McDermott Will & Emery LLP
Apparatus and method for controlling AC motor and module therefor
A method and apparatus for controlling a permanent magnet synchronous motor by accurately detecting 3-phase motor currents from a DC input current in a full voltage range are provided. In the motor control apparatus for detecting the 3-phase motor currents on the basis of the value of the current detected at a DC side of a PWM inverter, when a difference width between PWM pulse signals of two of three phases of the 3-phase PWM inverter which cannot detect the motor currents is not larger than a predetermined value or when the output voltage of the 3-phase PWM inverter is low, the apparatus automatically reduce the carrier frequency of the PWM inverter.
Hitachi, Ltd.
H H H H
H02P H02M H02P H02M
inventional additional inventional additional
Tsunehiro Hidefumi Kazuaki Yoshiki
Endo Shirahama Tobari Itou