The PID Parameters Optimization Method Based on GA for NC Power Supply

Abstract

In the design of numerical control voltage source, the PID control parameters are usually determined by theoretical arithmetic or engineering setting method, which have some problems such as complex calculation, high demand experience, and low accuracy. This paper offers an intelligent optimization method with PID parameters k _p based on genetic algorithm. In terms of this optimization method, we design a PID parameter optimization system which consists of a microcontroller module, a host computer, and a LM2596 module. The microcontroller samples the output voltage, and receives the k _p parameters to set the LM2596 module. The host computer processes the real-time voltage value and evaluates the PID parameter based on ITAE. Meanwhile, optimal k _p parameters are generated by the genetic algorithm. The experimental results show that the mean value of ITAE reduces in the process of genetic algorithm, reflecting the fact that PID control effect is improved obviously and the parameters are becoming optimal. According to the test of full range k _p and ITAE table, we can conclude that k _p set by the genetic algorithm is superior to k _p set by Ziegler–Nichols (Z–N) method which is the optimal solution in the full scale. This paper is of instructive value in the field of setting parameters of PID control system.