Cascade sliding mode variable structure control of permanent magnet synchronous linear servo system

In allusion to high precision linear servo system the static thrust pulsation caused by the two hysteresis regulator in traditional direct thrust control, this essay designs cascade sliding mode variable structure control. In this system, the inner ring adopts sliding mode variable structure direct thrust control which can largely reduce the thrust pulsation and keep the merits of the traditional direct thrust control; the outer ring adopts sliding mode variable structure speed control which has high-robustness against system parameter perturbation, all kinds of noise disturbance. According to Simulation research, the new control scheme following can largely reduce the thrust pulsation and improve dynamic and static performance. Compare with traditional method, linear servo system designed with this control mode has high robustness, better interference rejection and track ability.