JP7604233B2 - Electric vehicle control device - Google Patents

Description

An embodiment of the present invention relates to an electric vehicle control device.

There are railway vehicle drive systems that use permanent magnet synchronous motors to drive the wheels on the powered bogie. Permanent magnet synchronous motors require a voltage to be applied from an inverter in accordance with the rotation of the rotor. For this reason, railway vehicle drive systems that use permanent magnet synchronous motors need to have an inverter for each permanent magnet synchronous motor. For example, multiple inverters are consolidated into a single cooling unit that uses the wind generated by the vehicle while it is running, and installed on the vehicle.

The wheels provided on the powered bogie include, for example, a first wheel and a second wheel. The first wheel and the second wheel are arranged along the traveling direction of the vehicle. When the traveling direction of the vehicle is a predetermined direction (first direction), the first wheel is in the front of the traveling direction of the vehicle, and the second wheel is in the rear of the traveling direction of the vehicle. In such a case, due to the shift of the axle load, the first wheel has a lighter axle load than the second wheel. A railway vehicle drive system using a permanent magnet synchronous motor controls the current supplied from the first inverter to the first motor that drives the first wheel to be smaller than the current supplied from the second inverter to the second motor that drives the second wheel. The first inverter is provided behind (downwind side) of the cooling unit in the traveling direction of the vehicle, and the second inverter is provided ahead (wind side) of the cooling unit in the traveling direction of the vehicle. For this reason, the second inverter has better cooling conditions than the first inverter. As a result, the railway vehicle drive system can suppress the temperature rise of the inverter while ensuring adhesion performance.

However, the thermal time constant of the cooling system of the inverter is small, and the temperature rises quickly due to the current. For this reason, if there is an imbalance between the current of the first inverter and the current of the second inverter, the current can cause an extreme temperature rise, which can shorten the life of the inverter.

JP 2013-201800 A

The problem that this invention aims to solve is to provide an electric vehicle control device that can suppress the temperature rise of the inverter.

An electric vehicle control device according to an embodiment includes a first motor, a second motor, a first inverter, a second inverter, a temperature estimator, and a current command calculation circuit. The first motor drives a first wheel of a vehicle. The second motor drives a second wheel of the vehicle that is disposed rearward of the first wheel in the traveling direction. The first inverter supplies a current to the first motor. The second inverter is disposed forward of the first inverter in the traveling direction of the vehicle and supplies a current to the second motor. The temperature estimator estimates temperatures of semiconductor switching elements of the first inverter and the second inverter. The current command calculation circuit controls current command values of the first inverter and the second inverter based on a result of temperature estimation by the temperature estimator, and the current command calculation circuit controls current command values of the first inverter and the second inverter such that the temperature of the semiconductor switching elements of the second inverter does not exceed the temperature of the semiconductor switching elements of the first inverter .

FIG. 1 is a diagram for explaining an example of the configuration of an electric vehicle control device according to the first embodiment. FIG. 2 is an explanatory diagram for explaining an example of the arrangement of each component of the electric vehicle control device according to the first embodiment. FIG. 3 is an explanatory diagram for explaining a configuration example of the cooling unit according to the first embodiment. FIG. 4 is an explanatory diagram for explaining a configuration example of the inverter device according to the first embodiment. FIG. 5 is an explanatory diagram for explaining a configuration example of the current command calculation circuit according to the first embodiment. FIG. 6 is an explanatory diagram for describing an example of the configuration of the temperature estimating unit according to the first embodiment. FIG. 7 is an explanatory diagram for explaining a configuration example of a ratio adjuster according to the second embodiment. FIG. 8 is an explanatory diagram for explaining a configuration example of a cooling unit according to the third embodiment. FIG. 9 is an explanatory diagram for explaining a configuration example of a current command calculation circuit according to the third embodiment.

Hereinafter, an embodiment will be described with reference to the drawings.
First Embodiment
Fig. 1 is an explanatory diagram showing an example of the configuration of an electric vehicle control device 1 according to a first embodiment. Fig. 2 is an explanatory diagram for explaining an example of the arrangement of each component of the electric vehicle control device 1.

The electric vehicle control device 1 is mounted on a moving vehicle 2 such as an electric vehicle. The electric vehicle control device 1 receives DC power from a train line 3 such as an overhead train line or a third rail via a current collector 4, converts the received DC power into AC power according to the rating of a permanent magnet synchronous motor 5, which is a load, and supplies the AC power to the permanent magnet synchronous motor 5.

