High speed adaptation system for controlled electrical drives

To develop high performances d.c. and a.c. drives the assumptions that the plant parameters are known and invariant are not valid. This paper presents a general approach for the design of adaptive control systems usable for electrical drives subject to rapid, wide and unmeasurable variations in plant parameters. This approach is based on the model reference adaptive control techniques designed using the Popov-Landau method. The feasibility and the performance of this method are illustrated by its application to the design of an adaptive speed controller for a thyristor feed d.c. drive. The adaptive controller maintains constant dynamic performances in the presence of unpredictable and unmeasurable variations of the moment of inertia, field current and in the presence of the nonlinearities occurring at low speed. The results are compared with those obtained by using the classical PI controllers.