Patent ID: 9041325
Filing Date: 2015-05-26
Classification: H02P

Abstract:
1. A control device for an alternating current motor comprising: a current distributor that computes a component that contributes to a mechanical output of the alternating current motor as a δ-axis current command and a component that does not contribute to the mechanical output as a γ-axis current command, based on a torque command; a converter that converts a detected value of current flowing into the alternating current motor into a δ-axis component and a γ-axis component by using a control phase; a current controller that performs a control in such a manner that the δ-axis current command and the γ-axis current command are respectively identical with the δ-axis component current and the γ-axis component current flowing into the alternating current motor; a voltage drop calculator that calculates a voltage drop amount of inductance and wirewound resistance of the alternating current motor; a voltage commander that outputs a voltage command for the alternating current motor on the basis of an output of the current controller and an output of the voltage drop calculator; a phase estimator that computes at least one of a phase at which a γ-axis component of an addition amount of the output of the current controller and a voltage drop amount of the inductance becomes zero and a phase at which a δ-axis component obtained by integrating the addition amount becomes zero and outputs the computed phase as the control phase; and an inverter circuit that applies a voltage based on the voltage command to the alternating current motor.