Active damping control of PWM CSI high power induction motor drives

In this paper an active damping control scheme is proposed for use in high power current source inverter fed induction motor drives. The proposed scheme can effectively solve the stability problem associated with the drive using Vlf (Volts per Hertz) control. By integrating the active damping control into the V/f control, the stability of the drive is substantially improved and the LC resonance caused by inverter capacitor and motor inductance is effectively suppressed. In addition, the drive system using this scheme becomes less parameter sensitive and easy to implement. The performance of the proposed drive is investigated through eigenvalue analysis. A 5hp prototype drive is constructed and the theoretical analysis is verified by experiments. The feasibility of using this control scheme in high power drives is also investigated.