JP6240023B2 - Power converter and railway vehicle equipped with the same - Google Patents

Description

  The present invention relates to a power conversion device, and is particularly suitable for application to a power conversion device for a railway vehicle including an inverter device, a DC-DC conversion device, a power storage device, and an auxiliary power supply device.

  In recent years, inverter devices widely used in the industry convert DC power to AC power by controlling a variable voltage variable frequency (hereinafter referred to as VVVF) using a pulse width modulation (PWM) method. This method is widely used.

  For example, in the field of railway vehicles, the VVVF inverter device is used to drive the motor to accelerate the vehicle, and at the time of braking, the motor is operated as a generator to convert kinetic energy into electric energy, which is an overhead train line (hereinafter referred to as an overhead train line). The regenerative brake control for returning the overhead train line to the train line is widely used.

  In addition, by applying the power storage device, the regenerative power obtained by the regenerative brake is charged to store the power, and this stored power can be used for the acceleration power of the vehicle. Technologies that can be used for power for lighting to achieve further energy saving are being studied.

  For example, Patent Document 1 discloses a system that utilizes stored power as power of an auxiliary power supply device. In the system disclosed in Patent Literature 1, an auxiliary power supply device is connected in series to a regenerative power storage device, and the current ripple reduction reactor of the regenerative power storage device and the auxiliary power supply device is shared, and the regenerative power storage device It has a configuration for supplying DC power to the auxiliary power supply device via the power storage unit.

  By adopting such a configuration, compared with the case where the auxiliary power supply device and the regenerative power storage device are connected in parallel, the current ripple reducing reactor can be omitted, and further, power is supplied from the regenerative power storage device to the auxiliary power supply device. In this case, the switching operation of the rectifier for discharging from the regenerative power storage device becomes unnecessary, and the device can be miniaturized. In addition, since the input power supply of the auxiliary power supply device serves as a power storage unit, power can be supplied to the auxiliary power supply device as a stable input power supply. When a power failure occurs on a train line or when a rectifier (DC-DC conversion circuit) fails. Can also supply power to the auxiliary power supply.

Moreover, the power converter and the DC-DC converter circuits are generally comprised of a switching element using a semiconductor element for power. In power conversion by the PWM method, DC power is converted into AC power by switching of a switching element. Since harmonic distortion is generated at the time of this power conversion, harmonic distortion by the power converter (inverter circuit) is In addition to absorbing the harmonic distortion caused by the DC-DC converter circuit, the harmonic distortion caused by the reactor and the capacitor is absorbed by the filter circuit consisting of the reactor and the capacitor. It is preventing.

  The power converter described above inputs DC power from the DC train line through the current collector during powering to accelerate the vehicle, and supplies the power to the power converter (inverter circuit) via the reactor and the capacitor. The electric motor is driven by converting electric power into three-phase AC electric power, and the vehicle is accelerated.

  In addition, at the time of regenerative braking for decelerating the vehicle, the regenerative power generated from the electric motor is returned to the DC train line through the same route as that during powering, so that the regenerative power is used as powering power for other vehicles on the same line. On the other hand, at the time of the above-described regenerative braking, the regenerative power generated from the electric motor is absorbed by the power storage device, and the power can be effectively used as the power of the auxiliary power supply device. In particular, when the load on the DC train line is small and the regenerative power cannot be returned to the DC train line, the normal power converter (inverter circuit) throttles the regenerative current, that is, the regenerative power, and the brake is applied by the air brake (light load). In the regenerative operation), the regenerative power that cannot be returned to the DC train line is absorbed by the power storage device, so that the regenerative power during the light load regenerative operation can be effectively used.

  Patent Document 2 discloses that an auxiliary power supply device is provided on the output side of the stored power, and the DC-DC conversion circuit (buck-boost chopper), the power storage device, and the auxiliary power device are connected in parallel. In addition, the inverter and the DC-DC conversion circuit (step-up / step-down chopper) are connected as separate units on the DC output side of the inverter. Patent Document 2 discloses input / output characteristics of a power storage device connected to an auxiliary power supply device, and the input / output characteristics are constant with respect to the amount of power stored in the power storage device.

JP 2009-95079 A JP 2008-131834 A

  However, in the above-mentioned patent document, a filter circuit is required in the input unit on the side connected to the DC-DC conversion circuit and the DC train line for receiving the power storage device, and there is a problem that the device size of the entire system increases. there were. In addition, when the power of the power storage device is used as the power supply power of the auxiliary power supply device, the input / output characteristics of the power storage device are not characteristics that allow the regenerative power to be used effectively, and therefore the regenerative power cannot be used effectively. was there.

