Propulsion control apparatus of engine hybrid railroad vehicle

A first power converter connected to a plurality of motors is configured to operate as a DC/AC converter or an AC/DC converter. A second power converter connected to a generator is configured to operate as a DC/AC converter or the AC/DC converter. A control device is configured to cause the first power converter to supply alternating-current power from the first power converter to at least one motor among the motors and cause the second power converter to supply alternating-current power from the second power converter to a motor other than the motor to which the alternating-current power from the first power converter is supplied.

FIELD

The present invention relates to a propulsion control apparatus of an engine hybrid railroad vehicle.

BACKGROUND

A propulsion control apparatus of an engine hybrid railroad vehicle drives a generator with an engine, converts alternating-current power generated by the generator into direct-current power with a converter, converts the direct-current power from the converter and direct-current power from a power storage device into alternating-current power with an inverter, and drives a motor with the alternating-current power to thereby give propulsion to the vehicle (e.g., Patent Literature 1).

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

However, in the conventional technology represented by the above Patent Literature 1, a plurality of motors mounted on a vehicle are configured to be driven by one power converter. Therefore, for example, when power running is performed with stored power of a power storage device, the motors are simultaneously controlled. Therefore, in the conventional technology, there is a problem in that further improvement of efficiency of a railroad vehicle cannot be attained because, even when a sufficient driving force is obtained only by one motor, the other motor is also driven.

The present invention has been devised in view of the above and it is an object of the present invention to obtain a propulsion control apparatus of an engine hybrid railroad vehicle that can attain further improvement of efficiency of a railroad vehicle even in a configuration in which a plurality of motors are driven by one power conversion device.

Solution to Problem

In order to solve the aforementioned problems, a propulsion control apparatus of an engine hybrid railroad vehicle is constructed in such a manner that it includes: a generator driven by an engine; a power storage device functioning as a direct-current-power supply source configured to be connectable to a direct-current common section; first and second power converters each of which is configured to be connectable to the direct-current common section, when direct-current power from the direct-current common section is input from a first input/output end side, operates as a DC/AC converter to output desired alternating-current power from a second input/output end side different from the first input/output end, and, when alternating-current power is input from the second input/output end side, operates as an AC/DC converter to output desired direct-current power from the first input/output end side; a plurality of motors divided into a first motor configured to be drivable by both of the first and second power converters and a second motor configured to be drivable only by the first power converter; a group of switches that switches an electric connection destination of the generator from the second input/output end side of the second power converter to the second input/output end side of the first power converter or switches an electric connection destination of the first motor from the second input/output end side of the first power converter to the second input/output end side of the second power converter; and a control unit that controls operations of the first power converter, the second power converter, and the group of switches according to operation forms of the first and second power converters.

Advantageous Effects of Invention

According to the present invention, connection states between a plurality of motors and a first power converter and a second power converter are controlled by a control device, whereby one motor is driven by the first power converter and the other motor is driven by the second power converter. Therefore, there is an effect that it is possible to attain further improvement of efficiency of a railroad vehicle even in a configuration in which a plurality of motors are driven by one power conversion device.

DESCRIPTION OF EMBODIMENTS

Propulsion control apparatuses of an engine hybrid railroad vehicle (hereinafter simply referred to as “propulsion control apparatuses”) according to embodiments of the present invention are explained below with reference to the accompanying drawings. Note that the present invention is not limited by the embodiments explained below.

First Embodiment

FIG. 1is a configuration diagram of a propulsion control apparatus according to a first embodiment of the present invention. The propulsion control apparatus according to the first embodiment is configured by including, as main components, a first motor4, a second motor4A, a diesel engine7, a generator5, a first power converter1, a second power converter2, a power storage device9, and a control device100that controls the operation of the entire propulsion control apparatus.

The propulsion control apparatus is configured by including a high-speed breaker10, a first line breaker11, a second line breaker12, a third line breaker13, a fourth line breaker14, a first contactor71, a second contactor72, a third contactor73, a fourth contactor74, a fifth contactor75, and a sixth contactor76interposed among the main components to freely change a supply path of electric power. A first charging resistor30is connected to the second line breaker12in parallel. A second charging resistor31is connected to the fourth line breaker14in parallel.

Note that the propulsion control apparatus includes, in addition to these components, a first current detector60, a second current detector61, a third current detector63, a fourth current detector80, and a fifth current detector81. Further, the propulsion control apparatus includes a first voltage detector50, a second voltage detector51, a third voltage detector53, and a fourth voltage detector54that detect voltages.

Connection relations and schematic functions of the sections configuring the propulsion control apparatus are explained. The diesel engine7is connected to the generator5, which is one of power supply sources that generate electric power. The generator5is an alternating-current generator driven by the diesel engine7. That is, the diesel engine7and the generator5function as an alternating-current power supply source. The generator5is connected to the first power converter1via the first contactor71, the fourth contactor74, and the fifth contactor75and connected to the second power converter2via the third contactor73and the fourth contactor74. The generator5is supplied with alternating-current power by the second power converter2and operates as an alternating-current electric motor as well.

The power storage device9is a storage device for electric energy including a lithium ion battery, a nickel hydrogen battery, an electric double layer capacitor, a lithium ion capacitor, a flywheel, or the like as storage means. The power storage device9is connected to, as another power supply source that generates electric power, the first power converter1via the high-speed breaker10, the first line breaker11, and the second line breaker12and charges and discharges direct-current power. Further, the power storage device9is connected to the second power converter2via the high-speed breaker10, the third line breaker13, and the fourth line breaker14and charges and discharges direct-current power.

