Method and apparatus for stability control of open loop motor drive operation

摘要

Motor drives (10) and control methods (100) are presented for sensorless motor speed control in which inverter output currents (i a , i b , i c ) are sampled from the inverter output, and a frequency modulation value (25a) is determined based on the current feedback and either one or more voltage commands ( v * a , v * b , v * c ) or one or more voltage feedback signals ( V a , V b , V c ). A speed or frequency setpoint (21, 31) is adjusted at least partially according to the frequency modulation value (25a) to provide an adjusted frequency or speed setpoint value (31 a) that is then used in controlling (110) the inverter (14) to provide stability control to mitigate hunting or motor stoppage.