In this embodiment, the electric vehicle control device 1 is described as a power supply device that supplies AC power (three-phase AC power) to a permanent magnet synchronous motor 5 (three-phase induction motor) for powering the electric vehicle on a track 6.

The electric vehicle control device 1 includes a boost circuit 11, a power conversion circuit 12, an inverter device 13, and a main control circuit 14.

The boost circuit 11 boosts the DC power input from the electric rail 3 via the current collector 4. The boost circuit 11 includes a boost reactor and a boost chopper.

The boost chopper includes a switch and a diode. The boost chopper controls the current flowing through the boost reactor by controlling the switch on and off based on the control of the main control circuit 14. As a result, the boost chopper outputs a DC voltage boosted by the electromagnetic energy stored in the boost reactor. The boost chopper may also include a filter capacitor that stabilizes the output DC voltage.

The power conversion circuit 12 converts the DC power output from the boost circuit 11 into power for a DC load. The power conversion circuit 12 includes, for example, a resonant inverter 21, a transformer 22, a rectifier circuit 23, and a smoothing circuit 24.

The resonant inverter 21 is a circuit that supplies AC current (such as inverter current or single-phase AC current) to the transformer 22 using DC voltage supplied from a boost chopper. The resonant inverter 21 is configured, for example, as a resonant type single-phase half-bridge inverter. The resonant inverter 21 includes a switch and a capacitor. The resonant inverter 21 supplies AC current from the capacitor to the transformer 22 by controlling the on/off of the switch.

The transformer 22 is an isolation transformer having a primary winding (primary winding) that generates magnetic flux, and a secondary winding (secondary winding) that is insulated from the primary winding and excited by the magnetic flux generated in the primary winding. When AC current is supplied from the resonant inverter 21 to the primary winding of the transformer 22, the magnetic flux generated in the primary winding changes. The magnetic flux generated in the primary winding generates an induced current in the secondary winding. As a result, the transformer 22 supplies power to the secondary side according to the AC current input from the primary side.

The rectifier circuit 23 is a circuit that rectifies the power generated in the secondary winding of the transformer 22. The rectifier circuit 23 is configured, for example, as a rectifier bridge in which multiple diodes are combined.

The smoothing circuit 24 smoothes the positive voltage supplied from the rectifier circuit 23. The smoothing circuit 24 includes, for example, a smoothing capacitor. The smoothing circuit 24 supplies a high-voltage DC voltage to the inverter device 13 connected in parallel.

The inverter device 13 converts DC power into AC power (three-phase AC power) and outputs it to the traction motor, which is a permanent magnet synchronous motor 5. The inverter device 13 includes multiple inverters, multiple temperature sensors, and an inverter control circuit. Specifically, the inverter device 13 includes a first inverter 31, a second inverter 32, a first temperature sensor 33, a second temperature sensor 34, and an inverter control circuit 35.

The first inverter 31 and the second inverter 32 each have three legs made up of a plurality of semiconductor switches that form an upper arm and a lower arm. For example, the first inverter 31 and the second inverter 32 each have a first leg, a second leg, and a third leg.

The first leg, the second leg, and the third leg are each connected in parallel to the smoothing circuit 24. The first leg, the second leg, and the third leg supply AC voltage to the permanent magnet synchronous motor 5 by DC voltage from the smoothing circuit 24. The first leg, the second leg, and the third leg supply AC voltages of different phases to the permanent magnet synchronous motor 5. Specifically, the first leg, the second leg, and the third leg supply AC voltages of different phases by 120° to the permanent magnet synchronous motor 5. As a result, the first inverter 31 and the second inverter 32 supply three-phase AC power to the permanent magnet synchronous motor 5.

The first inverter 31 supplies three-phase AC power to the first motor 71 of the permanent magnet synchronous motor 5.

The second inverter 32 supplies three-phase AC power to the second motor 72 of the permanent magnet synchronous motor 5.

The first temperature sensor 33 and the second temperature sensor 34 each detect the temperature inside the inverter. The first temperature sensor 33 and the second temperature sensor 34 are, for example, thermistors provided near semiconductor switches inside the inverter. The first temperature sensor 33 and the second temperature sensor 34 may also be composed of a thermocouple or the like.

The first temperature sensor 33 detects the temperature inside the first inverter 31. The first temperature sensor 33 outputs the temperature detection result to the inverter control circuit 35.