The first power converter1operates as an AC/DC converter or a DC/AC converter. When the first power converter1operates as an AC/DC converter, regenerative electric power from the first motor4, regenerative electric power from the second motor4A, or alternating-current power generated by the generator5is supplied to a second input/output end A2side located on the first motor4side of the first power converter1. In the first power converter1, the regenerative electric power and the alternating-current power are converted into direct-current power, and thus the direct-current power is charged to the power storage device9.

When the first power converter1operates as a DC/AC converter, direct-current power from the power storage device9or direct-current power from the second power converter2is supplied to a first input/output end A1side located on a direct-current common section20side of the first power converter1. In the first power converter1, these kinds of direct-current power are converted into alternating-current power. The alternating-current power is supplied to at least one of the first motor4and the second motor4A. The first motor4and the second motor4A are driven by this alternating-current power. Note that a rotating shaft of the first motor4and a rotating shaft of the second motor4A are respectively connected to reduction gears (not shown in the figure). The rotating shafts rotate, whereby wheels rotate via axles provided in the reduction gears and the vehicle travels.

The second power converter2operates as an AC/DC converter or a DC/AC converter. When the second power converter2operates as an AC/DC converter, alternating-current power generated by the generator5is supplied to a second input/output end B2side located on the generator5side of the second power converter2. In the second power converter2, the alternating-current power is converted into direct-current power. The direct-current power is charged to the power storage device9.

When the second power converter2operates as a DC/AC converter, regenerative electric power from the first motor4or direct-current power from the power storage device9is supplied to a first input/output end B1side located on the direct-current common section20side of the second power converter2. In the first power converter1, the direct-current power is converted into alternating-current power, and thus the alternating-current power is supplied to the first motor4or the generator5. The first motor4or the generator5is driven by the alternating-current power.

The first motor4receives the supply of the alternating-current power from the first power converter1or the alternating-current power from the second power converter2and generates a driving force (propulsion). The second motor4A receives the supply of the alternating-current power from the first power converter1and generates a driving force.

The high-speed breaker10is inserted between the direct-current common section20and the power storage device9. The first line breaker11and the second line breaker12are connected in series and inserted between the direct-current common section20and the first power converter1. The third line breaker13and the fourth line breaker14are connected in series and inserted between the direct-current common section20and the second power converter2. The sixth contactor76is inserted between the first power converter1and the second motor4A. The first contactor71and the second contactor72are connected in series and inserted between the first power converter1and the first motor4. The third contactor73and the fourth contactor74are connected in series and inserted between the second power converter2and the generator5.

One end of the first contactor71and one end of the second contactor72are connected to each other. One end of the third contactor73and one end of the fourth contactor74are connected to each other. The fifth contactor75is inserted between a connection end of the first contactor71and the second contactor72, and a connection end of the third contactor73and the fourth contactor74.

Next, the sensors are explained. The third voltage detector53detects a voltage EB of the power storage device9. The third current detector63detects a direct current IB flowing into and out of the power storage device9. The fourth voltage detector54detects a voltage ES of the direct-current common section20. The first voltage detector50detects a voltage EFC1of a first filter capacitor40. The first current detector60detects a direct current IS1flowing into and out of the first power converter1. The fourth current detector80detects an alternating current IM1flowing into and out of the first power converter1. Similarly, the second voltage detector51detects a voltage EFC2of a second filter capacitor41. The second current detector61detects a direct current IS2flowing into and out of the second power converter2. The fifth current detector81detects an alternating current IM2flowing into and out of the second power converter2.

A first speed detector90detects rotating speed (motor rotating speed) PG1of the first motor4. A second speed detector91detects rotating speed (generator rotating speed) PG2of the generator5. A third speed detector93detects rotting speed (motor rotating speed) PG3of the second motor4A.

The detection values detected by the sensors are input to the control device100as shown in the figure. An operation command from a not-shown motorman's platform is also input to the control device100. The control device100switches an operation mode of the vehicle according to the operation command and generates, on the basis of the detection values input from the various sensors, signals (PWM1and PWM2) for controlling not-shown switching elements of each of the power converters, a signal (HB) for controlling ON/OFF of the high-speed breaker10, signals (LB11to22) for controlling ON/OFF of the line breakers, and signals (LS11to22) for controlling ON/OFF of the contactors and outputs the signals to the control target sections. Answerbacks are input to the control device100from those devices.

Note that, inFIG. 1, illustration of control signals for the breaker, the line breakers, and the contactors is omitted to avoid complication. InFIG. 1, the diesel engine7, the generator5, the first motor4, the second motor4A, and the power storage device9are respectively represented as “ENG1” “G1”, “M1”, “M2”, and “BAT”. The first power converter1and the second power converter2are represented focusing on functions thereof. For example, when the first power converter1operates as an AC/DC converter, the first power converter1is represented as “CNV1”. When the first power converter1operates as a DC/AC converter, the first power converter1is represented as “INV1”. Similarly, when the second power converter2operates as an AC/DC converter, the second power converter2is represented as “CNV2”. When the second power converter2operates as a DC/AC converter, the second power converter2is represented as “INV2”.

Operations in respective modes in the propulsion control apparatus according to the first embodiment are explained.FIG. 2is a diagram of states of the devices during the departure of the vehicle. When an operation command indicating departure is input to the control device100, to reduce noise of the diesel engine7, the control device100does not use the generator5, but causes the first power converter1to perform an inverter operation to convert direct-current power from the power storage device9into alternating-current power, and drives the first motor4and the second motor4A.

