AC current regulator for asynchronous drives with PRM modulator

A pulse ratio modulated current regulator for AC motor drives is proposed. The control scheme is realized by employing a pulse ratio modulator (PRM) and a linear time-varying proportional plus derivative (PD) regulator. The proposed scheme is equivalent to a hysteresis current regulator but does not need a large bandwidth current transducer. The mathematical model and the commutation features of the PRM, in static and dynamic conditions, are presented. Simulation results of 3 kW AC drive are reported.<<ETX>>