基于改进GA的注射机料筒温度二自由度PID控制

Two-Degree-of-Freedom PID Control of Barrel Temperature of Injection Molding Machine Based on Improved GA

由于注射机料筒温度控制系统具有时变性、非线性及滞后性等特点,造成料筒温度在实际生产过程中难以实现精准控制。对此,提出一种把遗传算法和粒子群算法结合的改进遗传算法以及并行式二自由度PID,用该并行式二自由度PID替换料筒温度控制系统中的常规PID,并用改进遗传算法对并行式二自由度PID参数优化。通过仿真验证可知,研究所采用的方法具有良好的控制效果,其系统响应快、调节时间小、超调量小、鲁棒性好且抑制扰动能力强。因此,该方法能获得更好的性能指标值,更好地满足注射机料筒温度控制的精准要求。

Due to the characteristics of time-varying,non-linear and hysteresis of the barrel temperature control system of injection molding machine,it is difficult to achieve accurate control of barrel temperature in the actual production.In this regard,an improved genetic algorithm combining a genetic algorithm and a particle swarm algorithm and a parallel twodegree-of-freedom PID are proposed.The parallel two-degree-of-freedom PID is used to replace the conventional PID in the barrel temperature control system,and the improved genetic algorithm is used to optimization of parallel two-degreeof-freedom PID parameters.The simulation results show that the method used in this research has good control effect,its system response is fast,the adjustment time is small,the amount of overshoot is small,the robustness is good,and the ability to suppress disturbances is strong.Therefore,this method can obtain better performance index values and better meet the precise requirements of barrel temperature control of injection molding machines.