Propulsion control apparatus for electric vehicle

• US 8,615,341 B2
• Filed: 10/23/2008
• Issued: 12/24/2013
• Est. Priority Date: 10/23/2008
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Kitanaka, Hidetoshi
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): Dunn, Alex C
• Application Number:
  US13/062,808
• Publication Number:
  US 20110166736A1
• Time in Patent Office: 1,888 Days
• Field of Search: 701/22
• US Class Current: 701/22
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/12 Methods and devices for control or regulation
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/02 characterised by the form of the current used in the control circuit
• CPC Class Codes: B60L 15/08 using pulses
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/527 Voltage
• CPC Class Codes: B60L 2250/12 by confirmation, e.g. of the input
• CPC Class Codes: B60L 2260/165 of converters
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/52 characterised by DC-motors
• CPC Class Codes: B60L 50/53 in combination with an external power supply, e.g. from overhead contact lines
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 9/00 Electric propulsion with power supply external to the vehicle electric propulsion for monorail vehicles, suspension vehicles or rack railways B60L13/00; in combination with batteries or fuel cells within the vehicle B60L50/53
• CPC Class Codes: B60L 9/04 : fed from dc supply lines
• CPC Class Codes: B60L 9/18 : fed from dc supply lines
• CPC Class Codes: B60L 9/22 : polyphase motors
• CPC Class Codes: H02M 3/1588 : comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: H02M 7/53871 : with automatic control of output voltage or current
• CPC Class Codes: H02P 2209/09 : PWM with fixed limited number of pulses per period
• CPC Class Codes: H02P 2209/095 : One pulse per half period
• CPC Class Codes: H02P 2209/13 : Different type of waveforms depending on the mode of operation
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles

Abstract

A propulsion control apparatus for an electric vehicle includes an inverter that converts a direct-current voltage into an alternating-current voltage, a power storage element, and a DCDC converter connected to the power storage element. The control apparatus further includes a circuit selector unit that selects any one of power supplied from an external power supply via a power collecting device and power supplied from the power storage element and outputs it to the inverter. A linkage control unit controls at least the DCDC converter and the circuit selector unit in a linked manner, in which the linkage control unit inputs control signals at least to the DCDC converter and the circuit selector unit and controls them in a linked manner, in accordance with each of a case where the electric vehicle travels by receiving power from the external power supply and a case where the electric vehicle travels by power from the power storage element.

Claims

1. A propulsion control apparatus for an electric vehicle that includes an inverter that converts a direct-current voltage into an alternating-current voltage, a power storage element, and a DCDC converter connected to the power storage element, comprising:

a circuit selector unit that selects any one of power supplied from an external power supply via a power collecting device and power supplied from the power storage element and outputs the supplied power to the inverter,

wherein the inverter is configured to;

operate in a plurality of pulse modes, wherein each pulse mode defines a different number of pulses included in a half cycle of an output-voltage fundamental wave of the inverter, and

perform a predetermined operation of changing the operating pulse mode to a pulse mode that has a predetermined number of pulses or less included in the half cycle, in accordance with a speed of the electric vehicle, and

wherein the predetermined operation of changing the operating pulse mode is performe at a lower speed when the electric vehicle travels by power from the power storage element than when the electric vehicle travels by receiving power from the external power supply.

2. The propulsion control apparatus for the electric vehicle according to claim 1, further comprising a linkage control unit that outputs, in accordance with each of the case where the electric vehicle travels by receiving power from the external power supply and the case where the electric vehicle travels by power from the power storage element, a control signal to the DCDC converter and the circuit selector unit and controls at least the DCDC converter and the circuit selector unit in a linked manner.

3. The propulsion control apparatus for the electric vehicle according to claim 1, wherein

a voltage between terminals of the power storage element is a value that is adjusted such that the inverter is operable in a one-pulse mode at an operating speed when travelling by power from the power storage element.

4. The propulsion control apparatus for the electric vehicle according to claim 1, wherein a voltage value at terminals of the power storage element is a value that is 20 to 50% of a rated voltage of the external power supply.

5. The propulsion control apparatus for the electric vehicle according to claim 1, wherein the predetermined number is one.

6. The propulsion control apparatus for the electric vehicle according to claim 1, further comprising an auxiliary power device that supplies power to a load mounted on the electric vehicle, wherein

the DCDC converter, when it becomes unable to receive power from the external power supply, boosts a voltage from the power storage element approximately to a voltage that the auxiliary power device normally receives from the external power supply and supplies it to the auxiliary power device.

7. The propulsion control apparatus for the electric vehicle according to claim 1, further comprising a power-collecting-state detecting unit that detects a connection state between the external power supply and the power collecting device, wherein

the DCDC converter performs a boost operation under a condition that the power-collecting-state detecting unit detects that a connection between the external power supply and the power collecting device is disconnected.

8. The propulsion control apparatus for the electric vehicle according to claim 1, further comprising an open/close unit that is provided between connection portions, to which the auxiliary power device and the DCDC converter are connected, and the power collecting device and separates the auxiliary power device and the DCDC converter from the power collecting device, wherein

the DCDC converter performs a boost operation under a condition that the open/close unit is opened.