  The present invention has been made in consideration of the above points, and a power conversion device capable of effectively using regenerative power while reducing the size of the device when using the power of the auxiliary power supply device including the power storage device, and We intend to propose a railway vehicle equipped with it.

In order to solve such a problem, in the present invention, first power conversion means for receiving first DC power by a first pair of positive and negative wires and converting it to first AC power, and the first power conversion An electric motor connected to the AC side of the means and the first DC power are received by the first pair of positive and negative wires and converted to a second DC power having a voltage level different from the voltage level of the first DC power. And second power conversion means for outputting the second pair of positive and negative wires, a first capacitor connected between the first pair of positive and negative wires, and power storage means for storing the second DC power. A first reactor connected between the second power conversion means and the power storage means, and a first circuit breaker and a second circuit breaker connected in series with the power storage means, A resistor connected in parallel with the second circuit breaker, the power storage means and the first A third circuit breaker connected between the reactor, a third power conversion means for converting the power of the power storage means into a second AC power, and the third power conversion means and the power storage means. A second capacitor connected in parallel with the power storage means, a fourth circuit breaker connected between the power storage means and the second capacitor, and an alternating current of the third power conversion means An AC circuit connected to the side, the first to third power conversion means, and a control means for controlling the power storage device, the first power conversion means and the second power conversion means, The control means determines the charging operation condition of the power storage means based on the load size of the third power conversion means and the voltage of the first capacitor. A power conversion device is provided.

  According to this configuration, the wiring inductance between the first power conversion unit and the second power conversion unit is reduced, the resonance frequency determined by the wiring inductance and the capacitance of the first capacitor is increased, and the inverter circuit and the DC -It is possible to prevent the resonance phenomenon of the direct current part connected in parallel with the DC conversion circuit. Further, the number of devices can be reduced by sharing the reactor and the capacitor. Further, by mounting the inverter circuit and the DC-DC conversion circuit on the same cooler, the size can be reduced, and the apparatus of the entire system can be reduced in size.

  ADVANTAGE OF THE INVENTION According to this invention, when using the electric power of the auxiliary power supply device provided with the electrical storage apparatus, the optimal energy saving system can be implement | achieved by utilizing effectively regenerative power, reducing an apparatus in size.

It is a figure which shows the structural example of the main circuit of the power converter device which concerns on the 1st Embodiment of this invention. It is a figure which shows the apparatus structural example of the integrated unit concerning the embodiment. It is a figure which shows the charge operation start condition of the electrical storage apparatus concerning the embodiment. It is a figure which shows the injection | throwing-in sequence of the circuit breaker of the power converter device concerning the embodiment. It is a figure which shows the example of another structure of the main circuit of the power converter device concerning the embodiment. It is a figure which shows the example of another structure of the control apparatus of the power converter device concerning the embodiment. It is a figure which shows the charging / discharging characteristic concerning the embodiment. It is a figure which shows the structural example of the main circuit of the power converter device which concerns on the 2nd Embodiment of this invention. It is a figure which shows the structural example of the main circuit of the power converter device which concerns on the 3rd Embodiment of this invention. It is a figure which shows the example of a main circuit structure of the conventional power converter device.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
(1) First Embodiment (1-1) Outline of this Embodiment First, a conventional power conversion device will be described with reference to FIG. 10 includes a DC train line 111, a current collector 112, a main switch 113, a charging resistor 114, a switch 115, a DC link unit 116, an electric motor 117, a power converter (inverter circuit) 118, From the contactors 119a to 119c, the DC ripple reducing reactors 120a and 120c, the filter capacitors 121a to 121c, the auxiliary power supply device 123, the regenerative power storage device 124, the DC-DC conversion circuit 125, the reactor 126, the contactor 127, and the power storage device 128. Composed.

  In the circuit shown in FIG. 10, an auxiliary power supply device 123 is connected in series to a regenerative power storage device 124, and the current ripple reduction reactor 120 c of the regenerative power storage device 124 and the auxiliary power supply device 123 is shared. The DC power is supplied to the auxiliary power supply device 123 through the power storage unit 124.

  Thereby, compared with the case where the auxiliary power supply device 123 and the regenerative power storage device 124 are connected in parallel by the DC link unit 116, the current ripple reducing reactor can be omitted, and further, the power is supplied from the regenerative power storage device 124 to the auxiliary power supply device 123. In the case of supplying, there is an effect that the switching operation of the rectifier for discharging from the regenerative power storage device 124 becomes unnecessary, and the device can be miniaturized. Moreover, since the input power supply of the auxiliary power supply device 123 serves as a power storage unit, it is possible to supply power to the auxiliary power supply device 123 as a stable input power supply, and at the time of a train line power failure or a rectifier (DC-DC conversion circuit). Even when a failure occurs, power can be supplied to the auxiliary power supply.

