JP6498949B2 - Electric vehicle control device - Google Patents

Description

  Embodiments according to the present invention relate to an electric vehicle control apparatus.

  Conventionally, a control device that performs power conversion is used to operate a drive system such as a main motor (motor) of an electric vehicle. The control device converts the overhead line power into the power required for the drive system in order to rotate the wheels of the electric vehicle.

  Such a control device is provided with a cooler in order to dissipate heat generated by power conversion. The cooler is designed based on route information and an operation pattern on which the electric vehicle actually travels. For example, when there is a steep slope section or a section where power running and regeneration are frequently repeated on the travel route, the control device requires a large amount of power or causes a large power loss. Furthermore, in such a case, the electric vehicle may travel at a low speed. Therefore, the control device generates a lot of heat while the electric vehicle is traveling, and the cooling performance of the cooler (for example, the cooling fin or the cooling blower) may be deteriorated. Therefore, conventionally, the cooler has been designed in advance in a large size so as to exhibit high cooling performance adapted to a specific section such as a steep slope.

  However, a specific section such as a steep section is a part of the entire travel route. Therefore, in other normal sections (for example, flat sections), the cooling performance of the large cooler is often excessive. Further, increasing the size of the cooler for a specific section such as a steep slope section leads to an increase in the size of the control device itself, and also increases the cost of the control device.

JP 2014-239576 A

  To provide a small and low-cost electric vehicle control apparatus having appropriate cooling performance.

The electric vehicle control device according to the present embodiment is an electric vehicle control device that converts electric power from a power source and supplies the electric power to a load of the electric vehicle. The electric vehicle control device converts electric power from the power source to the electric vehicle load. a VVVF inverter for supplying power, and a cooling unit for cooling the VVVF inverter, and a control section for PWM controlling the VVVF inverter, when the electric vehicle enters the predetermined section of the travel route, the control unit, PWM Change the control carrier frequency.

A block diagram showing an example of composition of electric car control device 1 grade by a 1st embodiment. The graph which shows the speed St of a certain electric vehicle, and the temperature T20 of the semiconductor switching element of the inverter 20. FIG. The flowchart which shows an example of operation | movement of the control apparatus 1 by this embodiment.

  Embodiments according to the present invention will be described below with reference to the drawings. This embodiment does not limit the present invention.

  FIG. 1 is a block diagram illustrating an example of the configuration of the electric vehicle control device 1 according to the present embodiment. An electric vehicle control device (hereinafter also simply referred to as a control device) 1 is a device used for electric power control of a vehicle of an electric vehicle such as a railway, and is disposed under the floor or roof of the vehicle.

  The pantograph PG is in electrical contact with the overhead line 2 as a power source, and supplies power from the overhead line to the control device 1 or supplies regenerative power to the overhead line 2. The electric power from the pantograph PG is supplied to the control device 1 via a circuit breaker (VCB (Vacuum Circuit Breaker)) and the transformer 4. The control device 1 converts the electric power from the transformer 4 and supplies it to the motor (load) 3.

  The motor 3 drives the wheels of the electric vehicle to run the electric vehicle. The motor 3 is, for example, a three-phase AC motor (three-phase induction motor), and is a permanent magnet synchronous motor (PMSM) using a ferromagnetic material such as a neodymium magnet. More specifically, the three-phase AC power from the inverter 20 is supplied to the motor 3, and the motor 3 drives the electric vehicle. The motor 3 rotates a rotor (not shown), thereby rotating the wheel axle of the electric vehicle via a gear or the like.

  The train control monitoring device 5 is provided in common for trains composed of a plurality of electric vehicles, receives information from the outside and information of each vehicle, and transmits the information to the control device 1 of each vehicle. For example, the train control monitoring device 5 includes an external ATS (Automatic Train Stop), information from an ATC (Automatic Train Control), a notch command from the cab, position information from the position detection receivers 90 and 91, and others. Is received and transmitted to the control device 1 of each vehicle. Thereby, each vehicle can obtain external information, failure information of other vehicles, position information of the own vehicle, and the like. Such information may be displayed on the display unit 7 of the cab.

  The display part 7 is provided in the cab of an electric vehicle, and displays various information.

