DESIGN OF DISCRETE INTEGRAL VARIABLE-STRUCTURE CONTROL-SYSTEMS AND APPLICATION TO A BRUSHLESS DC MOTOR CONTROL

A discrete integral variable structure control (DIVSC) approach is pre sented to achieve accurate servo-tracking in the presence of load dist urbance and plant parameter variations. Conditions are derived to ensu re the existence of non-ideal sliding motion. This scheme also proves that the describing motion in the non-ideal sliding region will be clo se to the ideal sliding motion. Further, procedures are proposed for d etermining the control function, the coefficients of the switching pla ne and the integral control gain. The procedures can cause the resulta nt system to have the desired properties. A microcomputer-based brushl ess DC motor servo position control system using the DIVSC approach is illustrated. Simulation results are compared with the PI controller t o demonstrate the potential of the controller. Experimental results pr esent the practical capability of the proposed controller. Copyright ( C) 1996 Elsevier Science Ltd.