  Here, the power conversion device (inverter circuit) 118 and the DC-DC conversion circuit 125 are generally composed of switching elements using power semiconductor elements. In power conversion by the PWM method, DC power is converted to AC power by switching of a switching element. Since harmonic distortion occurs during this power conversion, the harmonic distortion caused by the power conversion device (inverter circuit) 118 is absorbed by the filter circuit including the reactor and the capacitor, and the harmonic distortion caused by the DC-DC conversion circuit 125. Wave distortion is also absorbed by a filter circuit composed of a reactor and a capacitor, thereby preventing harmonic distortion from flowing into the DC train line.

  The power converter 118 inputs DC power from the DC train line 111 through the current collector 112 during powering to accelerate the vehicle, and supplies power to the power converter (inverter circuit) 118 via the reactor 120a and the capacitor 121a. The electric motor 117 is driven by converting DC power into three-phase AC power, and the vehicle is accelerated.

  In addition, at the time of regenerative braking to decelerate the vehicle, the regenerative power generated from the electric motor 117 is returned to the DC train line through the same route as that during the power running, so that the regenerative power is used as the power running power of other vehicles on the same track. It is done. Further, at the time of regenerative braking, the regenerative power generated from the electric motor 117 is absorbed by the power storage device 128 and the power can be effectively used as the power of the auxiliary power supply device 123.

  In a light load state where the load on the DC train line 111 is small and the regenerative power cannot be returned to the DC train line 111, the normal power converter (inverter circuit) 118 restricts the regenerative current, that is, the regenerative power, and the brake is applied by the air brake (light Load regenerative operation). By absorbing the regenerative power that cannot be returned to the DC train line 111 by the power storage device 128, the regenerative power during the light load regenerative operation can be used effectively.

  Further, as described above, an auxiliary power supply device is provided on the output side of the stored power, the DC-DC conversion circuit (buck-boost chopper), the power storage device, and the auxiliary power supply device are connected in parallel, and the inverter and the DC- There is also a power conversion device in which a DC conversion circuit (step-up / step-down chopper) is connected as a separate unit on the DC output side of an inverter. In this power conversion device, the input / output characteristics of the power storage device connected to the auxiliary power supply device are constant with respect to the amount of power stored in the power storage device.

  However, in the above-described power conversion device, a filter circuit is required in the input unit connected to the DC-DC conversion circuit and the DC train line for receiving the power storage device, and the device size of the entire system is increased. There was a problem. In addition, when the power of the power storage device is used as the power supply power of the auxiliary power supply device, the input / output characteristics of the power storage device are not characteristics that allow the regenerative power to be used effectively, and therefore the regenerative power cannot be used effectively. was there. That is, the above power converter has the following four problems.

  In the power conversion device of FIG. 10, a filter circuit is required in the input unit on the side connected to the DC-DC conversion circuit 125 or the DC train line 111 for charging the power storage device 128, and the device size of the entire system is increased. To do. In addition, since there are filter circuits at the input portions of the inverter circuit 118 and the DC-DC conversion circuit 125, a resonance phenomenon may occur between these filter circuits, and a large return current may flow.

  Further, when the inverter and the step-up / step-down chopper are connected as separate units, at least a capacitor is required at the input section of each unit in order to suppress fluctuations in the input voltage. Therefore, the first problem of the present embodiment is to achieve downsizing of the entire system.

  In addition, when the charging characteristics of the power storage device are low and there is no destination to return the regenerative power from the inverter, the regenerative power cannot be recovered sufficiently even though there is a margin in the amount of power storage, and the regenerative power is used effectively. Can not do it. In particular, when the vehicle is a train, the charging characteristics of the power storage device are not characteristics that can be rapidly charged when charging from a train line while the vehicle is stopped or coasting. The fact that the vehicle cannot be charged quickly while the vehicle is stopped or coasting cannot be fully charged within the limited stopping time or coasting time, and if the load of the auxiliary power supply is large, the result is a decrease in the amount of electricity stored. , Leading to a power outage of the auxiliary power supply.

  On the other hand, when there is a margin in the amount of power storage, positive charging is not necessarily the optimal operation for energy saving. For example, when the load of the auxiliary power supply device is small, the amount of discharge power from the auxiliary power supply device is small, so the power storage amount of the power storage device increases greatly with each regenerative operation, resulting in a large amount of power storage, and as a result Regenerative power cannot be absorbed.