  The control device 1 includes a converter 10, an inverter 20, a controller 30, a circuit breaker 40, heat radiation fins 50 and 51, a contactor 70, temperature sensors 80, 81 and 83, and position detection receivers 23 and 24. And.

  The circuit breaker 40 includes a main power switch, a high-speed circuit breaker that cuts off power when a serious failure occurs, and a circuit breaker that cuts off power when the notch is turned off.

  Converter 10 converts AC power from overhead line 2 into DC power. The converter 10 is, for example, a PWM (Pulse Width Modulation) converter, a semiconductor switching element such as a plurality of IGBTs (Insulated Gate Bipolar Transistors) and GTO (Gate Turn Off Thyristor), or a diode connected in parallel to the semiconductor switching elements. Or it is comprised with semiconductor elements, such as a clamp diode. Converter 10 receives control of controller 30 and performs switching control (on / off control) of the semiconductor switching element to convert AC power into DC power.

  Inverter 20 converts the DC power from converter 10 into AC power, and supplies the AC power to motor 3 via contactor 70. For example, the inverter 20 converts DC power into three-phase AC power. The inverter 20 is, for example, a PWM-controlled VVVF (Variable Voltage Variable Frequency) inverter, and a plurality of semiconductor switching elements such as IGBTs and GTOs, and semiconductor elements such as diodes or clamp diodes connected in parallel to the semiconductor switching elements. It consists of The inverter 20 converts the DC power into AC power by controlling the semiconductor switching element (ON / OFF control) under the control of the controller 30.

  The radiating fins 50 and 51 are provided in the converter 10 and the inverter 20, respectively. Semiconductor switching elements such as IGBTs and GTOs used for the converter 10 and the inverter 20 generate a lot of loss (heat) due to switching. For this reason, the control apparatus 1 needs to cool using a cooling device. In this embodiment, the radiation fins 50 and 51 are used as an example of a cooler. The heat radiation fins 50 and 51 extend downward from the bottom surfaces of the converter 10 and the inverter 20 and are cooled by the traveling wind of the electric vehicle. Thereby, the radiation fins 50 and 51 can efficiently dissipate the heat of the switching loss of the converter 10 and the inverter 20 that occurs during the traveling of the electric vehicle. Instead of the heat radiating fins, a heat radiating blower may be provided in the converter 10 and the inverter 20.

  The temperature sensor 80 is arranged in the converter 10 or in the vicinity of the converter 10 and detects the temperature of the semiconductor switching element of the converter 10. The temperature sensor 81 is disposed in the inverter 20 or in the vicinity of the inverter 20, and detects the temperature of the semiconductor switching element of the inverter 20. The temperature sensor 82 is disposed outside the electric vehicle, detects the outside air temperature, and transmits the outside air temperature to the control device 1. The temperature sensor 83 is disposed in the housing of the control device 1 and detects the temperature inside the housing of the control device 1.

  The contactor 70 is an electromagnetic switch that electrically connects or opens the motor 3 and the inverter 20. For example, the contactor 70 may be a motor open contactor (MCOK).

  The position detection receivers 90 and 91 are, for example, a vehicle upper piece that communicates with a ground piece grounded on the ground to obtain position information (for example, kilometer information) or a GPS (Global Positioning System) receiver. In this way, the position of the host vehicle can be detected.

  The controller 30 includes a control signal from the cab (for example, a notch command), the number of revolutions of the motor 3, train speed information from the train control monitoring device 5, boarding rate information, temperature information from the temperature sensors 80 to 83, other Various information such as vehicle failure information, a current value supplied to the motor 3, and an overhead wire voltage value is received. Based on the information, the controller 30 controls switching of the converter 10 and the inverter 20 and controls connection / release of the contactor 70.

  Further, the controller 30 is based on at least one parameter of any one of the position of the electric car, the temperature of the converter 10 or the inverter 20, the temperature inside the housing of the control device 1, the outside air temperature, or the train boarding rate. Then, the PWM control carrier frequency of the converter 10 or the inverter 20, the number of pulses of the PWM control carrier, or the output power of the converter 10 or the inverter 20 is changed. The controller 30 may be provided inside the control device 1 or may be provided outside the controller 30.

