一种基于蚁群算法的最优非线性PID控制器的设计

An Optimal Nonlinear PID Controller Based on Ant Algorithm

本文以蚁群算法为基础,提出了一种新的非线性PID控制器及其参数优化设计方法。该控制器是基于PID控制器各增益参数与误差信号之间呈现非线性关系,根据一般控制系统的阶跃响应曲线,在不同响应时间阶段PID 3个增益调节参数的理想变化情况,提出根据控制信号与误差、误差变化率之间的调节规律,拟合一组增益参数的非线性函数,并利用蚁群算法搜索出一组最优的非线性PID参数,构造最优非线性PID控制器。计算机仿真结果表明,与基于遗传算法(GA)、模拟退火算法(SA)和Z_N法设计的PID控制器(GA—PID、SA—PID)、ZN—PID)相比,这种基于蚁群算法的非线性PID控制器(NLAS—PID)具有良好的动态和稳念性能,可用于控制多种不同的对象和过程。

A new designing method for the optimal nonlinear PID controller is proposed based on ant algorithm. The relationship between the error signal and gain parameters of PID controller is nonlinear, and, a normal controlled system＇s step response figure, under the condition of ideal change of the three PID gain parameters in the different time, PID controller, basing on the tuning law between the control signal and error, differential coefficient ,fitting and constructing the nonlinear function of each gain parameter, meanwhile, by means of the ant algorithm, searching for a group of optimal nonlinear PID parameter constructing the optimal PID controller. The result of computer simulation shows that this nonlinear PID controller based on ant system algorithm （NLAS-PID） is more excellent than the GA-PID SA-PID ZN- PID controllers in the dynamic behavior of system response. This kind of PID controller possesses better dynamic controlling and robust performance, and can be used to control many different kinds of objects and process.