Patent ID: 9093936
Filing Date: 2015-07-28
Classification: H02N,H02P

Abstract:
1. An apparatus for controlling a three-phase AC motor to which a voltage controlled by an inverter is applied, the control apparatus comprising: a first current receiver configured to receive a first current detection value from a first current sensor provided to a first phase of the AC motor; a second current receiver configured to receive a second current detection value from a second current sensor provided to a second phase of the AC motor, the second phase being different from the first phase; a rotation angle receiver configured to receive a rotation angle detection value from a rotation angle sensor that detects a rotation angle of the AC motor; a two-phase control current value calculator configured to calculate a two-phase control current value based on the first current detection value, the second current detection value, and the rotation angle detection value; a one-phase control current value calculator configured to calculate a one-phase control current value based on the first current detection value and the rotation angle detection value; a rotation speed calculator configured to calculate a rotation speed of the AC motor; a fluctuation calculator configured to calculate a rotation speed fluctuation indicative of a fluctuation in the rotation speed; a sudden-change determinator configured to determine whether a sudden change occurs based on the rotation speed fluctuation; a switch configured to select the one-phase control current value as a current fixed value when the sudden-change determinator does not determine that the sudden change occurs, the switch configured to select the two-phase control current value as the current fixed value when the sudden-change determinator determines that the sudden change occurs, and a voltage command value calculator configured to calculate a voltage command value based on the current fixed value and a drive command value related to driving of the AC motor, the voltage command value related to a voltage applied to the inverter.