  Therefore, the second problem of the present embodiment is to increase the energy saving effect by using the charging characteristics of the power storage device as the charging condition characteristics according to the load of the auxiliary power supply. Specifically, the charging condition of the power storage device used as a power source for the auxiliary power supply and for the effective use of the regenerative power is ensured by absorbing the regenerative power while ensuring the amount of power required for the auxiliary power supply. The system is designed to increase the energy saving effect of the system sufficiently.

  In addition, the capacitor connected in parallel to the input unit of the auxiliary power supply device usually has a large capacity, and at the moment when it is connected to the power storage device when the contactor is turned on, the voltage of the power storage device is applied to the capacitor, and the power storage unit And an excessive current flows between the capacitors. Therefore, a third problem of the present embodiment is to provide a circuit configuration that prevents this excessive current and a contactor charging sequence that corresponds to the circuit configuration.

  Further, in an emergency where the power storage device is opened due to a failure or the like and the power of the auxiliary power supply device is supplied from the train line, the DC-DC conversion circuit performs constant voltage control. Therefore, a fourth problem of the present embodiment is to safely convert power even in an emergency as a configuration in which the DC-DC conversion circuit follows the load fluctuation of the auxiliary power supply device when the power storage device fails. .

(1-2) Configuration of Power Converter The configuration of the main circuit of the power converter according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, the power conversion device includes a DC train line 1, a current collector 2, a reactor 3, an inverter circuit (indicated as INV in the figure) 5 and an integrated unit 21 of a DC-DC conversion circuit 6, an electric motor 17, an electric storage device. The device 10, the capacitor 8 connected in parallel with the power storage device 10, the reactor 7, the integrated unit 21 of the inverter circuit 5 and the DC-DC conversion circuit 6, the auxiliary power supply device 22, and the like.

  The integrated unit 21 includes a capacitor 4 and switching elements 18a and 18b for performing DC-DC conversion. The integrated power storage device 23 also includes circuit breakers 9a, 9b, 9c and 9d, and a resistor 19b.

  The auxiliary power supply (SIV) 22 includes a capacitor 11, an inverter circuit 12, an AC reactor 13, an AC capacitor 14, a transformer 15, and the like. A load 16 is connected to the auxiliary power supply device 22. The integrated control device 31 controls the inverter circuit 5, the DC-DC conversion circuit 6, the devices in the integrated power storage device 23 of the power storage device 10, the auxiliary power supply device 22, and the like.

  An operation example of the power conversion device shown in FIG. 1 will be described. First, the case where the vehicle decelerates by regenerative braking will be described.

  Regenerative power generated from the electric motor 17 by the regenerative brake is charged to the power storage device 10 from the inverter circuit 5 and the capacitor 4 through the DC-DC conversion circuit 6, the reactor 7, the capacitor 8, and the circuit breakers 9c, 9b, 9a. Electric power exceeding the charging characteristics of the power storage device 10 is output from the current collector 2 to the DC train line 1 via the inverter circuit 5, the capacitor 4, and the reactor 3. The electric power stored in the power storage device 10 is supplied to the auxiliary power supply device 22 through the circuit breakers 9a, 9b, 9d.

  The auxiliary power supply device 22 supplies power stored in the power storage device 10 to the auxiliary machine 16 via the capacitor 11, the inverter circuit 12, the AC reactor 13, the AC capacitor 14, and the transformer 15. The integrated control device 31 monitors the entire state, causes the inverter circuit 5 to perform a regenerative operation, causes the DC-DC conversion circuit 6 to perform a step-down chopper operation, controls charging of the power storage device 10, Each device is controlled, for example, the inverter circuit 12 is operated.

  When the amount of power stored from the power storage device 10 decreases, such as when the vehicle stops for a long time, the DC-DC conversion circuit 6 is connected from the DC train line 1 to the current collector 2, the reactor 3, and the capacitor 4. The step-down chopper is operated to charge the power storage device 10 to prevent the power storage amount of the power storage device 10 from decreasing.

  In the circuit configuration shown in FIG. 1, by configuring the inverter circuit 5 and the DC-DC conversion circuit 6 with the integrated unit 21, the wiring between the inverter circuit 5 and the DC-DC conversion circuit 6 can be shortened. In addition, the wiring inductance included in the wiring of the DC-DC conversion circuit 6 can be reduced. FIG. 2 shows a device configuration example of the integrated unit 21 for reducing the wiring inductance.

  FIG. 2 is a perspective view showing an example of a device configuration of a power converter represented by the DC-DC converter circuit 6 and the inverter circuit 5. FIG. 2 shows a capacitor 51, a switching element 52, and bus bars 53 and 54 of the power converter. Here, the capacitor 51 of FIG. 2 corresponds to the capacitor 4 of FIG. 1, and the switching element 52 of FIG. 2 corresponds to the switching elements 18a and 18b of FIG. FIG. 2 shows the configuration 21.