More specifically, when confirming that the voltage EB of the power storage device9is a voltage in a normal range, the control device100turns on the high-speed breaker10. When confirming that the voltage ES of the direct-current common section20is a voltage in a normal range, the control device100turns on the first line breaker11. The first filter capacitor40is charged while an electric current is limited by the first charging resistor30. When detecting with the first voltage detector50that the first filter capacitor40has been charged to a predetermined voltage, the control device100turns on the second line breaker12and short-circuits the first charging resistor30. The control device100confirms that the fifth contactor75is off and turns on the sixth contactor76, turns on the first contactor71, turns on the second contactor72, turns off the third contactor73, and turns off the fourth contactor74. In this case, the control device100causes the first power converter1to operate as a DC/AC converter (INV1).

In the first power converter1, direct-current power from the power storage device9is converted into alternating-current power. The first motor4and the second motor4A are driven by the alternating-current power and the vehicle travels. Note that the other devices are set to an OFF state. According to this operation, the first motor4and the second motor4A are driven using stored power of the power storage device9. Therefore, it is possible to reduce the noise of the diesel engine7.

FIG. 3is a diagram of an operation in starting the diesel engine7using the stored power of the power storage device9. When the hybrid railroad vehicle reaches predetermined speed (or a predetermined travel distance, a predetermined elapsed time, or it can be an operation of a motorman, or a command from a railroad system), the control device100turns on the third line breaker13and charges the second filter capacitor41while limiting an electric current with the second charging resistor31. When confirming with the voltage EFC2detected by the second voltage detector51that the second filter capacitor41has been charged to a predetermined voltage, the control device100turns on the fourth line breaker14and short-circuits the second charging resistor31. The control device100confirms that the fifth contactor75is off and turns on the third contactor73and turns on the fourth contactor74. The control device100causes the second power converter2to operate as a DC/AC converter (INV2).

In the second power converter2, direct-current power from the power storage device9is converted into alternating-current power. The generator5is caused to operate as a motor by the alternating-current power to start the diesel engine7.

FIG. 4is a diagram of an operation in driving the motors using generated power of the generator5and the stored power of the power storage device9. When the diesel engine7is started by the operation shown inFIG. 3, after once stopping the inverter operation of the second power converter2, the control device100causes the second power converter2to restart as an AC/DC converter (CNV2). The control device100causes the first power converter1to operate as a DC/AC converter (INV1).

In the first power converter1, direct-current power from the power storage device9and the second power converter2is converted into alternating-current power. The first motor4and the second motor4A are driven by the alternating-current power and the vehicle accelerates.

FIG. 5is a diagram of states of the devices during coasting. When a power running command from the motorman's platform is turned off, the control device100stops the inverter operation of the first power converter1and turns off the first line breaker11and turns off the second line breaker12. In this case, when a state of charge (SOC) of the power storage device9is low, the power generation of the generator5driven by the diesel engine7is continued. The generated power is converted into direct-current power and charged to the power storage device9by the second power converter2. Note that a value of the SOC of the power storage device9is calculated from information from a not-shown battery monitoring device, the voltage EB and the electric current IB of the power storage device9, and the like.

FIG. 6is a diagram of states of the devices during braking. During the braking, the control device100causes the first motor4and the second motor4A to operate as generators. Regenerative electric power from the motors is input to the first power converter1. The control device100causes the first power converter1to operate as an AC/DC converter (CNV1). In the first power converter1, the regenerative electric power from the first motor4and the second motor4A is converted into direct-current power (regenerative brake). The direct-current power is charged to the power storage device9.

In this case, if the SOC of the power storage device9is lower than the predetermined value when the power storage device9is charged only by the regenerative electric power, the control device100drives the diesel engine7. The generated power from the generator5is input to the second power converter2. The control device100causes the second power converter2to operate as an AC/DC converter (CNV2). In the second power converter2, the generated power from the generator5is converted into direct-current power. The direct-current power is charged to the power storage device9.

On the other hand, if the SOC of the power storage device9is higher than the predetermined value or if the power storage device9cannot be charged, the control device100causes the second power converter2to operate as a DC/AC converter (INV2). Direct-current power from the first power converter1is input to the second power converter2via the direct-current common section20. The second power converter2converts the direct current power into alternating-current power and causes the generator5to operate as a motor. Therefore, the diesel engine7operates as an engine brake (further as an exhaust brake) and electric power is consumed. Note that, inFIG. 6, to simplify explanation, a state in the case in which the SOC of the power storage device9is higher than the predetermined value is shown.

According to the operation shown inFIG. 6, it is possible to continue the regenerative brake and suppress wear of brake shoes. Therefore, it is possible to suppress odor involved in the wear of the brake shoes. The life of the brake shoes is extended and a replacement cycle of the brake shoes is extended. It is possible to reduce costs.

FIG. 7is a diagram of states of the devices during the stopped state of the vehicle. When the vehicle is in a stopped state, for example, if power consumption in the vehicle (lighting, air conditioning, etc.) by not-shown auxiliary power supply devices is large or if the SOC of the power storage device9is lower than a predetermined value, the control device100drives the diesel engine7, and the generated power from the generator5is input to the second power converter2. The control device100causes the second power converter2to operate as an AC/DC converter (CNV2). In the second power converter2, the generated power from the generator5is converted into direct-current power. The direct-current power is charged to the power storage device9.

