Patent ID: 8278855
Filing Date: 2012-10-02
Classification: H02P

Abstract:
1. A controller of a motor comprising: a voltage-command generating unit that generates a pulse-width modulation signal to control a switching element provided in an inverter, to the inverter connected to a direct-current power source and outputting a three-phase alternating current of an arbitrary frequency and an arbitrary voltage to an alternating-current motor; and a current-command generating unit that generates and outputs a current command to cause the alternating-current motor to generate torque based on an input torque command, wherein the current-command generating unit is configured to output the current-command that is calculated based on a relationship between the torque command and a state quantity of the alternating-current motor, to maintain a terminal voltage of the alternating-current motor to a maximum value that can be generated under the direct-current power source, and to output a current command adjusted to maintain or decrease a loss of the inverter under a predetermined condition in which the loss of the inverter increases or estimated to increase.