Adaptive PF (PDF) Speed Control for Servo Drives

This paper proposes two model reference adaptive PF (PDF) speed control methods for servo drives. Following from the structure (PF-type) of model reference parameter adaptive control was developed to provide constant loop gain in speed control loop with changing gain (moment of inertia and/or torque factor) which makes it easier to reach nonovershooting step response as well as fast speed changing compensation caused by jump in load. The algorithm even keeps its stability at fast changing, jump-like load torque. Model reference signal adaptive control is used to provide constant loop gain in speed control loop with changing parameters exposed to a significant load. The block diagram of the adaptive control can be seen as an extended version of the PF controller, so one of the adaptation factors (which is the free parameter of the adaptive control) is given. Both model reference adaptive controls drawn up can be easily implemented because the adaptation algorithms do not need acceleration measuring (thanks to the first-order model). Simulation and experimental results demonstrate that the proposed methods are promising tools for speed control of electrical drives.