  For example, when the position of the electric vehicle is used as a parameter, the converter 10 and the inverter 20 supply a large amount of electric power to the motor 3 and the switching loss when the electric vehicle reaches a gradient section or a section where power running / regeneration is repeated. Also grows. In this case, a large amount of heat is generated in converter 10 and inverter 20. In addition, when the travel section is steep, the speed of the electric vehicle may be relatively slow although the power consumption is large. For this reason, the cooling performance of the radiation fins 50 and 51 is lowered.

  The converter 10 normally travels by receiving a constant voltage from the overhead wire 2. Thus, the converter 10 generates a lot of heat during high speed travel that requires a relatively large current. On the other hand, in low speed traveling, the converter 10 does not generate much heat, so that even if the cooling performance is lowered, it is allowed to some extent. On the other hand, the inverter 20 travels with a constant torque during low-speed traveling and travels with constant power during high-speed traveling. Therefore, the inverter 20 generates a relatively large amount of heat even when traveling at a low speed. Therefore, the inverter 20 requires high cooling performance even at low speeds. Considering such a situation, the cooling performance of the radiating fins 51 provided in the inverter 20 is more important than the cooling performance of the radiating fins 50 provided in the converter 10. Therefore, hereinafter, the controller 30 will be described as changing the PWM control of the inverter 20. However, the controller 30 may change the PWM control of one or both of the converter 10 and the inverter 20.

  FIG. 2 is a graph showing the speed St of a certain electric vehicle and the temperature T20 of the semiconductor switching element of the inverter 20. The horizontal axis represents time, the right vertical axis represents the electric vehicle speed St, and the left vertical axis represents the temperature T20 of the semiconductor switching element of the inverter 20. A section indicated by Ls indicates a gradient section. A section other than Ls indicates a flat normal section. It can be seen that when the electric vehicle reaches the gradient section Ls, the speed St of the electric vehicle increases slowly, and accordingly, the temperature T20 of the semiconductor switching element of the inverter 20 rapidly increases. This is because if the speed St of the electric vehicle is slow, the cooling performance of the radiating fins 51 decreases. Such a rise in the temperature T20 of the semiconductor switching element of the inverter 20 causes the semiconductor switching element of the inverter 20 to be damaged.

  Assuming the gradient section Ls or the section in which power running / regeneration is repeated, if the radiation fins 51 are designed in advance to have a large cooling performance, the size of the radiation fins 51 becomes very large. For example, the radiating fins 51 are typically used for the allowable temperature of the semiconductor switching element of the inverter 20, the allowable temperature in the housing of the control device 1, the allowable temperature of the outside air, the maximum slope of the traveling section gradient, the traction of other vehicles, Designed assuming the worst case. In this case, for example, assuming that the electric vehicle travels in a steep slope section while pulling another vehicle at a time when the outside air temperature is high, the radiating fins 51 are designed to be very large in order to enhance the cooling performance. This increases the size of the control device 1 and increases the cost.

  Therefore, in the control device 1 according to the present embodiment, the controller 30 performs PWM control of the inverter 20 using as a trigger the condition that the position of the electric vehicle has entered a predetermined section (for example, a gradient section or a section in which powering / regeneration is repeated). change. Thereby, the control apparatus 1 can switch the traveling pattern of the electric vehicle based on the position of the electric vehicle. For example, when the position of the electric vehicle enters a predetermined section, the controller 30 reduces the PMW control carrier frequency of the inverter 20 or reduces the number of PWM control carrier pulses. Thereby, since the switching frequency of the inverter 20 falls, a switching loss falls and the generation amount of heat falls. As a result, the radiating fins 51 are compared without assuming the worst case such as the traveling section, the temperature of the semiconductor switching element, the temperature in the housing of the control device 1, the temperature of the outside air, the gradient of the traveling section, and the traction of other vehicles. Even if it is designed to be small, excessive heat generation in the inverter 20 can be suppressed and the inverter 20 can be protected in the gradient section or the section where power running / regeneration is repeated. Since the radiating fins 51 are relatively small, the size of the control device 1 itself is reduced, and the cost is also reduced.

  When the carrier frequency of PWM control or the number of carrier pulses is decreased, the voltage waveform of the three-phase AC output from the inverter 20 becomes rough, and the deviation from the desired modulation wave (centered on a smooth sine wave) Unevenness) becomes large. However, since the output power itself from the inverter 20 hardly changes, the torque of the motor 3 hardly changes. Therefore, according to this embodiment, the switching loss of the inverter 20 can be reduced without reducing the speed (running performance) of the electric vehicle.

