PID Controller Parameter Tuning And Optimization Technology

Improved PID (Proportional, Integral and Differential) controller and the controller is the most common industrial process control regulator. PID parameter setting of the general need of experienced engineers and technicians to complete, time-consuming and labor-intensive, combined with the actual system vary widely, there are lags, nonlinear and other factors, the PID parameter setting of a certain degree of difficulty, causing many PID controller did not tuning well, such a system naturally can not work in a satisfactory state, so a self-tuning PID controller is raised. Dynamic performance of the process of identification and PID controller tuning method of parameters can be achieved combining the self-tuning PID controller. Therefore, research on PID parameter tuning technique works with a very great practical significance.This paper describes the characteristics of PID controller algorithm, theoretical basis, the impact of parameters on the control performance, focusing on relay feedback based on self-tuning PID parameters of the basic principles of the algorithm, and made according to the Swedish scholars KJ.Astrom in the relay feedback controlled process under the observation of limit cycle oscillations and the Z-N tuning formula, a detailed derivation of the corresponding PID controller parameter tuning formula. The traditional relay-based PID feedback tuning method, you need to have large controlled processes overshoot, there is a waste of resources. This paper proposes a control process without overshoot tuning method of PID parameter. And introduced the basic principles of the soaring curve based on PID parameter auto-tuning algorithm. And with the programmable Ethernet controller (PEC8000) to be a platform, use the temperature sensors to collect temperature, host computer via Ethernet reading the temperature of PEC8000 transited, collected by setting the temperature value and temperature compared to the size of the solid state relay on-off control, temperature control to achieve the controlled object. This parameter tuning method will be charged with first-order inertial object is approximately the mathematical model plus time delay basically covers most of the controlled object, it is easy to implement in industrial control systems. The paper designs the parameter auto-tuning control system which combines the classical PID arithmetic and parameter auto-tuning arithmetic, and realize the constant temperature control of controlled object through controlling on-off of the solid state relay by the PWM impulse width modulation. The system can achieve the temperature of automatic collection and auto-tuning control according to the enactment temperature. And resolve the traditional PID control tuning parameters of the shortcomings of ineffective tuning, effectively reduced the overshoot of the controlled object and improve the controller's precision. The emphasis is laid on the principle of the parameter auto-tuning control system, software and hardware design methods. And by a large number of experiments show the feasibility of the method. The algorithm is easy to implement in industrial control systems, control is better.Summary and outlook in last part, to the full text of the research work done and the problems are summarized, and the future development of PID controller prospect.