EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, vol.11, no.1, pp.39-48, 2001 (SCI-Expanded)
The most common problem of the slip recovery system is stabilizing the system under power system disturbances, such as the change of supply voltage. Two back-to-back proportional-plus-integral (PI) controllers are used in a closed-loop control system, to control the DC-link current and speed. In order to estimate parameters of the controllers using root-locus technique, a non-linear transient model of the drive is linearized around the steady-state operating point. The performance of the drive in the presence of disturbance signals is studied and finally the eliminating speed error signal and the continuous variations of the inverter-firing angle are illustrated.