ADAPTIVE NONLINEAR TORQUE CONTROL OF A SWITCHED RELUCTANCE MOTOR VIA FLUX OBSERVATION

The objective of this paper is to design a high performance torque con troller for a fifth order model of a three phase switched reluctance m otor (SRM) which includes both electrical and mechanical dynamics. The same model was considered in [5] where only position control was achi eved. Industrial requirements (speed and torque control) were not nece ssarily fulfilled though. By controlling the instantaneous torque of S RM's, both speed and position control can be achieved and the fastest possible response as well as a reduction of torque ripple obtained. Th e proposed nonlinear control scheme is based on the recently developed adaptive nonlinear techniques which combine the geometric concepts of input-output linearization with the Lyapunov design of adaptive linea r control. Once the SRM model is linearized, a multivariable decouplin g linear controller for torque and unselected currents stabilization i s designed. The parameters uncertainty is compensated by the adaptive scheme. The problem of accurately measuring the SRM torque is also add ressed and a method which deduces the torque through flux observation is used. Simulation results are given to demonstrate the effectiveness of the control.