Note that, when the SOC of the power storage device9is high or when the power consumption in the vehicle by the not-shown auxiliary power supply devices is small, the control device100stops the diesel engine7. Consequently, it is possible to reduce noise and suppress fuel consumption of the diesel engine7.

FIG. 8is a diagram of states of the devices in the case of a breakdown of the first power converter1. When detecting a breakdown of the first power converter1, first, the control device100turns off the first line breaker11, the second line breaker12, the first contactor71, and the sixth contactor76. Consequently, the first input/output end A1of the first power converter1is disconnected from the power storage device9, and the second input/output end A2of the first power converter1is disconnected from the first motor4and the second motor4A.

Subsequently, the control device100stops the converter operation of the second power converter2and further turns off the fourth contactor74. Consequently, the second input/output end B2of the second power converter2is disconnected from the generator5.

Thereafter, if the SOC of the power storage device9is higher than the predetermined value, the control device100turns on the fifth contactor75and causes the second power converter2to operate as a DC/AC converter (INV2). The second power converter2converts direct-current power from the power storage device9into alternating-current power and drives the first motor4. Note that, inFIG. 8, to simplify explanation, a state in the case in which the SOC of the power storage device9is higher than the predetermined value is shown.

On the other hand, if the SOC of the power storage device9is lower than the predetermined value, the control device100stops the inverter operation of the second power converter2. The control device100turns off the fifth contactor75and turns on the fourth contactor74. Consequently, the second input/output end B2of the second power converter2is disconnected from the first motor4. Thereafter, the control device100causes the second power converter2to operate as an AC/DC converter (CNV2). The second power converter2converts the generated power from the generator5into direct-current power and charges the power storage device9.

The inverter operation and the converter operation by the second power converter2are repeated, whereby, even when the first power converter1is broken down, the vehicle can shelter in the nearest station or the like without being stranded on the mainline and disturbing a schedule. Further, it is made possible to drive the diesel engine7and cause the vehicle to travel until the volume of gas oil in a fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit.

FIG. 9is a diagram of states of the devices in the case of a breakdown of the second power converter2. When detecting a breakdown of the second power converter2, as shown inFIG. 9, the control device100turns off the third line breaker13, the fourth line breaker14, and the third contactor73. Consequently, the first input/output end B1of the second power converter2is disconnected from the power storage device9, and the second input/output end B2of the second power converter2is disconnected from the generator5.

In this case, if the SOC of the power storage device9is higher than the predetermined value, the control device100turns off the fifth contactor75and causes the first power converter1to operate as a DC/AC converter (INV1) to drive the first motor4and the second motor4A using the stored power of the power storage device9.

On the other hand, if the SOC of the power storage device9is lower than the predetermined value, the control device100stops the inverter operation of the first power converter1and further turns off the second contactor72and the sixth contactor76. Consequently, the second input/output end A2of the first power converter1is disconnected from the first motor4and the second motor4A. Thereafter, the control device100turns on the fifth contactor75and causes the first power converter1to operate as an AC/DC converter (CNV1). In the first power converter1, the generated power of the generator5is converted into direct-current power. The direct-current power is charged to the power storage device9.

The inverter operation and the converter operation by the first power converter1are repeated, whereby, even when the second power converter2is broken down, the vehicle can shelter in the nearest station or the like without being stranded on the mainline and disturbing a schedule. Further, it is possible to drive the diesel engine7and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit.

Note that, in the first embodiment, an example is explained in which the two motors are controlled by the first power converter1as shown in, for example,FIG. 2. However, the propulsion control apparatus can be configured such that one motor is controlled by the first power converter1and the other motor is controlled by the second power converter2. For example, according to a load of the vehicle or a route condition, the control device100turns on the sixth contactor76, turns off the first contactor71, turns on the second contactor72, turns on the third contactor73, turns off the fourth contactor74, turns on the fifth contactor75, causes the first power converter1to operate as a DC/AC converter (INV1), and causes the second power converter2to operate as a DC/AC converter (INV2). Therefore, the second motor4A is controlled by the first power converter1. The first motor4is controlled by the second power converter2. According to this operation, compared with when a plurality of motors are driven by one power conversion device, because the motors can be individually controlled, it is possible to attain improvement of vehicle performance.

In the first embodiment, one first motor4and one second motor4A are used. However, the number of the first motors4and the number of the second motors4A are not limited to this. Each of the first motor4and the second motor4A can be a plurality of motors. Further only one motor can be two or more motors. Note that, when two or more first power converters1are used, the first contactors71and the second contactors72are provided respectively between the first power converters1and the first motors4. A plurality of the fifth contactors75are provided to correspond to the first motors4.

