Drive system controlling method for asynchronous drive motor of dump truck, involves driving electric motor with rotary field frequency in warming phase after stopping of motor with specific percentage slippage

摘要

The method involves driving an electric motor (2) with a rotary field frequency (n1) of approximately 200 hertz in a warming phase after stopping of the motor with 100 percentage slippage. The electric motor is provided downstream to a pulse power converter (4). A direction of rotation of a magnetic rotary field (F) produced in the electric motor is changed in a periodic alternating manner, with an alternating frequency (f). An effective value (Ueff) of phase voltages (UL1, UL2, UL3) is driven to a value zero for a short-time, during each change of the rotary field direction. An independent claim is also included for a drive system with a pulse power converter.