As shown in FIG. 2, the capacitor 51 and the switching element 52 are arranged closest to each other, connected by a bus bar through the shortest path, and further, the positive electrode bus bar 53 and the negative electrode bus bar 54 are secured to ensure insulation. It has a structure in which superimposed. With this configuration, the inductance of the switching circuit including the wiring inductance in FIG. 1 can be reduced to the same value as that of the inverter circuit.

  Compared to the case where the inverter circuit 5 and the DC-DC conversion circuit 6 are assembled in separate units and connected by electric wires, the wiring inductance between the inverter circuit 5 and the DC-DC conversion circuit 6 and switching elements are included. The inductance of the circuit can be reduced to tens to hundreds of parts compared to the case where the inverter circuit 5 and the DC-DC conversion circuit 6 are connected by an electric wire.

  Further, the resonance frequency due to the capacitor 4 and the wiring inductance can be set to a frequency higher than the operating frequency of the inverter circuit 5 and the DC-DC conversion circuit 6. For this reason, the inverter circuit 5 and the DC-DC conversion circuit 6 perform switching operation during regenerative braking as described above. The resonance frequency of the circuit is sufficiently high with respect to these switching operation frequencies, and the inverter circuit 5 and the DC-DC conversion circuit 6 -It is possible to prevent resonance of current and voltage of the direct current section to which the DC conversion circuit 6 is connected.

  Furthermore, by reducing the circuit inductance, the surge voltage at the time of switching of the switching elements 18a and 18b of the DC-DC conversion circuit 6 can be suppressed, and the power voltage circuit superposition of the surge voltage can be reduced. Further, the capacitor can be shared by reducing the wiring inductance between the inverter circuit 5 and the DC-DC conversion circuit 6. As a result of reducing the number of devices by sharing capacitors, it is possible to downsize the cooler and downsize the entire system.

  Further, the voltage of the capacitor 4 is input to the integrated control device 31 in order to determine the charging condition for the power storage device 10 according to the voltage of the capacitor 4 described later. As described above, the number of wires used for control can be reduced by sharing the capacitor by the integrated unit and the control device by the integrated control device 31, and improve the control performance by handling the capacitor voltage in an integrated manner. be able to.

  By the way, in this embodiment, as shown in FIG. 3, the charging operation condition of the DC-DC conversion circuit 6 is changed according to the size of the load of the auxiliary power supply device 22 and the amount of power stored in the power storage device 10. .

  If the required operating time of the power storage device 10 is constant, the amount of power stored in the power storage device 10 necessary for the operation of the auxiliary power supply device 22 varies depending on the load of the auxiliary power supply device 22. As shown in the second problem, in order to always charge the power storage device 10 with regenerative power, the amount of power stored in the power storage device 10 immediately increases when the load of the auxiliary power supply device 22 is small. In a state where the amount of stored electricity is high, regenerative power cannot be absorbed, and the effect of this configuration of absorbing regenerative power during light load regenerative operation cannot be fully utilized.

  For this reason, as shown in FIG. 3, when the load of the auxiliary power supply 22 is small, only when the voltage Ec of the capacitor 4 that starts the charging operation from the stage where the amount of stored electricity is low is set high and the light load regenerative operation starts. Recharging absorption effect during light load regenerative operation is enhanced by charging operation. Whether the light load state has been reached can be determined as a light load state by using the voltage detection value Ec of the capacitor 4 and when the voltage rises above a specified value.

  Further, when the load of the auxiliary power supply device 22 is large, it is necessary to increase the amount of power storage in order to ensure the necessary operation time of the power storage device 10. For this reason, the charging operation is enabled from a state where the voltage Ec is low to some extent except in a range where the amount of stored electricity is high.

  As described above, by performing the setting as shown in FIG. 3, it is possible to enhance the regenerative absorption effect during the light load regenerative operation while securing the amount of power necessary for the auxiliary power supply device 22. Here, when the amount of stored electricity is high, overcharging can be prevented by providing a configuration in which the charging current is reduced according to the amount of stored electricity. Further, the voltage Ec for starting the charging operation is set to a value lower than the voltage at which the inverter circuit 5 starts to reduce the regenerative current by light load regeneration.

  In addition, the magnitude | size of the load of the auxiliary power supply device 22 may calculate DC power from the input DC voltage and DC current of the auxiliary power supply device 22, or may calculate AC power from the output AC voltage and AC current. . Further, if the load factor of the auxiliary power supply device 22 can be predicted to some extent according to the vehicle occupancy rate and seasonal conditions without performing power calculation, the magnitude of the load of the auxiliary power supply device 22 is determined based on such information. Thus, a method of switching the set values in FIG.