As explained above, the propulsion control apparatus according to the first embodiment is configured to include the generator5driven by the diesel engine7, the power storage device9functioning as a direct-current power supply source configured to be connectable to the direct-current common section20, the first and second power converters1and2each of which is configured to be connectable to the direct-current common section20, when direct-current power from the direct-current common section20is input from the first input/output end A1side, operates as a DC/AC converter to output desired alternating-current power from the second input/output end sides A2and B2different from the first input/output ends A1and B1, and, when alternating-current power is input from the second input/output ends A1and B2sides, operates as an AC/DC converter to output desired direct-current power from the first input/output ends A1and B1sides, the motors divided into the first motor4configured to be drivable by both of the first and second power converters and the second motor4A configured to be drivable only by the first power converter1, the group of switches (71,72,73,74, and75) that switches an electric connection destination of the generator5from the second input/output end2B side of the second power converter2to the second input/output end A2side of the first power converter1or switches an electric connection destination of the first motor4from the second input/output end A2side of the first power converter1to the second input/output end B2side of the second power converter2, and the control unit (the control device100) that controls, according to operation forms of the first and second power converters1and2, the operations of the first power converter1, the second power converter2, and the group of switches. With this configuration, connection states of the motors and the first power converter1and the second power converter2are controlled. One motor is driven by the first power converter1and the other motor is driven by the second power converter2. As a result, it is made possible to attain further improvement of efficiency of the railroad vehicle even in a configuration in which the motors (4and4A) are controlled by one power conversion device (1). Further, compared with when a plurality of motors are driven by one power conversion device, because the motors can be individually controlled, it is possible to attain improvement of vehicle performance.

The control device100according to the first embodiment is configured to, when the first power converter1is broken down, if the SOC of the power storage device9is lower than the predetermined value, cause the second power converter2to operate as a DC/AC converter and supply alternating-current power from the second power converter2to the generator5and, after the diesel engine7starts, cause the second power converter2to operate as an AC/DC converter and supply direct-current power from the second power converter2to the power storage device9, and, if the SOC of the power storage device9is higher than the predetermined value, cause the second power converter2to operate as a DC/AC converter and supply alternating-current power from the second power converter2to the first motor4. Therefore, the inverter operation and the converter operation by the second power converter2are repeated. Even when the first power converter1is broken down, the vehicle can shelter in the nearest station or the like without being stranded on the mainline and disturbing a schedule. Further, it is made possible to drive the diesel engine7and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit.

The control device100according to the first embodiment is configured to, when the second power converter2is broken down, if the SOC of the power storage device9is lower than the predetermined value, cause the first power converter1to operate as a DC/AC converter and supply alternating-current power from the first power converter1to the generator5and, after the diesel engine7starts, cause the first power converter1to operate as an AC/DC converter and supply direct-current power from the first power converter1to the power storage device9, and, if the SOC of the power storage device9is higher than the predetermined value, cause the first power converter1to operate as a DC/AC converter and supply alternating-current power from the first power converter1to the first motor4. Therefore, the inverter operation and the converter operation by the first power converter1are repeated. Even when the second power converter2is broken down, the vehicle can shelter in the nearest station or the like without being stranded on the mainline and disturbing a schedule. Further, it is made possible to drive the diesel engine7and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit.

Second Embodiment

FIG. 10is a configuration diagram of a propulsion control apparatus according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in that a third power converter3connected to the direct-current common section20, a generator5A connected to the third power converter3, and a diesel engine7A connected to the generator5A are added, and in that a control device110is used instead of the control device100. In the following explanation, components same as the components in the first embodiment are denoted by the same reference numerals and signs and explanation of the components is omitted. Only different components are explained.

The propulsion control apparatus according to the second embodiment is configured by including, as main components, the first motor4, the second motor4A, the diesel engine7, the generator5, the diesel engine7A, the generator5A, the control device110, the first power converter1, the second power converter2, the third power converter3, and the power storage device9. InFIG. 10, the second motor4A is not shown to simplify explanation. However, the second motor4A can be provided as in the first embodiment or the propulsion control apparatus can be configured by omitting the second motor4A.

Two diesel engines7and7A are used in the propulsion control apparatus according to the second embodiment. The diesel engine7A is connected to the generator5A, which is one of power supply sources that generate electric power. The generator5A is an alternating-current generator driven by the diesel engine7A. The generator5A is supplied with alternating-current power by the third power converter3and operates as an alternating-current electric motor as well.

The third power converter3operates as an AC/DC converter or a DC/AC converter. When the third power converter3operates as an AC/DC converter, alternating-current power generated by the generator5A is supplied to a second input/output end C2side located on the generator5A side of the third power converter3. In the third power converter3, the alternating-current power is converted into direct-current power. The direct-current power is charged to the power storage device9.

When the third power converter3operates as a DC/AC converter, direct-current power from the power storage device9is supplied to a first input/output end C1side located on the direct-current common section20side of the third power converter3. In the third power converter3, the direct-current power is converted into alternating-current power. The alternating-current power is supplied to the generator5A and the generator5A is driven.

A fifth line breaker15and a sixth line breaker16are connected in series and inserted between the direct-current common section20and the third power converter3. A fifth voltage detector52detects a voltage EFC3of a third filter capacitor42. A fourth current detector62detects a direct current IS3flowing into and out of the third power converter3. A sixth current detector82detects an alternating current IM3flowing into and out of the third power converter3. A fourth speed detector92detects rotating speed (generator rotating speed) PG4of the generator5A. Detection values detected by the sensors are input to the control device110. Note that, besides the detection values, values equivalent to the detection values input to the control device100in the first embodiment are input to the control device110. Further, an operation command from a not-shown motorman's platform is also input to the control device110.

The control device110switches an operation mode of the vehicle according to the operation command and generates, on the basis of the detection values from the various sensors, signals (PWM1, PWM2, and PWM3) for controlling not-shown switching elements of the power converters, a signal (HB) for controlling ON/OFF of the high-speed breaker10, signals (LB11to32) for controlling ON/OFF of the line breakers, and signals (LS11to22) for controlling ON/OFF of the contactors and outputs the signals to the respective control target sections. Answerbacks from the devices are input to the control device110.

