Control circuit for brushless DC motor e.g. for robot drive

摘要

A control circuit for a brushless electric motor has a unit to calculate a torque guide variable, a unit to calculate the torque current flowing in the motor armature winding, which is in phase with the motor's electrical angle, a unit to calculate a phase displacement current which lags or leads the torque current by 90 degrees and a unit to calculate a setpoint current from these two preceding currents. The unit to calculate the phase displacement current has a unit to calculate an upper limit for the current based on the speed guide variable, a unit to calculate the actual armature current and a device to see if this current is following the setpoint current.