The second temperature sensor 34 detects the temperature inside the second inverter 32. The second temperature sensor 34 outputs the temperature detection result to the inverter control circuit 35.

The inverter control circuit 35 controls the operation of the inverter device 13 based on instructions from the main control circuit 14, the temperature detection results from the first temperature sensor 33, and the temperature detection results from the second temperature sensor 34. The detailed configuration of the inverter control circuit 35 will be described later.

As shown in FIG. 2, the vehicle 2 is also provided with a powered bogie 41 that supports the vehicle body on the track 6 and a cooling unit 42.

The powered bogie 41 is provided with a first wheel 51, a second wheel 52, and a permanent magnet synchronous motor 5.

The first wheel 51 and the second wheel 52 are a mechanism for powering the vehicle 2. The first wheel 51 and the second wheel 52 are aligned along the traveling direction of the vehicle 2. For example, when the traveling direction of the vehicle 2 is the first direction 61, the first wheel 51 is in the front of the traveling direction of the vehicle 2, and the second wheel 52 is in the rear of the traveling direction of the vehicle 2. Therefore, when the vehicle 2 is traveling in the first direction 61, the axle load of the first wheel 51 is lighter than that of the second wheel 52. In addition, when the vehicle 2 is traveling in the first direction 61, a traveling wind is generated in the second direction 62, which is the opposite direction to the first direction 61.

The permanent magnet synchronous motor 5 also has a first motor 71 and a second motor 72.

The first motor 71 and the second motor 72 are each operated by current from an inverter, rotating the first wheel 51 and the second wheel 52, and powering the vehicle 2.

The first motor 71 is connected to the first inverter 31. The first motor 71 rotates the rotor using power from the first inverter 31. The first wheel 51 is connected to the rotating shaft of the rotor via a mechanism such as a gear. That is, the first motor 71 drives the first wheel 51 using power from the first inverter 31.

The second motor 72 is connected to the second inverter 32. The second motor 72 rotates the rotor using power from the second inverter 32. The second wheel 52 is connected to the rotating shaft of the rotor via a mechanism such as a gear. That is, the second motor 72 drives the second wheel 52 using power from the second inverter 32.

The cooling unit 42 houses the first inverter 31, the second inverter 32, the first temperature sensor 33, the second temperature sensor 34, and the inverter control circuit 35.

Figure 3 is an explanatory diagram for explaining an example of the structure of the cooling unit 42.

The cooling unit 42 has a storage section 81 and an air intake 82.

The accommodation section 81 is a space that accommodates the first inverter 31, the second inverter 32, the first temperature sensor 33, the second temperature sensor 34, and the inverter control circuit 35.

For example, the first inverter 31 and the second inverter 32 are arranged in the accommodation section 81 with the circuit portion including the semiconductor switching element accommodated in a housing or the like. The semiconductor switching element is, for example, a power semiconductor element such as an IGBT. The first inverter 31 and the second inverter 32 are arranged in the accommodation section 81 so as to be aligned in the first direction 61, which is the traveling direction of the vehicle 2. Specifically, the first inverter 31 is arranged in the accommodation section 81 behind the second inverter 32 in the first direction 61. That is, the second inverter 32 is arranged in the accommodation section 81 forward of the first inverter 31 in the first direction 61.

The air intake 82 is a hole for taking in the traveling wind into the storage section 81. The air intake 82 is formed, for example, in a position facing the second direction 62, which is the opposite direction to the first direction 61, which is the traveling direction. The air intake 82 is formed, for example, in the shape of a slit in front of the cooling unit 42 in the first direction 61.

With the above configuration, the running wind that enters the storage section 81 from the air intake 82 hits the housing of the second inverter 32 before the first inverter 31, travels through the storage section 81, and hits the housing of the first inverter 31. In other words, since the first inverter 31 is provided behind the vehicle 2 in the traveling direction (downwind side) and the second inverter 32 is provided ahead of the vehicle 2 in the traveling direction (upwind side), the second inverter 32 has better cooling conditions than the first inverter 31.

The main control circuit 14 controls the operation of the boost circuit 11, the power conversion circuit 12, and the inverter device 13. The main control circuit 14 outputs an operation command to the inverter device 13, for example, in response to the operation of a driver's console (not shown). The main control circuit 14 controls the output of the boost circuit 11, the output of the power conversion circuit 12, and the output of the inverter device 13. For example, the main control circuit 14 includes a processor, which is a calculation element that executes calculation processing, and a memory that stores programs and data used in the programs, and outputs an operation command to the inverter device 13 by the processor executing the program.