Note that, inFIG. 10, the diesel engine7A and the generator5A are respectively represented as “ENG2” and “G2”. The third power converter3is represented focusing on functions thereof. For example, when the third power converter3operates as an AC/DC converter, the third power converter3is represented as “CNV3”. When the third power converter3operates as a DC/AC converter, the third power converter3is represented as “INV3”.

Operations in respective modes in the propulsion control apparatus according to the second embodiment are explained.

FIG. 11is a diagram of states of the devices during the departure of the vehicle. When an operation command indicating departure is input to the control device110, to reduce noise of the diesel engine7and the diesel engine7A, the control device110causes the first power converter1to perform an inverter operation. In the first power converter1, direct-current power from the power storage device9is converted into the alternating-current power. The first motor4is driven by the alternating current power.

More specifically, when confirming that the voltage EB of the power storage device9is a voltage in a normal range, the control device110turns on the high-speed breaker10. When confirming that the voltage ES of the direct-current common section20is a voltage in a normal range, the control device110turns on the first line breaker11. The first filter capacitor40is charged while an electric current is limited by the first charging resistor30. When detecting with the first voltage detector50that the first filter capacitor40has been charged to a predetermined voltage, the control device110turns on the second line breaker12and short-circuits the first charging resistor30. The control device110confirms that the fifth contactor75is off and turns on the first contactor71, turns on the second contactor72, turns off the third contactor73, and turns off the fourth contactor74. The control device110causes the first power converter1to operate as a DC/AC converter (INV1). In the power converter1, direct-current power from the power storage device9is converted into alternating-current power, and the first motor4is driven by the alternating-current power and the vehicle travels. Note that the other devices are set in an OFF state. According to this operation, the first motor4is driven using stored power of the power storage device9. Therefore, it is made possible to reduce the noise of the diesel engines7and7A.

FIG. 12is a diagram of an operation in starting the diesel engines7and7A using the stored power of the power storage device9. When the hybrid railroad vehicle reaches predetermined speed (or a predetermined travel distance, a predetermined time, or it can be an operation of a motorman, or a command from a railroad system), the control device110turns on the third line breaker13and charges the second filter capacitor41while limiting an electric current with the second charging resistor31. When confirming with the voltage detected by the second voltage detector51that the second filter capacitor41has been charged to a predetermined voltage, the control device110turns on the fourth line breaker14and short-circuits the second charging resistor31. The control device110confirms that the fifth contactor75is off and turns on the third contactor73and turns on the fourth contactor74. The control device110causes the second power converter2to operate as a DC/AC converter (INV2). In the second power converter2, direct-current power from the power storage device9is converted into alternating-current power. The generator5is caused to operate as a motor by the alternating-current power to start the diesel engine7.

Similarly, the control device110turns on the fifth line breaker15and charges the third filter capacitor42while limiting an electric current with a third charging resistor32. When confirming with the voltage detected by the fifth voltage detector52that the third filter capacitor42has been charged to a predetermined voltage, the control device110turns on the sixth line breaker16and short-circuits the third charging resistor32. The control device110causes the third power converter3to operate as a DC/AC converter (INV3). In the third power converter3, direct-current power from the power storage device9is converted into alternating-current power, and the generator5A is caused to operate as a motor by the alternating-current power to start the diesel engine7A.

Note that, in the propulsion control apparatus according to the second embodiment, by shifting start timings of the diesel engine7and the diesel engine7A, it is possible to reduce the maximum of discharge power from the power storage device9, suppress deterioration of the power storage device9, and extend the life of the power storage device9. For example, the propulsion control apparatus can be configured to start the diesel engine7A after the control device110confirms that the diesel engine7has started. If the propulsion control apparatus is configured in this way, depending on a peripheral situation of the vehicle, for example, when the vehicle is present in the vicinity of a place crowded with people such as a station, it is possible to reduce the influence due to the noise of the diesel engines7and7A. Note that whichever of the two diesel engines7and7A can be started first.

FIG. 13is a diagram of an operation in driving the first motor4using generated power of the generators and the stored power of the power storage device9. When the diesel engine7is started by the operation shown inFIG. 12, after once stopping the inverter operation of the second power converter2, the control device110causes the second power converter2to restart as an AC/DC converter (CNV2). Similarly, after once stopping the inverter operation of the third power converter3, the control device110causes the third power converter3to restart as an AC/DC converter (CNV3). The control device110causes the first power converter1to operate as a DC/AC converter (INV1). In the first power converter1, direct-current power from the power storage device9, the second power converter2, and from the third power converter3is converted into alternating-current power. The first motor4is driven by the alternating-current power and the vehicle accelerates.

FIG. 14is a diagram of states of the devices during coasting. When a power running command from the motorman's platform is turned off, the control device110stops the inverter operation of the first power converter1and turns off the first line breaker11and turns off the second line breaker12. In this case, when a state of charge (SOC) of the power storage device9is low, the power generation of the generator5driven by the diesel engine7is continued. The generated power is converted into direct-current power and charged to the power storage device9by the second power converter2. Similarly, the power generation of the generator5A driven by the diesel engine7A is continued. The generated power is converted into direct-current power and charged to the power storage device9by the third power converter3. Depending on a value of the SOC of the power storage device9, any one of the diesel engines7and7A can be stopped to reduce total generated power, and thus it is made possible to reduce the noise of the diesel engines.