  The controller 30 may reduce the output power itself of the inverter 20 instead of reducing the carrier frequency or the number of carrier pulses in PWM control. In this case, it is necessary to allow the electric vehicle speed (running performance) to decrease to some extent.

  In the above example, “position of electric vehicle” is used as a parameter for changing the PWM control of the inverter 20, but as other parameters, the temperature of the semiconductor switching element of the inverter 20, the temperature inside the housing of the control device 1, The outside air temperature, the state of the electric vehicle control device (stop / start state) of other vehicles in the train, the electric vehicle boarding rate, or the like may be used.

  In the above example, the condition for changing the PWM control of the inverter 20 is “the position of the electric vehicle has entered a predetermined section”. However, the changing condition of the PWM control may be other conditions depending on the parameters. For example, the conditions for changing the PWM control of the inverter 20 are that the temperature of the semiconductor switching element of the inverter 20 is equal to or higher than a predetermined temperature, the temperature inside the housing of the control device 1 is equal to or higher than the predetermined temperature, The temperature of the vehicle has reached a predetermined temperature or higher, the electric vehicle control device of another vehicle in the train is in a stopped state, or the electric vehicle boarding rate has reached a predetermined value or higher. Further, two or more of these parameters and conditions may be used in combination.

  Although the above configuration shows the case where the power supplied via the pantograph PG is alternating current, the supplied power may be direct current. In this case, the control device 1 is configured without the converter 10.

  Next, the operation of the control device 1 according to the present embodiment will be described.

  FIG. 3 is a flowchart showing an example of the operation of the control device 1 according to the present embodiment. First, the electric vehicle normally travels in a relatively flat section (S10). The controller 30 periodically determines whether the parameter meets a predetermined condition (S20). For example, the position of the electric vehicle as a parameter can be obtained from the position detection receiver 91 directly from the position detection power receiver 90 or via the train control monitoring device 5. The temperature of the converter 10 or the inverter 20, the temperature inside the housing of the control device 1, and the outside air temperature can be obtained from the temperature sensors 80 to 83. The state of the electric vehicle control device of another vehicle can be obtained from the other vehicle via the train control monitoring device 5. The boarding rate of the train can be obtained from a weight sensor (not shown) or the like.

  When the parameter does not satisfy the predetermined condition (NO in S20), the controller 30 does not change the PWM control carrier of the inverter 20 and does not change the output power of the inverter 20. Therefore, the electric car continues normal running (S10).

  When the parameter satisfies the predetermined condition (YES in S20), the controller 30 decreases the PWM control carrier frequency of the inverter 20 or decreases the number of PWM control carrier pulses of the inverter 20 (S30).

  For example, when the electric vehicle enters a gradient section, the controller 30 needs to increase the output power of the inverter 20. On the other hand, the controller 30 reduces the PWM control carrier frequency of the converter 10 or the inverter 20 or reduces the number of PWM control carrier pulses of the inverter 20. Thereby, the switching loss (heat generation) of the inverter 20 can be suppressed while increasing the output power of the inverter 20.

  When entering a section in which repetition of power running and regeneration is entered, the controller 30 reduces the carrier frequency of PWM control of the inverter 20 or reduces the number of pulses of the carrier of PWM control of the inverter 20. Thereby, the switching loss (heat generation) of the inverter 20 can be suppressed. When entering a section in which repeated power running and regeneration are entered, the controller 30 may suppress the heat generation of the inverter 20 by reducing the output power of the inverter 20.

  In addition, for example, when the temperature of the semiconductor switching element of the inverter 20 becomes equal to or higher than a predetermined temperature, when the temperature inside the housing of the control device 1 becomes equal to or higher than the predetermined temperature, or when the outside air temperature becomes equal to or higher than the predetermined temperature. In this case, the controller 30 reduces the carrier frequency of PWM control of the inverter 20 or reduces the number of pulses of the carrier of PWM control of the inverter 20. Thereby, the switching loss (heat generation) of the inverter 20 can be suppressed. In these cases, the controller 30 may suppress the heat generation of the inverter 20 by reducing the output power of the inverter 20.