Next, the control in the inverter device 13 will be described in detail.
FIG. 4 is an explanatory diagram for explaining an example of the configuration of the inverter control circuit 35 of the inverter device 13. As shown in FIG.

The inverter control circuit 35 includes a first PWM controller 91, a second PWM controller 92, a first current controller 93, a second current controller 94, a current command calculation circuit 95, and a temperature estimation unit 96.

The first PWM controller 91 calculates a PWM gate command according to the control from the first current controller 93, and controls the corresponding first inverter 31. This drives the first motor 71.

The second PWM controller 92 calculates a PWM gate command according to the control from the second current controller 94, and controls the corresponding second inverter 32. This drives the second motor 72.

The first current controller 93 outputs a control signal to the first PWM controller 91 based on the command value of the current flowing from the current command calculation circuit 95 so that a current corresponding to the command value is output from the first inverter 31.

The second current controller 94 outputs a control signal to the second PWM controller 92 based on the command value of the current flowing from the current command calculation circuit 95 so that a current corresponding to the command value is output from the second inverter 32.

The current command calculation circuit 95 calculates a command value for the current flow based on the control from the main control circuit 14 and the temperature information from the temperature estimation unit 96, and outputs it to the first current controller 93 and the second current controller 94, respectively. The temperature information is information related to the temperature of the semiconductor switching element in the first inverter 31 and/or the temperature of the semiconductor switching element in the second inverter 32. The current command calculation circuit 95 adjusts the ratio between the current supplied from the first inverter 31 to the first motor 71 and the current supplied from the second inverter 32 to the second motor 72 based on the control from the main control circuit 14 and the temperature information from the temperature estimation unit 96.

The temperature estimation unit 96 acquires temperature detection results from the first temperature sensor 33 and the second temperature sensor 34. The temperature estimation unit 96 estimates the temperature of the semiconductor switching element in the first inverter 31 based on the temperature detection result from the first temperature sensor 33. The temperature estimation unit 96 also estimates the temperature of the semiconductor switching element in the second inverter 32 based on the temperature detection result from the second temperature sensor 34. The temperature estimation unit 96 outputs temperature information to the current command calculation circuit 95 based on the estimated temperature of the semiconductor switching element in the first inverter 31 and the estimated temperature of the semiconductor switching element in the second inverter 32.

FIG. 5 is an explanatory diagram for explaining the detailed configuration of the current command calculation circuit 95. As shown in FIG.
The current command calculation circuit 95 includes a current pattern generator 101 , a constant output unit 102 , a ratio adjuster 103 , a subtractor 104 , an adder 105 , a first multiplier 106 , and a second multiplier 107 .

The current pattern generator 101 calculates the current pattern to be output from the inverter to the permanent magnet synchronous motor 5 based on a control signal (operation command) from the main control circuit 14. The current pattern generator 101 outputs the current pattern to the first multiplier 106 and the second multiplier 107, respectively.

The constant output unit 102 outputs a constant to the subtractor 104 and the adder 105. Specifically, the constant output unit 102 outputs a voltage equivalent to the constant "1" to the subtractor 104 and the adder 105 based on the reference voltage in the current command calculation circuit 95.

The ratio adjuster 103 adjusts the ratio between the current output from the first inverter 31 to the first motor 71 and the current output from the second inverter 32 to the second motor 72. Specifically, the ratio adjuster 103 outputs a signal K for adjusting the ratio to the subtractor 104 and the adder 105 based on temperature information from the temperature estimation unit 96. The voltage of the signal K is adjusted in the vehicle 2 in which the ratio adjuster 103 is actually mounted, to a value calculated in advance based on a known formula. Specifically, the signal K has a value of about "0.03" to "0.1" with respect to the constant "1" output from the constant output unit 102.

The subtractor 104 subtracts the signal K output from the ratio adjuster 103 from the constant "1" output from the constant output unit 102, and outputs the signal resulting from the subtraction to the first multiplier 106.

The adder 105 adds the signal K output from the ratio adjuster 103 to the constant "1" output from the constant output unit 102, and outputs the result to the second multiplier 107.

The first multiplier 106 multiplies the current pattern output from the current pattern generator 101 by the signal output from the subtractor 104, and outputs the result to the first current controller 93 as a command value for the current flow.

The second multiplier 107 multiplies the current pattern output from the current pattern generator 101 by the signal output from the adder 105, and outputs the result to the second current controller 94 as a command value for the current flow.

