303 is equivalent to a single circuit, a composite circuit, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Signals input to the processing circuit 303 and information output from the processing circuit 303 can be exchanged via an interface 304.

[0045] Next, a modification of the power supply device 5 according to the embodiment will be described. Figure 5 It is a diagram showing a configuration of a power supply device 5A according to Modification 1 of the embodiment. Figure 2 In the above description, the power supply device 5 has a structure having one power supply main circuit 20, but in Figure 5 In the power supply device 5A shown, two power supply main circuits 20 are connected in parallel to the overhead line 1 and the DC load 6. Figure 5 This is just an example, and the number of main power supply circuits 20 connected in parallel may be three or more.

[0046] Figure 5 In the structure of the power supply device 5A shown, an interleaved operation is applied to two power supply main circuits 20. The interleaved operation means that the phases are staggered in one cycle of processing. For example, when the number of power supply main circuits 20 is 2, the phases are staggered by 180 degrees, and when the number of power supply main circuits 20 is 4, the phases are staggered by 90 degrees. When the power supply main circuits 20 are interleaved, the ripple of the voltage in the circuit can be reduced, so the capacitance of the capacitor C1 can be reduced.

[0047] Figure 6 It is a diagram showing a configuration of a power supply device 5B according to a second modification of the embodiment. Figure 5 In the embodiment, the chopper circuit 21, the first inverter 24, the resonant circuit 25, the transformer 28 and the second inverter 26 in the power supply main circuit 20 are all connected in parallel. Figure 6 As shown, it is possible to configure the second inverter 26 in parallel. Even with such a configuration, interleaving operation can be performed, and the same effects as those of the power supply device 5A according to the first modification can be obtained.

[0048] also, Figure 7 It is a diagram showing a configuration of a power supply device 5C according to a third modification of the embodiment. Figure 6 In the embodiment, only the second inverter 26 is connected in parallel. Figure 7As shown, the chopper circuit 21, the first inverter 24, and the resonant circuit 25 except the second inverter 26 can be connected in parallel. Even in this configuration, interleaved operation can be performed, and the same effect as the power supply device 5A involved in the modification example 1 and the power supply device 5B involved in the modification example 2 can be obtained.

[0049] also, Figure 8 It is a diagram showing a configuration of a power supply device 5D according to a fourth modification of the embodiment. Figure 7 In the embodiment, the chopper circuit 21, the first inverter 24 and the resonant circuit 25 are connected in parallel. Figure 8 As shown, it is possible to configure only the parallel chopper circuit 21. Even with such a configuration, interleaving operation can be performed, and the same effects as those of the power supply device 5A according to the first modification, the power supply device 5B according to the second modification, and the power supply device 5C according to the third modification can be obtained.

[0050] As described above, the power supply device for railway vehicles involved in the embodiment is mounted on a railway vehicle equipped with a battery, and includes a transformer that insulates the primary side and the secondary side. The power supply device includes a chopper circuit arranged on the primary side of the transformer, a first inverter arranged between the chopper circuit and the transformer, a resonant circuit having a resonant capacitor and arranged between the first inverter and the transformer, and a second inverter arranged between the transformer and the DC load. The chopper circuit performs a step-down operation when power is supplied from the overhead line side, and performs a step-up operation when power is supplied from the battery side. The first inverter converts the DC voltage applied from the chopper circuit into an AC voltage and applies it to the primary side of the transformer, and converts the AC voltage applied from the primary side of the transformer into a DC voltage and applies it to the chopper circuit. The resonant circuit performs a series resonant operation through the capacitance component and the inductance component of the resonant capacitor. The second inverter converts the AC voltage applied from the secondary side of the transformer into a DC voltage and applies it to the DC load and the battery connected in parallel with the DC load, and converts the DC voltage applied from the battery into an AC voltage and applies it to the secondary side of the transformer. By means of the above-mentioned structural elements, the power supply device for railway vehicles is configured to use the power from the overhead wire to supply power to the auxiliary machine during normal travel, and to use the power from the storage battery to supply power to the auxiliary machine and the main motor mounted on the railway vehicle during emergency travel. Thus, a power supply device for railway vehicles can be obtained, which can utilize the power of the storage battery supplying power to the auxiliary machine as power for emergency travel.

[0051] In addition, in the above structure, the chopper circuit can be constructed to include: a first reactor having one end connected to the first DC terminal of the first inverter; a first switching element having one end connected to the other end of the first reactor and the other end connected to the overhead line; and a second switching element having one end connected to the other end of the first reactor and the other end connected to the second DC terminal of the first inverter, and including a diode connected in reverse parallel with the second switching element. In this structure, the second switching element can perform a synchronous rectification action when the chopper circuit performs a step-down action, and the synchronous rectification action is a conduction action performed at the timing when the current flows through the reverse parallel-connected diode. Thereby, the loss in the chopper circuit can be reduced.

[0052] In addition, in the above structure, the third to sixth switching elements of the first inverter can be operated in a manner that their respective current rates are 50%, and two switching elements located diagonally to each other can be operated in a manner that they are simultaneously turned on or off. Through this operation, the switching loss in the third to sixth switching elements can be reduced, and the operation of the first inverter can be reduced in loss.