FIG. 15is a diagram of states of the devices during braking. During the braking, the control device110causes the first motor4to operate as a generator. Regenerative electric power from the first motor4is input to the first power converter1. The control device110causes the first power converter1to operate as an AC/DC converter (CNV1). The first power converter1converts the regenerative electric power from the first motor4into direct-current power and charges the power storage device9.

In this case, if the SOC of the power storage device9is lower than a predetermined value in a case in which the power storage device9is charged only by the regenerative electric power, the control device110drives the diesel engine7. The generated power from the generator5is input to the second power converter2. The control device110causes the second power converter2to operate as an AC/DC converter (CNV2). The second power converter2converts the generated power from the generator5into direct-current power and charges the power storage device9. Similarly, the control device110drives the diesel engine7A. The generated power from the generator5A is input to the third power converter3. The control device110causes the third power converter3to operate as an AC/DC converter (CNV3). The third power converter3converts the generated power from the generator5A into direct-current power and charges the power storage device9.

On the other hand, if the SOC of the power storage device9is higher than the predetermined value or if the power storage device9cannot be charged, the control device110causes the second power converter2to operate as a DC/AC converter (INV2). Direct-current power from the first power converter1is input to the second power converter2. The second power converter2converts the direct-current power into alternating-current power and causes the generator5to operate as a motor. The second power converter2causes the diesel engine7to operate as an engine brake (further as an exhaust brake) and consume electric power. Similarly, the control device110causes the third power converter3to operate as a DC/AC converter (INV3). Direct-current power from the first power converter1is input to the third power converter3. The third power converter3converts the direct-current power into alternating-current power and causes the generator5A to operate as a motor. The third power converter3causes the diesel engine7A to operate as an engine brake (further as an exhaust brake) and consume electric power. Note that, inFIG. 15, to simplify explanation, a state in the case in which the SOC of the power storage device9is higher than the predetermined value is shown.

According to the operation shown inFIG. 15, it is possible to continue the regenerative brake and suppress wear of brake shoes. Therefore, it is possible to suppress odor involved in the wear of the brake shoes. The life of the brake shoes is extended and a replacement cycle of the brake shoes is extended. It is possible to reduce costs. The propulsion control apparatus according to the second embodiment can be configured to cause only any one of the diesel engines7and7A to operate as the engine brake. If the propulsion control apparatus is configured in this way, it is possible to reduce the noise of the diesel engines7and7A.

FIG. 16is a diagram of states of the devices during the stopped state of the vehicle. When the vehicle is stopped, for example, if power consumption in the vehicle by not-shown auxiliary power supply devices is large or if the SOC of the power storage device9is lower than the predetermined value, the control device110drives the diesel engine7. The generated power from the generator5is input to the second power converter2. The control device110causes the second power converter2to operate as an AC/DC converter (CNV2). The second power converter2converts the generated power from the generator5into direct-current power and charges the power storage device9.

Similarly, for example, if the SOC of the power storage device9is lower than the predetermined value, the control device110drives the diesel engine7A. The generated power from the generator5A is input to the third power converter3. The control device110causes the third power converter3to operate as an AC/DC converter (CNV3). The third power converter3converts the generated power from the generator5A into direct-current power and charges the power storage device9.

When the SOC of the power storage device9is high or when the power consumption in the vehicle by the not-shown auxiliary power supply devices is small, the control device110stops the diesel engine7or the diesel engine7A. Consequently, it is possible to reduce noise and suppress fuel consumption.

FIG. 17is a diagram of states of the devices in the case of a breakdown of the first power converter1. When detecting a breakdown of the first power converter1, first, the control device110turns off the first line breaker11, the second line breaker12, and the first contactor71. Consequently, the first input/output end A1of the first power converter1is disconnected from the power storage device9. The second input/output end A2of the first power converter1is disconnected from the first motor4.

Subsequently, the control device110stops the converter operation of the second power converter2and further turns off the fourth contactor74. Consequently, the second input/output end B2of the second power converter2is disconnected from the generator5. Thereafter, the control device110turns on the fifth contactor75and causes the second power converter2to operate as a DC/AC converter (INV2). The control device110causes the third power converter3to operate as an AC/DC converter (CNV3). Consequently, direct-current power converted by the third power converter3is supplied to the second power converter2. The second power converter2converts the direct-current power from the power storage device9and the third power converter3into alternating-current power and drives the first motor4.

As explained above, in the propulsion control apparatus according to the second embodiment, even when the first power converter1is broken down, it is possible to cause the second power converter2to perform the inverter operation and cause the third power converter3to perform the converter operation. Therefore, it is possible to drive the diesel engine7A and cause the vehicle to travel until the volume of gas oil in a fuel tank mounted on the vehicle reaches the lower limit. It is possible to continuously drive the first motor4and increase vehicle speed or increase a travel distance compared with the first embodiment.

FIG. 18is a diagram of states of the devices in the case of a breakdown of the second power converter2. When detecting a breakdown of the second power converter2, as shown inFIG. 18, the control device110turns off the third line breaker13, the fourth line breaker14, and the third contactor73. Consequently, the first input/output end B1of the second power converter2is disconnected from the power storage device9. The second input/output end B2of the second power converter2is disconnected from the generator5.

In this case, if the SOC of the power storage device9is higher than the predetermined value, the control device110turns off the fifth contactor75, causes the first power converter1to operate as a DC/AC converter (INV1), and causes the third power converter3to operate as an AC/DC converter (CNV3). Consequently, direct-current power converted by the third power converter3is supplied to the first power converter1. The first power converter1converts the direct-current power from the power storage device9and the third power converter3into alternating-current power and drives the first motor4.