FIG. 6 is an explanatory diagram for explaining the detailed configuration of the temperature estimation unit 96. As shown in FIG.
First, a schematic configuration within the inverter will be described. Here, the first inverter 31 will be described as an example. The first inverter 31 has an isolated power supply circuit 111, a gate driver 112, and an inverter main circuit 113. A first temperature sensor 33 is provided near the inverter main circuit 113 of the first inverter 31. A second temperature sensor 34 is provided near the inverter main circuit 113 of the second inverter 32.

The isolated power supply circuit 111 outputs a DC voltage from an AC power supply via a transformer and a smoothing bridge to turn on and off the semiconductor switching elements of the inverter main circuit 113.

The gate driver 112 controls the timing of outputting a DC voltage from the isolated power supply circuit 111 to the semiconductor switching element of the inverter main circuit 113 based on a PWM gate command from the first PWM controller 91.

The inverter main circuit 113 has multiple semiconductor switching elements. When the semiconductor switching elements are turned on and off by the gate driver 112, the inverter main circuit 113 converts the DC power from the smoothing circuit 24 into AC power (three-phase AC power) and outputs it to the first motor 71.

The temperature estimation unit 96 has a temperature estimation unit power supply 121, a signal transmission unit 122, and a signal isolation circuit 123.

The temperature estimation unit power supply 121 supplies power to the signal transmission unit 122 from the isolated power supply circuit 111. The temperature estimation unit power supply 121 may be configured to obtain power from the first inverter 31 or may be configured to obtain power from the second inverter 32.

The signal transmission unit 122 acquires the temperature detection results from the first temperature sensor 33 and the second temperature sensor 34. Based on the temperature detection results acquired from the first temperature sensor 33 and the second temperature sensor 34, the signal transmission unit 122 outputs temperature information to the current command calculation circuit 95 via a signal isolation circuit 123 such as a photocoupler.

The current command calculation circuit 95 outputs a command value of the current flow, the ratio of which is adjusted based on temperature information from the temperature estimation unit 96, to the first current controller 93 and the second current controller 94. In other words, the inverter control circuit 35 adjusts the ratio between the output current of the first inverter 31 and the output current of the second inverter 32 based on the temperature of the semiconductor switching element in the first inverter 31 and/or the temperature of the semiconductor switching element in the second inverter 32 by the temperature estimation unit 96.

Specifically, the inverter control circuit 35 adjusts the ratio between the output current of the first inverter 31 and the output current of the second inverter 32 so that the temperature of the inverter on the windward side is lower than the temperature of the inverter on the leeward side. That is, the inverter control circuit 35 adjusts the ratio between the output current of the first inverter 31 and the output current of the second inverter 32 so that the temperature of the semiconductor switching element of the second inverter 31 on the windward side is lower than the temperature of the semiconductor switching element of the first inverter 31 on the leeward side.

For example, when the inverter control circuit 35 predicts that the temperature of the semiconductor switching elements of the second inverter 31 on the windward side will be higher than the temperature of the semiconductor switching elements of the first inverter 31 on the leeward side, the inverter control circuit 35 controls to reduce the output current of the second inverter 32. That is, when the inverter control circuit 35 predicts that the temperature of the semiconductor switching elements of the second inverter 31 on the windward side will be higher than the temperature of the semiconductor switching elements of the first inverter 31 on the leeward side, the inverter control circuit 35 reduces the signal K from the ratio adjuster 103. As a result, the electric vehicle control device 1 can prevent a large temperature difference from occurring between the first inverter 31 and the second inverter 32.

Second Embodiment
The inverter control circuit 35 may adjust the ratio of the output current of the first inverter 31 to the output current of the second inverter 32 so that the temperature of the semiconductor switching element of the second inverter 31 on the windward side is lower than the temperature of the semiconductor switching element of the first inverter 31 on the downwind side, and so that the temperature of the semiconductor switching element of the second inverter 31 is less than a predetermined element temperature tolerance value.

As shown in FIG. 7, the ratio adjuster 103 has a clock generator 131, a comparator 132, and an LUT 133.

The clock generator 131 generates a clock signal and inputs it to the LUT 133.

