High-performance double-rate cascade PID control method, device and system

Abstract

The invention discloses a high-performance double-rate cascade PID control method, device and system, and belongs to the technical field of industrial production process control. The method comprises the steps of firstly designing an inner loop PID controller, obtaining a dynamic model of an inner loop closed-loop control system, then employing the condition that the set value of the inner loop PID controller is not changed in the sampling period of an outer loop, an outer loop dynamic model based on dynamic characteristics of the inner loop PID closed-loop control system is established by adopting a lifting technology, then an outer loop PID controller is designed based on the outer loop dynamic model, and high-performance double-rate cascade PID control is carried out by adopting the determined inner loop PID controller and the outer loop PID controller. According to the invention, the problems that frequent unknown interference or unknown change of dynamic characteristics causes dynamic change, mutual influence and even resonance of the inner loop and the outer loop of the cascade industrial process, and the control target of the cascade industrial process cannot be realized by adopting the conventional cascade PID control technology are solved.

Description

technical field [0001] The invention relates to the technical field of industrial production process control, in particular to a high-performance dual-rate cascade PID control method, device and system. Background technique [0002] The cascade industrial process has been widely used in actual industrial generation. The cascade industrial process consists of two inner and outer rings with different time scales. The inner ring is a fast process, the outer ring is a slow process, and the output of the inner ring is the output of the outer ring. enter. Most of the cascade industrial process control adopts conventional cascade PID control, and the conventional cascade PID controller design method uses the inner and outer loops to design PID controllers separately, first design the inner loop PID controller, and then design the outer loop PID controller, the outer loop PID controller The output of the controller is used as the setpoint of the inner loop controller. In general c...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the problem that frequent unknown disturbances or unknown changes in dynamic characteristics cause dynamic changes in the inner loop and outer loop of the cascade industrial process, interact with each other, and even cause resonance, it is impossible to use conventional cascade PID control technology to achieve the control goal of the cascade industrial process. The present invention proposes a high-performance dual-rate cascade PID control method, device and system to eliminate the interaction of dynamic changes in the inner loop and outer loop of the cascade industrial process caused by frequent unknown interference or unknown changes in dynamic characteristics, and improve cascade The dynamic performance of the control system of the industrial process, realizing the high-performance dual-rate cascade PID control

Images