Next, the operation of this embodiment against the third problem. Although this configuration performs the above-described operation in the normal operation, it is necessary to perform the initial charging operation of the capacitor 8 and the capacitor 11 as an initial operation sequence until the normal operation is started.

  The initial charging operation of the capacitors 8 and 11 is performed by turning on the circuit breakers 9a to 9d connected to the power storage device 10 using the power storage device 10 as a power source.

  In the case of the configuration shown in FIG. 1, the circuit breakers 9a to 9d are put in the following order. That is, after the circuit breaker 9a is turned on (on), the circuit breaker 9c is turned on (on), and after the charging voltage of the capacitor 8 is charged to about the voltage of the power storage device 10, the circuit breaker 9c is opened (off). . Then, the circuit breaker 9d is turned on (on), the charge voltage of the capacitor 11 is charged to about the voltage of the power storage device 10, the circuit breaker 9c is turned on (on), and the circuit breaker 9b is turned on (on). And

  FIG. 4 shows a sequence of making the circuit breakers 9a to 9d described above. Here, the order of inserting the circuit breakers 9c and 9d may be reversed. For example, after the circuit breaker 9a is turned on (on), the circuit breaker 9d is turned on (on), and after the charging voltage of the capacitor 8 is charged to about the voltage of the power storage device 10, the circuit breaker 9d is opened (off). . Then, the circuit breaker 9c is turned on (on), and after the charging voltage of the capacitor 11 is charged to about the voltage of the power storage device 10, the circuit breaker 9d is turned on (on), and the circuit breaker 9b is turned on (on). It is good.

  Thereby, the excessive current at the time of capacitor charge shown to the said 3rd subject can be prevented. The resistor 19b connected in parallel to the circuit breaker 9b is a current limiting resistor for suppressing an excessive current during initial charging of the capacitor. The current limiting resistor may be installed as shown in FIG. 8 described in a second embodiment to be described later, but in the case of the configuration shown in FIG. 1, the number of limiting resistors can be reduced.

  FIG. 5 shows an example of the main circuit configuration in another system of the present embodiment. 1 is different in that the lower arm of the DC-DC conversion circuit 6 is replaced by a diode 19 from the switching element.

  When the power storage device 10 is used only for power supply to the auxiliary power supply device 22, the DC-DC conversion circuit 6 only needs to perform the step-down chopper operation, and therefore the configuration of FIG. 5 is sufficient. With this configuration, the drive circuit (not shown) of the switching element 18b of the lower arm of the DC-DC conversion circuit 6 shown in FIG. 1 can be omitted, and the device can be further downsized.

  FIG. 6 shows a configuration example of a control device according to another method of the present embodiment. 1 differs from the integrated control device 31 in that a control device A32 that controls the integrated power storage device and a control device B33 that controls the auxiliary power supply device 22 are used.

  In the case of the configuration shown in FIG. 6, in order to perform the charging operation of the power storage device 10 under the conditions set in FIG. 3 described above, a signal of the load power information Ps of the auxiliary power supply device 22 is sent from the control device B33 to the control device A32. The configuration. When the control device is provided as a configuration in which the integrated power storage device and the auxiliary power supply device are separated, the configuration illustrated in FIG. 6 is used.

  FIG. 7 is a diagram showing the charge / discharge characteristics of the power storage device 10 of the present embodiment. When the stored power of the power storage device 10 is used only for power supply to the auxiliary power supply device 22, the charging characteristics are high input characteristics except for a region where the amount of stored power is high, as shown in the charging characteristics A of FIG. The regenerative power from the inverter circuit 5 can be recovered to the maximum extent. On the other hand, the discharge characteristic is made constant according to the load power of the load 16 except for a region where the charged amount is low.

  In addition, when the power storage amount of the power storage device 10 is greatly reduced, and the charging operation of the power storage device 10 is performed from the DC train line 1 other than during the regenerative operation, the input characteristics such as the charging characteristics B during the coasting of the vehicle, The inside is set to input characteristics such as charging characteristics C, and the maximum value of charging characteristics is changed depending on whether the vehicle is coasting or stopped.

  This is because when the vehicle is stopped, the current collecting point of the DC train line 1 does not change, and when the charging characteristics are high, a large current flows through the current collecting point for a long time and the DC train line 1 generates heat. This is to prevent this. In particular, when the DC train line 1 is a catenary frame type, the DC train line 1 may be melted.