The comparator 132 outputs the result of comparing the temperature information from the temperature estimation unit 96 with the element temperature tolerance to the LUT 133. In this case, the temperature information from the temperature estimation unit 96 is the result of estimating the temperature of the semiconductor switching element of the second inverter 32. In other words, the temperature information input to the comparator 132 is the result of estimating the temperature of the semiconductor switching element of the inverter that supplies power to the second motor 72 used to drive the second wheel 52, which is the rear wheel.

The LUT 133 outputs a signal K to the current command calculation circuit 95 based on the input comparison result and the clock signal.

With the above configuration, the ratio adjuster 103 controls the current command values of the first inverter 31 and the second inverter 32 so that the temperature of the semiconductor switching element of the second inverter 32 does not exceed a preset element temperature tolerance value. That is, when the inverter control circuit 35 predicts that the temperature of the semiconductor switching element of the second inverter 31 on the windward side and/or the temperature of the semiconductor switching element of the first inverter 31 on the leeward side will exceed the element temperature tolerance value, it reduces the signal K from the ratio adjuster 103. As a result, the electric vehicle control device 1 can prevent the temperature of the semiconductor switching element of the first inverter 31 or the second inverter 32 from exceeding the tolerance value.

The ratio adjuster 103 may also control the current command values of the first inverter 31 and the second inverter 32 so that the temperature of the semiconductor switching element of the second inverter 32 does not exceed a preset element temperature tolerance value, and the temperature of the semiconductor switching element of the second inverter 31 does not exceed the temperature of the semiconductor switching element of the first inverter 31. That is, when it is estimated that the temperature of the second inverter 31 and/or the temperature of the first inverter 31 will exceed the element temperature tolerance value, or when it is estimated that the temperature of the second inverter 31 will exceed the temperature of the first inverter 31, the inverter control circuit 35 lowers the signal K from the ratio adjuster 103. As a result, the electric vehicle control device 1 can prevent a large temperature difference from occurring between the first inverter 31 and the second inverter 32, and prevent the temperature of the first inverter 31 or the second inverter 32 from exceeding the tolerance value.

Third Embodiment
The third embodiment is different in that a temperature sensor is further provided in the cooling unit 42. The electric vehicle control device 1 of the third embodiment detects an abnormality such as a failure of a circuit within the inverter based on a comparison result between the temperature detection result of the temperature sensor provided in the cooling unit 42 and the temperature information of the first embodiment, i.e., the temperature detection result of the first inverter 31 and/or the second inverter 32.

Figure 8 is an explanatory diagram for explaining another example of the cooling unit 42. In the example of Figure 8, a third temperature sensor 141 is provided in the cooling unit 42.

The third temperature sensor 141 detects the temperature of the cooling unit 42. For example, the third temperature sensor 141 is provided in the housing 81 of the cooling unit 42, detects the temperature inside the housing 81 of the cooling unit 42, and outputs the detection result to the inverter control circuit 35. Also, for example, the third temperature sensor 141 may be provided outside the housing of the cooling unit 42, detects the temperature of the housing of the cooling unit 42, and outputs the detection result to the inverter control circuit 35. The third temperature sensor 141 is configured, for example, by a thermistor or a thermocouple.

Figure 9 is an explanatory diagram for explaining another example of the configuration of the current command calculation circuit 95 of the inverter control circuit 35. The current command calculation circuit 95 in Figure 9 differs from the example in Figure 5 in that it further includes an abnormality detection unit 142.

The abnormality detection unit 142 detects an abnormality based on the temperature detection result from the third temperature sensor 141 and the temperature information from the temperature estimation unit 96, and outputs an abnormality signal.

For example, the abnormality detection unit 142 outputs an abnormality signal to the ratio adjuster 103. When the ratio adjuster 103 receives the abnormality signal, it stops controlling the current command value.

Also, for example, the abnormality detection unit 142 may output an abnormality signal to the current pattern generator 101. When the current pattern generator 101 receives the abnormality signal, it stops outputting the current pattern.

Also, for example, the abnormality detection unit 142 may output an abnormality signal to the main control circuit 14. When the main control circuit 14 receives the abnormality signal, it outputs a control signal to the inverter device 13 to stop the operation of the first inverter 31 and the second inverter 32. For example, the main control circuit 14 stops the operation command to the inverter device 13.

The main control circuit 14 may also be configured to control the inverter device 13 so as not to perform regenerative braking when an abnormality signal is received.

Next, detection of anomalies by the anomaly detection unit 142 will be described.
The abnormality detection unit 142 calculates the deviation between the temperature detection result of the third temperature sensor 141 provided in the cooling unit 42 and the temperature estimation result by the temperature estimation unit 96. When the deviation is equal to or greater than a preset threshold value, the abnormality detection unit 142 outputs an abnormality signal.