  Furthermore, for example, when the electric vehicle control device of another vehicle in the train is in a stopped state, or when the electric vehicle boarding rate exceeds a predetermined value, the controller 30 increases the output power of the inverter 20. There is a need. When the electric vehicle control device of another vehicle is stopped, it is necessary to increase the output power in order for the control device 1 of the own vehicle to compensate for the electric vehicle control device of the other vehicle. Therefore, the controller 30 suppresses the switching loss (heat generation) of the inverter 20 by decreasing the PWM control carrier frequency of the inverter 20 or by decreasing the number of PWM control carriers of the inverter 20.

  When the carrier frequency of PWM control is lowered or the number of pulses of the carrier of PWM control is reduced (when the running pattern is changed), the controller 30 indicates to the driver that the running pattern is changed. The change is displayed on the display 7 of the cab (S40).

  Thereafter, when the parameter no longer satisfies the predetermined condition (NO in S20), the controller 30 returns the traveling pattern to the original, and the electric vehicle returns to the normal traveling (S10).

  As described above, the control device 1 according to the present embodiment lowers the carrier frequency or the number of pulses of the PWM control of the inverter 20 by using a parameter such as the position of the electric vehicle as a trigger. Thereby, since the switching frequency of the inverter 20 falls, a switching loss falls and the generation amount of heat falls.

  Alternatively, the control device 1 reduces the output power of the inverter 20. Thereby, the calorific value of the inverter 20 is reduced.

  As a result, even if the heat radiating fins 51 are designed to be relatively small assuming a normal traveling section (such as a flat section), the control device 1 suppresses excessive heat generation in the inverter 20 by changing the traveling pattern. be able to. Accordingly, the radiating fins 51 are relatively arranged without assuming the worst case such as the traveling section, the temperature of the semiconductor switching element, the temperature in the casing of the control device 1, the temperature of the outside air, the gradient of the traveling section, and the traction of other vehicles. It can be designed to be small. Thereby, the magnitude | size of control apparatus 1 itself can become small, and cost can be reduced.

  Although the inverter 20 and the heat radiating fins 51 have been described above, the same can be said for the converter 10 and the heat radiating fins 50 as described above.

  In this embodiment, you may combine several conditions among the said conditions. For example, the controller 30 may change the travel pattern when the electric vehicle enters a predetermined section in step S20 and the boarding rate of the electric vehicle is greater than or equal to a predetermined value.

  In this embodiment, in step S30, the controller 30 uses both the change of the PWM control carrier frequency or the number of carrier pulses of the converter 10 or the inverter 20 and the change of the output power of the converter 10 or the inverter 20. You may change the running pattern. For example, in step S30, the controller 30 may reduce the carrier frequency or the number of carrier pulses for PWM control and reduce the output power of the converter 10 or the inverter 20. Even if it does in this way, the effect of this embodiment is not lost.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Electric vehicle control apparatus, 2 ... Overhead wire, 3 ... Motor, 5 ... Train control monitoring apparatus, 7 ... Display part, 10 ... Converter, 20 ... Inverter, 30 ... Controller, 40 ... Circuit breaker, 50, 51 ... Radiation fin, 70 ... Contactor, 80-83 ... Temperature sensor, 23, 24 ... Position detection receiver

Claims (4)

An electrical vehicle control device for supplying electric power to the electric vehicle load to convert the power from the power source, to convert the power from the power supply, VVVF supplies electric power to a load of the electric vehicle (Variable Voltage Variable Frequency) inverter ,
A cooling unit for cooling the VVVF inverter ;
A controller for PWM controlling the VVVF inverter ,
When the electric vehicle has entered a predetermined section of the travel route, the controller changes the carrier frequency of the PWM control, the electric vehicle control device. When the electric vehicle has entered a predetermined section of the travel route, the control unit, the Ru lowers the carrier frequency of the PWM control, the electric vehicle control device according to claim 1. It enters the predetermined section of the electric vehicle is traveling route, and when the electric vehicle occupancy is equal to or greater than a predetermined value, the control unit, characterized in that, to lower the carrier frequency of the PWM control The electric vehicle control device according to claim 1 . When the electric vehicle has entered a predetermined section of the travel route, the controller changes the carrier frequency of the PWM control and reduces the output power of the VVVF inverter, claims 1 4. The electric vehicle control device according to any one of 3 .

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