The Research of a Piezoelectric Valve Positioner Control Algorithm

The dynamic characteristic of smart valve positioner is nonlinear in its operational range, while the traditional five-step method or a single switch PID control algorithm could not meet a nonlinear model uncertain control system for high-speed, high-precision control. This paper presents a new control algorithm which five-step switching method with backward PWM and PID control method combines, it realize that the opening degree of the valve is fast and accurate positioning under conditions in nonlinear. The experimental result show that the control algorithm is better than the five-step control method and PID control algorithm, and the algorithm is simple, high reliability, speed control, and have certain adaptive and robustness, valve positioning accuracy to meet the control requirerments.