Tuneing Of PID Contrller Parameters On Immune Genetic Algorithm And Its Application In Control System Based On Industrial Ethernet

The parameter tuning technology of PID controller is always the important point in the field of the autocontrol. Because of the nonlinearity and time-varying uncertainties of controlled objects in the application of industry production, the accurate mathematical model can not be built, and the common PID controller can't achieve the ideal control effects. To adapt to the complex industry status and high control demands, people continuously search for the parameter tuning technology of PID controller. The traditional methods can not fit the request of PID parameter robust tuning, so the PID parameters optimization has become the key of resolving the problem. Because of the rapid development of computer technology, many researchers begin to study some optimal algorithms to optimize the parameters, such as adaptive intelligent controller, the neural net controller, the genetic algorithm controller and so on. As a intelligent method which combines with life sciences theory, genetic algorithm can highly parallel and globally search. It has formed a set of moderately complete algorithm system theory and can be combined with other algorithms as a concept. Immune genetic algorithm is a good example of that, which combine genetic algorithm with immune algorithm's characteristic and overcomes the defeats of immune algorithm. It is able to avoid precocious phenomena well and raise the optimal speed effectively.This paper introduces PID controller and the parameter tuning technology of it. The PID controller parameter has been tuned by combining the intelligent algorithms which are commonly used in these years, such as genetic algorithm, BP neural network and immune genetic algorithm which based on immune theory. And then simulate the tuning results using MATLAB. The results show that the PID controller can achieve the good control effect after optimizing parameters by using intelligent algorithms. According to the actual need, we design experimental system's software and hardware platform of networked control technology based on Ethernet technology. This paper describes the overall design of hardware, the hardware selection of site model device and the hardware installation of network control system, and introduces virtual instrument technology and LABVIEW language. Then design the software configuration and upper computer programming separately. The signal acquisition and setting subroutines, liquid level control subprogram of upper case and the design of upper computer monitor interface have been completed. At last, we tune the system's PID controller parameter using immune genetic algorithm and analyzes the results.