Control system and controlling method for motor drive four wheel drive vehicle

A control system for controlling a vehicle which has an engine for driving at least one of wheels thereof and a motor for driving at least one of the rest of the wheels thereof, the control system comprising:

• a motor generator configured to be driven by the engine for generating first alternating-current power at a first voltage;
• an inverter which converts the first alternating-current power to second power at a second voltage lower than the first voltage or to third direct-current power at a third voltage;
• and
• a battery to be charged with the second power supplied from the inverter,
• wherein the motor is supplied with the third direct-current power at the third voltage obtained from the first alternating-current power, and wherein
• the inverter is supplied with fourth power at a fourth voltage discharged from the battery and converts the fourth power to fifth power at a fifth voltage, and
• the motor generator is supplied with the fifth power and generates driving force for starting the engine.

A control system for controlling a vehicle which has an engine for driving at least one of wheels thereof and a motor for driving at least one of the rest of the wheels thereof, the control system comprising:

• a motor generator configured to be driven by the engine for generating first alternating-current power at a first voltage;
• an inverter which converts the first alternating-current power to second power at a second voltage lower than the first voltage or to third direct-current power at a third voltage;
• a battery to be charged with the second power supplied from the inverter;
• a first switch for changing electrical connection between the inverter and the battery;
• and
• a second switch for changing electrical connection between the inverter and the motor, wherein the motor is supplied with the third direct-current power at the third voltage obtained from the first alternating-current power, and wherein,
• when starting the engine, the first switch is closed and the second switch is opened, so that electricity can be supplied from the battery to the inverter,
• when charging the battery, the first switch is closed and the second switch is opened, so that electricity can be supplied from the inverter to the battery, and
• when driving the motor, the first switch is opened and the second switch is closed, so that electricity can be supplied from the inverter to the motor.

A method of controlling a vehicle which has an engine for driving at least one of wheels thereof and a motor for driving at least one of the rest of the wheels thereof, the method comprising:

• converting first alternating-current power at a first voltage generated by the motor generator to second direct-current power at a second voltage lower than the first voltage, supplying the second direct-current power to a battery for charging the battery;
• rectifying the first alternating-current power generated by the motor generator to obtain third direct-current power at a third voltage, supplying the third direct-current power to the motor for driving the motor;
• and
• converting fourth electric power at a fourth voltage discharged from a battery to fifth alternating-current power at a fifth voltage, supplying the fifth alternating-current power to a motor generator, starting the engine with driving force of the motor generator.