[0053] In addition, in the above structure, a capacitor for smoothing the DC voltage output from the chopper circuit or the DC voltage output from the first inverter can be arranged between the chopper circuit and the first inverter. In this structure, the voltage applied to the capacitor via the first inverter is controlled by adjusting the voltage boost rate of the chopper circuit. Thus, even when the voltage of the capacitor C1 is adjusted to a desired voltage, the flow rate of the third to sixth switching elements Q21 to Q24 can be maintained at 50%, thereby reducing the switching loss in the first inverter 24.

[0054] The structures shown in the above embodiments are merely examples of the contents of the present invention, and may be combined with other known technologies, or a part of the structures may be omitted or modified within the scope not departing from the gist of the present invention. Description of symbols

[0055] 1 Overhead lines 2. Current collection device 3 Power conversion device 4 Main motor 5.5A, 5B, 5C, 5D power supply unit 6 DC load 8 Auxiliary Engines 9. Battery 20 Power supply main circuit 21 Chopper Circuit 22Resonant DC / DC Converter 241st inverter 24a 1st DC terminal 24b Second DC terminal 25 Resonance Circuit 26 2nd inverter 28 Transformer 28a Primary winding 28b Secondary winding 30 Control Department 100 Railway Vehicle Systems 110 Railway vehicles 300 processors 302 Memory 303 Processing Circuit 304 Interface C1 capacitor C2 Resonance capacitor G11~G13 switch signal L1 No. 1 Reactor L2 Second reactor Q11 1st switch element Q12 2nd switch element Q21 3rd switch element Q22 4th switch element Q23 5th switch element Q24 6th switch element Q31 7th switch element Q32 8th switch element Q33 9th switch element Q34 is the 10th switching element.

Claims

1. A power supply device for railway vehicles, A power supply device for a railway vehicle equipped with a battery, and equipped with a transformer for insulating a primary side and a secondary side, is characterized in that it includes: a chopper circuit, which is arranged on the primary side of the transformer and performs a voltage-reducing operation when power is supplied from the overhead line side and a voltage-reducing operation when power is supplied from the battery side; a first inverter disposed between the chopper circuit and the transformer, converting a DC voltage applied from the chopper circuit into an AC voltage and applying the voltage to the primary side of the transformer, and converting an AC voltage applied from the primary side of the transformer into a DC voltage and applying the voltage to the chopper circuit; a resonant circuit having a resonant capacitor, arranged between the first inverter and the transformer, and performing a series resonant operation using a capacitance component and an inductance component of the resonant capacitor; as well as a second inverter, which is arranged between the transformer and the DC load, converts the AC voltage applied from the secondary side of the transformer into a DC voltage and applies it to the DC load and the battery connected in parallel with the DC load, and converts the DC voltage applied from the battery into an AC voltage and applies it to the secondary side of the transformer, The system is designed to use the power from overhead lines to supply power to auxiliary machines during normal driving. The vehicle is configured to be able to supply power to the auxiliary machine and a main electric motor mounted on the railway vehicle using electric power from the battery during emergency travel.

2. The power supply device for a railway vehicle according to claim 1, characterized in that: The chopper circuit performs a voltage step-down operation or a direct-through operation during normal driving, and performs a voltage step-up operation during emergency driving.

3. The power supply device for railway vehicles according to claim 1 or 2, characterized in that: The chopper circuit comprises: a first reactor having one end connected to the first DC terminal of the first inverter; A first switching element having one end connected to the other end of the first reactor and the other end connected to the overhead line side; and a second switching element having one end connected to the other end of the first reactor and the other end connected to the second DC terminal of the first inverter, The first switching element and the second switching element each include a diode connected in reverse parallel. The second switching element is configured to be turned on at a timing when a current flows through the diode connected in reverse parallel when the chopper circuit performs a voltage step-down operation.

4. The power supply device for a railway vehicle according to claim 1 or 2, characterized in that: comprising a second reactor disposed between the first inverter and the transformer, The second reactor functions as the inductance component in the resonance circuit.

5. The power supply device for a railway vehicle according to any one of claims 1 to 4, characterized in that: The first inverter includes third to sixth switching elements connected in a bridge manner. The third to sixth switching elements each include a diode connected in reverse parallel. The first inverter operates as an inverter circuit during normal running, and operates as a rectifier circuit during emergency running.

6. The power supply device for railway vehicles according to claim 5, characterized in that: The third to sixth switching elements are operated so that their respective current ratios become 50%, and two switching elements located diagonally to each other are turned on or off simultaneously.

7. The power supply device for a railway vehicle according to claim 6, characterized in that: A capacitor is provided between the chopper circuit and the first inverter, and smoothes the DC voltage output from the chopper circuit or the first inverter. The voltage applied to the capacitor via the first inverter is controlled by adjusting a voltage boost rate of the chopper circuit.

8. The power supply device for a railway vehicle according to any one of claims 1 to 7, characterized in that: The second inverter includes seventh to tenth switching elements connected in a bridge manner. The seventh to tenth switching elements each include a diode connected in reverse parallel. The second inverter operates as a rectifier circuit during normal running, and operates as an inverter circuit during emergency running.

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