  On the other hand, when the vehicle is coasting, the current collecting point of the DC train line 1 moves and changes. Therefore, even when a large current continues to flow as when the vehicle is stopped, the DC train line 1 is heated. There is no such thing as fusing. For this reason, the charging characteristic is set to be lower when the vehicle is stopped than when the vehicle is coasting.

  By setting the charging characteristics in this way, the DC train line 1 can be rapidly charged within a limited time while the vehicle is stopped or coasting without melting the DC train line 1, thereby reducing the charge amount of the power storage device. Can be prevented.

  Further, the DC-DC conversion circuit 6 opens the power storage device 10 with the circuit breakers 9 a and 9 b and supplies power from the DC train line 1 when the power storage device 10 fails. When the DC-DC conversion circuit 6 performs constant voltage control and supplies power to the auxiliary power supply device 22, the output voltage control response of the DC-DC conversion circuit 6 is output to the output of the auxiliary power supply device 22, that is, the inverter circuit 12. Set to be faster than the voltage control response. Thereby, the voltage control of the DC-DC conversion circuit 6 can be made to follow the load fluctuation of the auxiliary power supply device 22 and the power supply can be stably performed.

(1-3) Effect of this Embodiment According to the above embodiment, the inverter circuit 5 (an example of the first power conversion means of the present invention) and the DC-DC conversion circuit 6 (the second of the present invention) Between the inverter circuit 5 and the DC-DC conversion circuit, the wiring inductance between the wiring converter and the capacitor 4 (an example of the first capacitor of the present invention) increases. 6 can prevent the resonance phenomenon of the direct current part connected in parallel with 6. Moreover, the number of devices can be reduced by sharing the reactor 3 and the capacitor 4. Further, by mounting the inverter circuit 5 and the DC-DC conversion circuit 6 on the same cooler, the size can be reduced, and the apparatus of the entire system can be reduced in size.

  Furthermore, by adopting a configuration in which the inverter circuit 5, the DC-DC conversion circuit 6, and the power storage device 10 are controlled by an integrated control device 31 (an example of the control means of the present invention), a detection signal such as a voltage detection signal is transmitted. It can be handled in an integrated manner within the integrated control device 31. As a result, the number of control signal wires of each power conversion means can be reduced and the control performance can be improved.

  In addition, the capacitor 11 on the input side of the inverter circuit 12 (an example of the third power conversion means of the present invention) when the first to fourth circuit breakers (the circuit breakers 9a, 9b, 9c, and 9d) are turned on (of the present invention) (A third capacitor) or a capacitor 8 (an example of the second capacitor of the present invention) connected in parallel to the DC-DC conversion circuit 6 (second power conversion means) can prevent an excessive current during initial charging. .

  Further, by determining the charging condition of the power storage means according to the load size of the third power conversion means, that is, the auxiliary power supply device, and the first DC voltage, the amount of power required for the third power conversion means can be obtained. By ensuring that the regenerative power is absorbed by the power storage means only when necessary, the regenerative absorption effect at the time of light load regeneration can be further enhanced and a more optimal energy saving system can be obtained.

  In addition, by changing the charging characteristics according to the state of powering, coasting, stopping, and regeneration of the vehicle, it can be charged quickly without fusing the train line while the vehicle is stopped or coasting, reducing the amount of stored electricity Can be prevented.

  Furthermore, the DC-DC conversion circuit 6 (second power conversion means) sets the constant voltage control response when the power storage means is opened earlier than the control response of the third power conversion means, so that the inverter circuit 12 Even when the load of the (third power conversion means) changes, power can be stably supplied to the third power conversion means, that is, the auxiliary power supply.

(2) Second Embodiment Hereinafter, a configuration different from that of the first embodiment will be described, and description of the same configuration as that of the first embodiment will be omitted.

  FIG. 8 shows the power conversion device of the present embodiment. In FIG. 8, instead of the resistor 19b shown in FIG. 1 of the first embodiment, a resistor 19c is connected in parallel with the circuit breaker 9c, and a resistor 19d is connected in parallel with the circuit breaker 9d.

  In the case of the configuration shown in FIG. 8, the number of resistors is increased as compared with FIG. 1 of the first embodiment, but the charging order of the circuit breaker is changed, so that the charging of the capacitor is completed and the normal operation is started. You can speed up the time.

  That is, the order of turning on the circuit breakers according to the present embodiment is as follows. First, the circuit breakers 9a and 9b are turned on at the same time (on), and then the capacitors 8 and 11 are charged at the same time. When it becomes, it becomes the order of making the circuit breakers 9c and 9d to be turned on. As a result, it is possible to shorten the time from the completion of the charging of the capacitor until the transition to the normal operation. Since the circuit breakers 9a and 9b are simultaneously turned on and then the circuit breakers 9c and 9d are turned on simultaneously, the circuit breaker insertion sequence can be simplified as compared with the first embodiment.

