Speed sensorless motor control apparatus and speed sensorless motor starting method

摘要

A speed sensorless motor starter 100 that starts a motor uses a double star chopper cell type modular multilevel cascade inverter 1 and an amplitude command value and a frequency command value that increases from 0 to a predetermined value over a predetermined period of time. Current command value creating means 31 for creating a command value; motor start control means 32 for starting the motor by controlling the motor drive current output from the modular multilevel cascade inverter 1 to the motor to follow the current command value; .