Specifically, the abnormality detection unit 142 calculates the difference between the temperature detection result of the third temperature sensor 141 provided in the cooling unit 42 and the estimation result of the temperature of the semiconductor switching element of the first inverter 31 by the temperature estimation unit 96 and/or the estimation result of the temperature of the semiconductor switching element of the second inverter 32 by the temperature estimation unit 96. The abnormality detection unit 142 compares the calculated difference with a preset threshold value. If the calculated difference is equal to or greater than the threshold value as a result of the comparison, the abnormality detection unit 142 outputs an abnormality signal.

This allows the electric vehicle control device 1 to limit the operation of the inverter if it is suspected that an abnormality has occurred in the inverter.

In the above embodiment, an example in which the vehicle 2 moves in the first direction 61 has been described. However, when the vehicle 2 moves in the second direction 62, which is the opposite direction to the first direction 61, the inverter control circuit 35 adjusts the current command value so that the temperature of the first inverter 31 is lower than the temperature of the second inverter 32.

The functions described in each of the above embodiments can be realized not only by using hardware, but also by loading a program that describes each function into a computer using software. Also, each function may be configured by selecting either software or hardware as appropriate.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims.
[Appendix 1]
a first motor that drives a first wheel of the vehicle;
a second motor that drives a second wheel that is disposed rearward of the first wheel in a traveling direction of the vehicle;
a first inverter that supplies a current to the first motor;
a second inverter disposed forward of the first inverter in the traveling direction of the vehicle and configured to supply a current to the second motor;
a temperature estimator that estimates temperatures of semiconductor switching elements of the first inverter and the second inverter;
a current command calculation circuit that controls current command values of the first inverter and the second inverter based on a result of the temperature estimation by the temperature estimator;
An electric vehicle control device comprising:
[Appendix 2]
2. The electric vehicle control device according to claim 1, wherein the current command calculation circuit controls the current command values of the first inverter and the second inverter so that the temperature of the semiconductor switching elements of the second inverter does not exceed the temperature of the semiconductor switching elements of the first inverter.
[Appendix 3]
3. The electric vehicle control device according to claim 1, wherein the current command calculation circuit controls the current command values of the first inverter and the second inverter so that the temperature of a semiconductor switching element of the second inverter does not exceed a preset allowable value.
[Appendix 4]
The electric vehicle control device according to any one of appendix 1 to 3, wherein the temperature estimation unit is operated by a power supply of a gate drive circuit of a semiconductor switching element of the first inverter or the second inverter, and outputs a temperature estimation result to the current command calculation circuit via a signal isolator.
[Appendix 5]
5. The electric vehicle control device according to claim 4, wherein the temperature estimation unit estimates the temperature based on a detection result of a temperature sensor that detects temperatures of semiconductor switching elements of the first inverter and the second inverter.
[Appendix 6]
The first inverter and the second inverter are disposed in a cooling unit that takes in wind while the vehicle is running.
the first inverter is disposed at a rear of the vehicle in the traveling direction,
5. The electric vehicle control device according to claim 1, wherein the second inverter is disposed forward in the traveling direction of the vehicle.
[Appendix 7]
The electric vehicle control device described in Appendix 6, wherein the current command calculation circuit stops control of the current command value when a deviation between a detection result of a temperature sensor provided in the cooling unit and a temperature estimation result by the temperature estimation unit becomes equal to or greater than a preset threshold value.
[Appendix 8]
The electric vehicle control device described in Appendix 6, wherein the current command calculation circuit stops the first inverter and the second inverter when a deviation between a detection result of a temperature sensor provided in the cooling unit and a temperature estimation result by the temperature estimation unit becomes equal to or greater than a preset threshold value.