As explained above, in the propulsion control apparatus according to the second embodiment, even when the second power converter2is broken down, it is possible to cause the first power converter1to perform the inverter operation and cause the third power converter3to perform the converter operation. Therefore, it is possible to drive the diesel engine7A and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit. It is possible to continuously drive the first motor4. Therefore, it is possible to increase vehicle speed or increase a travel distance compared with the first embodiment.

FIG. 19is a diagram of states of the devices in the case of a breakdown of the third power converter3. When detecting a breakdown of the third power converter3, as shown inFIG. 19, the control device110turns off the fifth line breaker15and the sixth line breaker16. Consequently, the first input/output end C1of the third power converter3is disconnected from the power storage device9. The second input/output end C2of the third power converter3is disconnected from the generator5A.

In this case, if the SOC of the power storage device9is higher than the predetermined value, the control device110turns off the fifth contactor75, causes the first power converter1to operate as a DC/AC converter (INV1), and causes the second power converter2to operate as an AC/DC converter (CNV2). Consequently, direct-current power converted by the second power converter2is supplied to the first power converter1. The first power converter1converts the direct-current power from the power storage device9and the second power converter2into alternating-current power and drives the first motor4.

As explained above, in the propulsion control apparatus according to the second embodiment, even when the third power converter3is broken down, it is possible to cause the first power converter1to perform the inverter operation and cause the second power converter2to perform the converter operation. Therefore, it is possible to drive the diesel engine7and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit. It is possible to continuously drive the first motor4. Therefore, it is possible to increase vehicle speed or increase a travel distance compared with the first embodiment.

As explained above, in the propulsion control apparatus according to the second embodiment, the generator is divided into the first generator (5) and the second generator (5A) respectively driven by the first engine (7) and the second engine (7A). The propulsion control apparatus includes the third power converter3that is configured to be connectable to the direct-current common section20and, when direct-current power from the direct-current common section20is input from the first input/output end C1side, operates as a DC/AC converter, outputs desired alternating-current power from the second input/output end C2side different from the first input/output end C1, and supplies the desired alternating-current power to the second generator5A, and, when alternating-current power from the second generator5A is input from the second input/output end C2side, operates as an AC/DC converter and outputs desired direct-current power from the first input/output end C1side. The control device110is configured to, when the first power converter1is broken down, cause the third power converter3to operate as a DC/AC converter and supply alternating-current power from the third power converter3to the second generator5A and, after the generator5A starts, cause the third power converter3to operate as an AC/DC converter and supply direct-current power from the third power converter3to the direct-current common section20. Therefore, even when the first power converter1is broken down, it is possible to cause the second power converter2to perform the inverter operation and cause the third power converter3to perform the converter operation. It is possible to drive the diesel engine and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit. It is possible to increase vehicle speed or increase a travel distance compared with the first embodiment.

The control device110according to the second embodiment is configured to, when the second power converter2is broken down, if the SOC of the power storage device9is lower than the predetermined value, cause the third power converter3to operate as a DC/AC converter and supply alternating-current power from the third power converter3to the second generator and, after the second engine (7A) starts, cause the third power converter3to operate as an AC/DC converter and supply direct-current power from the third power converter3to the direct-current common section20. Therefore, even when the second power converter2is broken down, it is possible to cause the first power converter1to perform the inverter operation and cause the third power converter3to perform the converter operation. It is possible to drive the diesel engine and cause the vehicle to travel until the volume of gas oil in the fuel tank (not shown in the figure) mounted on the vehicle reaches the lower limit. It is possible to increase vehicle speed or increase a travel distance compared with the first embodiment.

Note that, in the first and second embodiments, the first motor4and the second motor4A are used. However, the same effects can be obtained when only the first motor4is used. That is, the propulsion control apparatuses according to the first and second embodiments are configured to include the motor configured to be drivable by the first power converter1, the group of switches (71,72,73,74, and75) that switches an electric connection destination of the generator5from the second input/output end B2side of the second power converter2to the second input/output end A2side of the first power converter1or switches an electric connection destination of the motor4from the second input/output end A2side of the first power converter1to the second input/output end B2side of the second power converter2, and the control units (the control devices100and110) that control, according to operation forms of the first and second power converters1and2, the operations of the first power converter1, the second power converter2, and the group of switches. With this configuration, connection states between the motor4and the first power converter1and the second power converter2are controlled, and the motor4is driven by the first power converter1or the second power converter2.

The first input/output end side explained in the first and second embodiments represents, for example, when a switching element is connected in series, a terminal side to which a plurality of the switching elements connected in series are connected in parallel. The second input/output end side represents, when a switching element is connected in series, a terminal side of a point of the series connection.

The propulsion control apparatuses of the engine hybrid railroad vehicle explained in the embodiments indicate an example of contents of the present invention. It goes without saying that the propulsion control apparatuses can be combined with still other publicly-known technologies and can be configured to be changed to, for example, omit a part thereof in a range not departing from the spirit of the present invention.

INDUSTRIAL APPLICABILITY

As explained above, the present invention is applicable to the propulsion control apparatus of the engine hybrid railroad vehicle. In particular, the present invention is useful as an invention that can attain further improvement of efficiency of a railroad vehicle even in a configuration in which a plurality of motors are driven by one power conversion device.

REFERENCE SIGNS LIST