9. The propulsion control apparatus for the electric vehicle according to claim 2, wherein

the linkage control unit,

in a case where it is determined that travelling of the electric vehicle by receiving power from the external power supply is possible, controls the circuit selector unit such that the inverter is directly connected to the external power supply and controls such that the DCDC converter performs an operation of charging the power storage element by power from the external power supply, and

in a case where it is determined that travelling of the electric vehicle by receiving power from the external power supply is impossible, controls the circuit selector unit such that the inverter is directly connected to the power storage element and controls such that the DCDC converter performs an operation of supplying power from the power storage element to an auxiliary power device that supplies power to a load mounted on the electric vehicle.

10. The propulsion control apparatus for the electric vehicle according to claim 2, wherein

a configuration is such that the control signal from the linkage control unit is output to an air conditioner of the electric vehicle, which is in a power feeding range of the auxiliary power device, and

the linkage control unit, when the electric vehicle travels by power from the power storage element, stops the air conditioner by outputting a stop command to the air conditioner.

11. The propulsion control apparatus for the electric vehicle according to claim 2, wherein

a configuration is such that the control signal from the linkage control unit is output to an air conditioner mounted on the electric vehicle, which is in a power feeding range of the auxiliary power device, and

the linkage control unit, when the electric vehicle travels by power from the power storage element, outputs a stop command for a refrigerant pressing compressor in the air conditioner and causes to continue an operation of a blast fan mounted on the electric vehicle.

12. The propulsion control apparatus for the electric vehicle according to claim 1, wherein

the DCDC converter includes an input filter circuit that includes a reactor and a filter capacitor that are connected to the external power supply, and a switching circuit that converts a direct-current voltage of the filter capacitor into an arbitrary direct-current voltage and outputs it, and

the switching circuit, when it is formed by an upper-arm-side switching element and a lower-arm-side switching element that are connected to the filter capacitor in parallel and is configured such that a reactor is connected to a connection point of the upper-arm-side switching element and the lower-arm-side switching element, has a voltage control mode of controlling a filter capacitor voltage of the DCDC converter to a predetermined value and a current control mode of controlling a reactor current of the DCDC converter to a predetermined value.

13. The propulsion control apparatus for the electric vehicle according to claim 12, wherein the DCDC converter operates while switching the control mode between the case where the electric vehicle travels by receiving power from the external power supply and the case where the electric vehicle travels by power from the power storage element.

14. The propulsion control apparatus for the electric vehicle according to claim 12, wherein the DCDC converter controls a voltage of the filter capacitor to be a value near an allowable lower limit of an input voltage of the auxiliary power device.

15. The propulsion control apparatus for the electric vehicle according to claim 1, wherein the DCDC converter has a target value concerning a stored electric energy of the power storage element, controls the stored electric energy to be the target value by performing charging and discharging on the power storage element, and changes the target value of the stored electric energy at least in accordance with time.

16. The propulsion control apparatus for the electric vehicle according to claim 2, wherein the DCDC converter has a target value concerning a stored electric energy of the power storage element, controls the stored electric energy to be the target value by performing charging and discharging on the power storage element, and changes the target value of the stored electric energy in accordance with the control signal from the linkage control unit.

17. The propulsion control apparatus for the electric vehicle according to claim 1, wherein the DCDC converter has a target value concerning a stored electric energy of the power storage element, controls the stored electric energy to be the target value by performing charging and discharging on the power storage element, and lowers the target value of the stored electric energy in accordance with an operation state of the inverter.

18. The propulsion control apparatus for the electric vehicle according to claim 6, wherein an output capacity of the DCDC converter is equal to or less than an output capacity of the auxiliary power device.

19. The propulsion control apparatus for the electric vehicle according to claim 2, wherein

the inverter at least includes an input-voltage monitoring unit that monitors an input voltage of the inverter and a protection operation unit that, when the input voltage falls outside a predetermined range, stops the inverter, and

the input-voltage monitoring unit switches the predetermined range for the input voltage between the case where the electric vehicle travels by receiving power from the external power supply and the case where the electric vehicle travels by power from the power storage element.

20. The propulsion control apparatus for the electric vehicle according to claim 1, wherein the inverter performs a predetermined operation of changing an output voltage of the inverter in accordance with a temperature of a semiconductor switching element included in the inverter.

21. The propulsion control apparatus for the electric vehicle according to claim 20, wherein the inverter, when the temperature of the semiconductor switching element included in the inverter is a predetermined value or more, performs a predetermined operation of increasing the output voltage of the inverter.

22. The propulsion control apparatus for the electric vehicle according to claim 21, wherein the inverter, when the temperature of the semiconductor switching element included in the inverter is the predetermined value or more, performs a predetermined operation of increasing the output voltage of the inverter until starting a switching operation in a one-pulse mode.

23. The propulsion control apparatus for the electric vehicle according to claim 20, wherein the predetermined operation is to increase an excitation current of an electric motor that is a load of the inverter.

24. The propulsion control apparatus for the electric vehicle according to claim 12, wherein the DCDC converter switches between the voltage control mode and the current control mode in accordance with the control signal from the linkage control unit.

25. The propulsion control apparatus for the electric vehicle according to claim 19, wherein the inverter switches the predetermined range for the input voltage in accordance with the control signal from the linkage control unit.

26. The propulsion control apparatus for the electric vehicle according to claim 1, wherein the DCDC converter has a target value concerning a stored electric energy of the power storage element, controls the stored electric energy to be the target value by performing charging and discharging on the power storage element, and changes the target value of the stored electric energy in accordance with an external control signal.