(3) Third Embodiment Hereinafter, a configuration different from the first embodiment will be described, and description of the same configuration as the first embodiment will be omitted.

  FIG. 9 shows a power conversion apparatus according to the present embodiment. In FIG. 9, the capacitor 8 shown in FIG. 1 of the first embodiment is omitted.

  The capacitor 8 shown in FIG. 1 is intended to absorb the current switching ripple due to the switching operation by the DC-DC conversion circuit 6 and the reactor 7 and suppress the current ripple of the power storage device 10.

  In the present embodiment, the capacitor 11 is shared and absorbs the switching ripple of the current caused by the switching operation by the DC-DC conversion circuit 6 and the reactor 7. In this configuration, since the capacitor 8 can be omitted, the entire apparatus can be downsized as compared with the first embodiment, but the wiring inductance between the reactor 7 and the capacitor 11 needs to be set small. For this reason, when the wiring inductance between the reactor 7 and the capacitor 11 can be set small, the configuration of the present embodiment is desirable.

DESCRIPTION OF SYMBOLS 1,111 DC train line 2,112 Current collector 3, 7, 120a, 120c, 126 Reactor 4, 8, 11, 51, 121a, 121b, 121c Capacitor 5, 12 Inverter circuit 6, 125 DC-DC conversion circuit 9a, 9b, 9c, 9d Breaker 10, 128 Power storage device 13 AC reactor 14 AC capacitor 15 Transformer 16 Load 17, 117 Electric motor 18a, 18b, 52 Switching element 19b, 19c, 19d Resistance 21 Integrated inverter circuit and DC-DC conversion circuit Units 22, 123 Auxiliary power supply device 23 Integrated power storage device 31 Integrated control device 32 Control device A
33 Controller B
34 Control signal between control device and integrated power storage device 35 Control signal between control device and auxiliary power supply device 113, 115 Switch 114 Charging resistor 116 DC link 118 Power converter 119a, 119b, 119c, 122, 127 Contactor 124 Regenerative power storage device

Claims (8)

First power conversion means for receiving first DC power through a first pair of positive and negative wires and converting the first DC power into first AC power;
An electric motor connected to the AC side of the first power conversion means;
The first DC power is received by the first pair of positive and negative wires, converted into second DC power having a voltage level different from the voltage level of the first DC power, and output by the second pair of positive and negative wires. A second power conversion means;
A first capacitor connected between the first pair of positive and negative wires;
Power storage means for storing the second DC power;
A first reactor connected between the second power conversion means and the power storage means;
A first circuit breaker and a second circuit breaker connected in series with the power storage means;
A resistor connected in parallel with the second circuit breaker;
A third circuit breaker connected between the power storage means and the first reactor;
Third power conversion means for converting the power of the power storage means into second AC power;
A second capacitor connected in parallel with the power storage means between the third power conversion means and the power storage means;
A fourth circuit breaker connected between the power storage means and the second capacitor;
An AC circuit connected to the AC side of the third power conversion means;
Control means for controlling the first to third power conversion means and the power storage means ;
Have
The first power conversion means and the second power conversion means are integrally connected without the same unit ,
The power conversion device, wherein the control means determines a charging operation condition of the power storage means based on a load size of the third power conversion means and a voltage of the first capacitor . The charging sequence of the first circuit breaker to the fourth circuit breaker is as follows:
Turn on the first circuit breaker, then turn on the third or fourth circuit breaker, then open the third or fourth circuit breaker, then turn on the fourth or third circuit breaker Then, the power conversion device according to claim 1 , wherein the third or fourth circuit breaker is inserted next . Instead of having a resistor in parallel with the second circuit breaker,
Characterized by a structure having a parallel resistor and the third circuit breaker and the fourth circuit breakers, power converter according to claim 1 or 2. The power converter according to any one of claims 1 to 3 , further comprising a third capacitor between the second pair of positive and negative wires on the output side of the second power conversion means. The second power conversion means, and performs only the step-down operation, power converter according to any one of claims 1-4. The power conversion device according to any one of claims 1 to 5 , wherein the charging characteristic of the power storage means is switched while the vehicle is coasting and stopped . The second power conversion means performs constant voltage control when the power storage means is opened, and supplies power to the third power conversion means. When the second power conversion means supplies power to the third power conversion means, and setting earlier than the control response of the means, the power conversion device according to any one of claims 1-6. A railway vehicle comprising the power conversion device according to any one of claims 1 to 7 .

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