Electric vehicle controller

1. An electric vehicle controller including an AC motor, the electric vehicle controller comprising:

a main circuit configured to convert a DC power supplied from a DC power source into an AC power and supply the AC power to the AC motor;

a vector control unit configured to generate a switching command to instruct a switching operation of the main circuit, thereby performing vector control of the AC motor;

a torque-command-value generating unit configured to generate a torque command value that is a command value of a torque that the AC motor is caused to output; and

a vector-control-command-value calculating unit configured to

calculate, from the torque command value, a first magnetic-flux command value for which a loss of the AC motor is minimized, and a second magnetic-flux command value that is a magnetic-flux command value when the AC motor is controlled in a one-pulse mode,

calculate a first total sum of losses of the AC motor and losses of the main circuit when the AC motor is controlled by the first magnetic-flux command value and a second total sum of losses of the AC motor and losses of the main circuit when the AC motor is controlled by the second magnetic-flux command value, and

output, to the vector control unit, a magnetic-flux command value corresponding to the smaller of the first and second total sum of losses.

2. An electric vehicle controller including an AC motor, the electric vehicle controller comprising:

a first main circuit configured to convert an AC power supplied from an AC power source into a DC power;

a converter control unit configured to generate a switching command to instruct a switching operation of the first main circuit;

a DC-power source unit configured to receive the DC power from the first main circuit;

a DC-voltage detecting unit configured to detect a voltage of the DC-power source unit;

a second main circuit configured to convert a DC power output from the DC-power source unit into a converted AC power and supply the converted AC power to the AC motor;

a vector control unit configured to generate a switching command to instruct a switching operation of the second main circuit, thereby performing vector control of the AC motor;

a torque-command-value generating unit configured to generate a torque command value that is a command value of a torque that the AC motor is caused to output; and

a vector-control-command-value calculating unit configured to

calculate, from the torque command value, a terminal-voltage amplitude of the AC motor when the AC motor is controlled by a magnetic-flux command value for which a loss of the AC motor is minimized,

select, based on calculated terminal-voltage amplitude and an upper limit value and a lower limit value that are previously decided by a characteristic of the first main circuit and that are related to an applied voltage of the DC-power source unit, a DC-voltage command value to command the voltage of the DC-power source unit, out of a DC-power-source-unit conversion value of the terminal-voltage amplitude, the upper limit value, and the lower limit value, and

output the selected DC-voltage command value to the converter control unit.

3. The electric vehicle controller according to claim 2 , wherein the vector-control-command-value calculating unit further calculates the magnetic-flux command value when the AC motor is controlled in a one-pulse mode and outputs the calculated magnetic-flux command value to the vector control unit.

4. The electric vehicle controller according to claim 2 , wherein characteristics of the first main circuit include a voltage condition of the AC power source and a circuit configuration of the first main circuit, and an insulating property and a withstand voltage property of the first main circuit.

5. An electric vehicle controller including an AC motor, the electric vehicle controller comprising:

a first main circuit configured to convert an AC power supplied from an AC power source into a DC power;

a converter control unit configured to generate a switching command to instruct a switching operation of the first main circuit;

a DC-power source unit to which a DC power output from the first main circuit is inputted;

a DC-voltage detecting unit that detects a voltage of the DC-power source unit;

a second main circuit that converts the DC power output from the DC-power source unit into a converted AC power and supplies the converted AC power to the AC motor;

a vector control unit that generates a switching command to instruct a switching operation of the second main circuit, thereby performing vector control of the AC motor;

a torque-command-value generating unit that generates a torque command value that is a command value of a torque that the AC motor is caused to output; and

a vector-control-command-value calculating unit configured to

calculate, from the torque command value, (i) a first magnetic-flux command value for which a loss of the AC motor is minimized, (ii) a terminal-voltage amplitude of the AC motor when the AC motor is controlled by the first magnetic-flux command value, and (iii) a second magnetic-flux command value when the AC motor is controlled in a one-pulse mode,

calculate a first total sum of losses of the AC motor and losses of the second main circuit when the AC motor is controlled by the first magnetic-flux command value and a second total sum of losses of the AC motor and losses of the second main circuit when the AC motor is controlled by the second magnetic-flux command value and output to the vector control unit a magnetic-flux command value corresponding to a total sum of smaller losses,

set a lower limit value that is previously decided by a characteristic of the first main circuit and that is related to an applied voltage of the DC-power source unit to a DC voltage command value to command the voltage of the DC-power source unit, and

output the DC-voltage command value to the vector control unit.

6. The electric vehicle controller according to claim 5 , wherein characteristics of the first main circuit include a voltage condition of the AC power source and a circuit configuration of the first main circuit, and an insulating property and a withstand voltage property of the first main circuit.

7. An electric vehicle controller including an AC motor, the electric vehicle controller comprising:

a main circuit configured to convert a DC power supplied from a DC power source into an AC power and supply the AC power to the AC motor;

a vector control unit configured to generate a switching command to instruct a switching operation of the main circuit, thereby performing vector control of the AC motor;

a torque-command-value generating unit configured to generate a torque command value that is a command value of a torque that the AC motor is caused to output and a notch command value received from an operation unit operated by a driver of the electric vehicle; and

a vector-control-command-value calculating unit including a table registered with a magnetic-flux command value corresponding to a total sum of smaller losses, previously calculated, according to the notch command value, based on (i) a first magnetic-flux command value for which a loss of the AC motor is minimized, (ii) a second magnetic-flux command value that is a magnetic-flux command value when the AC motor is controlled in a one-pulse mode, (iii) a first total sum of losses of the AC motor and losses of the main circuit when the AC motor is controlled by the first magnetic-flux command value, and (iii) a second total sum of losses of the AC motor and losses of the main circuit when the AC motor is controlled by the second magnetic-flux command value, wherein

the vector-control-command-value calculating unit selects from the table, according to the notch command value, the magnetic-flux command value to be output to the vector control unit.

8. An electric vehicle controller including an AC motor, the electric vehicle controller comprising:

a first main circuit configured to convert an AC power supplied from an AC power source into a DC power;

a converter control unit configured to generate a switching command to instruct a switching operation of the first main circuit;

a DC-power source unit configured to receive the DC power from the first main circuit;

a DC-voltage detecting unit configured to detect a voltage of the DC-power source unit;

a second main circuit configured to convert a DC power output from the DC-power source unit into a converted AC power and supply the converted AC power to the AC motor;

a vector control unit configured to generate a switching command to instruct a switching operation of the second main circuit, thereby performing vector control of the AC motor;

a torque-command-value generating unit configured to generate a notch command value received from an operation unit of a driver of the electric vehicle and a torque command value that is a command value of a torque that the AC motor is caused to output; and

a vector-control-command-value calculating unit including a table registered with a DC voltage command value that is used to command voltage of the DC-power source unit and that is previously calculated, according to the notch command value, based on (i) a terminal-voltage amplitude of the AC motor when being controlled by a magnetic-flux command value for which a loss of the AC motor is minimized and (ii) an upper limit value and a lower limit value that are previously decided by a characteristic of the first main circuit and that are related to an applied voltage of the DC-power source unit, wherein

the vector-control-command-value calculating unit selects, according to the notch command value, the DC-voltage command value to be output to the converter control unit from the table.

9. The electric vehicle controller according to claim 8 , wherein characteristics of the first main circuit include a voltage condition of the AC power source and a circuit configuration of the first main circuit, and an insulating property and a withstand voltage property of the first main circuit.