Patent ID: 8179068

Claim:
A variable-flux motor drive system having an inverter for driving a variable-flux motor that employs a fixed magnet and a variable magnet, comprising: a torque command generate unit to generate a torque command for the variable-flux motor; a variable flux control unit to change flux according to a magnetizing current from the inverter and magnetize the variable magnet; a switch to pass D- and Q-axis current references based on the torque command from the torque command generate unit or D- and Q-axis magnetizing current commands from the variable flux control unit; a magnetization request generate unit to generate, if predetermined conditions are met, a request to the variable flux control unit for magnetizing the variable magnet; and a gate command generate unit to generate a gate command for controlling the inverter according to the torque-command-based D- and Q-axis current references or the D- and Q-axis magnetizing current commands from the switch.