1...Electric vehicle control device, 2...Vehicle, 3...Train line, 4...Current collector, 5...Permanent magnet synchronous motor, 6...Railway, 11...Boost circuit, 12...Power conversion circuit, 13...Inverter device, 14...Main control circuit, 21...Resonant inverter, 22...Transformer, 23...Rectifier circuit, 24...Smoothing circuit, 31...First inverter, 32...Second inverter, 33...First temperature sensor, 34...Second temperature sensor, 35...Inverter control circuit, 41...Powered bogie, 42...Cooling unit, 51...First wheel, 52...Second wheel, 61...First direction, 62...Second direction, 71...First motor, 72...Second motor, 81...Storage section, 82...Air Intake, 91...first PWM controller, 92...second PWM controller, 93...first current controller, 94...second current controller, 95...current command calculation circuit, 96...temperature estimation unit, 101...current pattern generator, 102...constant output unit, 103...ratio adjuster, 104...subtractor, 105...adder, 106...first multiplier, 107...second multiplier, 111...isolated power supply circuit, 112...gate driver, 113...inverter main circuit, 121...temperature estimation unit power supply, 122...signal transmission unit, 123...signal isolation circuit, 131...clock generator, 132...comparator, 141...temperature sensor, 142...abnormality detection unit.

Claims (7)

a first motor that drives a first wheel of the vehicle;
a second motor that drives a second wheel that is disposed rearward of the first wheel in a traveling direction of the vehicle;
a first inverter that supplies a current to the first motor;
a second inverter disposed forward of the first inverter in the traveling direction of the vehicle and configured to supply a current to the second motor;
a temperature estimator that estimates temperatures of semiconductor switching elements of the first inverter and the second inverter;
a current command calculation circuit that controls current command values of the first inverter and the second inverter based on a result of the temperature estimation by the temperature estimator;
Equipped with
The current command calculation circuit controls the current command values of the first inverter and the second inverter so that the temperature of the semiconductor switching elements of the second inverter does not exceed the temperature of the semiconductor switching elements of the first inverter . 2. The electric vehicle control device according to claim 1, wherein the current command calculation circuit controls the current command values of the first inverter and the second inverter so that the temperature of a semiconductor switching element of the second inverter does not exceed a preset allowable value. 3. The electric vehicle control device according to claim 1, wherein the temperature estimation unit is operated by a power supply of a gate drive circuit of a semiconductor switching element of the first inverter or the second inverter , and outputs a temperature estimation result to the current command calculation circuit via a signal isolator. 4. The electric vehicle control device according to claim 3 , wherein the temperature estimation unit estimates the temperature based on a detection result of a temperature sensor that detects temperatures of semiconductor switching elements of the first inverter and the second inverter. The first inverter and the second inverter are disposed in a cooling unit that takes in wind while the vehicle is running.
the first inverter is disposed at a rear of the vehicle in the traveling direction,
The electric vehicle control device according to claim 1 , wherein the second inverter is disposed at a front of the vehicle in the traveling direction. a first motor that drives a first wheel of the vehicle;
a second motor that drives a second wheel that is disposed rearward of the first wheel in a traveling direction of the vehicle;
a first inverter that supplies a current to the first motor;
a second inverter disposed forward of the first inverter in the traveling direction of the vehicle and configured to supply a current to the second motor;
a temperature estimator that estimates temperatures of semiconductor switching elements of the first inverter and the second inverter;
a current command calculation circuit that controls current command values of the first inverter and the second inverter based on a result of the temperature estimation by the temperature estimator;
a cooling unit in which the first inverter and the second inverter are arranged and which takes in wind generated when the vehicle is traveling;
the first inverter is disposed at a rear of the vehicle in the traveling direction,
the second inverter is disposed at a front of the vehicle in the traveling direction,
The current command calculation circuit is an electric vehicle control device that stops control of the current command value when the deviation between the detection result of a temperature sensor provided in the cooling unit and the temperature estimation result by the temperature estimation unit becomes equal to or greater than a predetermined threshold value. a first motor that drives a first wheel of the vehicle;
a second motor that drives a second wheel that is disposed rearward of the first wheel in a traveling direction of the vehicle;
a first inverter that supplies a current to the first motor;
a second inverter disposed forward of the first inverter in the traveling direction of the vehicle and configured to supply a current to the second motor;
a temperature estimator that estimates temperatures of semiconductor switching elements of the first inverter and the second inverter;
a current command calculation circuit that controls current command values of the first inverter and the second inverter based on a result of the temperature estimation by the temperature estimator;
a cooling unit in which the first inverter and the second inverter are arranged and which takes in wind generated when the vehicle is traveling;
the first inverter is disposed at a rear of the vehicle in the traveling direction,
the second inverter is disposed at a front of the vehicle in the traveling direction,
The current command calculation circuit is an electric vehicle control device that stops the first inverter and the second inverter when the deviation between the detection result of a temperature sensor provided in the cooling unit and the temperature estimation result by the temperature estimation unit becomes equal to or greater than a predetermined threshold value.