PID–模糊控制联用法在塑料加工工艺控制方面的研究进展

主要综述了PID–模糊控制法和自整定PID–模糊控制法在塑料注塑加工过程中温度、压力等工艺参数监控中的应用。PID–模糊控制法分别利用模糊控制法和PID法对参数变化的动态过程和稳态过程进行监控,兼具了模糊控制法和PID法的优点,既具有较高的控制精度,又具有较快的响应速率。另外,在这种高精度监控方法的监控下,所制备的塑料制品的质量也较高。

Optimal fuzzy PID controller with adjustable factors based on flexible polyhedron search algorithm

A new kind of optimal fuzzy PID controller is proposed, which contains two parts. One is an on line fuzzy inference system, and the other is a conventional PID controller. In the fuzzy inference system, three adjustable factors x p, x i , and x d are introduced. Their functions are to further modify and optimize the result of the fuzzy inference so as to make the controller have the optimal control effect on a given object. The optimal values of these adjustable factors are determined based on the ITAE criterion and the Nelder and Mead′s flexible polyhedron search algorithm. This optimal fuzzy PID controller has been used to control the executive motor of the intelligent artificial leg designed by the authors. The result of computer simulation indicates that this controller is very effective and can be widely used to control different kinds of objects and processes.

Acid-pickling plates and strips speed control system by microwave heating based on self-adaptive fuzzy PID algorithm

Double self-adaptive fuzzy PID algorithm-based control strategy was proposed to construct quasi-cascade control system to control the speed of the acid-pickling process of titanium plates and strips. It is very useful in overcoming non-linear dynamic behavior, uncertain and time-varying parameters, un-modeled dynamics, and couples between the automatic turbulence control (ATC) and the automatic acid temperature control (AATC) with varying parameters during the operation process. The quasi-cascade control system of inner and outer loop self-adaptive fuzzy PID controller was built, which could effectively control the pickling speed of plates and strips. The simulated results and real application indicate that the plates and strips acid pickling speed control system has good performances of adaptively tracking the parameter variations and anti-disturbances, which ensures the match of acid pickling temperature and turbulence of flowing with acid pickling speed, improving the surface quality of plates and strips acid pickling, and energy efficiency.

Simulating a fuzzy level controller for flotation columns

Level control in flotation columns is an important factor that influences the recovery and the grade of concentrate from the column. A flotation column is a nonlinear, multi-variable problem with changeable parameters that traditional methods have difficulty controlling. We have applied fuzzy control methods to the flotation column and tested the performance of the design by Matlab/Simulink simulation. The simulations show that level control in the flotation column becomes smoother and more rapid with the fuzzy controller. Compared to PID control methods the overshoot in valve position, the adjustment time, and the robustness of the controller are all improved. This indicates that it is suitable to model fuzzy controllers in applications for the study of automatic control of flotation column.

Study on Control Performance of Bearing Temperature based on Genetic Algorithm

In order to improve the control effect of the bearing, this article studies the temperature control technology to improve the genetic algorithm, at the same time, analyze temperature simulation of bearing based on fuzzy PID control technology and improved genetic algorithm, the simulation results show that, the control method has good robustness based on Improved Genetic Algorithm. It can monitor a plurality of beating temperature, provides a new method for the detection and prevention of bearing fault.

烤箱内部温度场分布与温度控制仿真优化

为实现家用多功能烤箱工艺与温度控制方法的进一步优化,首先建立烤箱模型,进行传热机理研究;其次结合传热机理,对烤箱内部温度场分布以及烤箱温度控制系统方法进行深入探讨。结果表明:出风小孔、热风扇风机转速和背部热风扇挡板结构优化对烤箱内部温度场分布起到至关重要作用;神经网络法和模糊PID控制法是烤箱温度控制的两种行之有效的方法。研究课题对于实际家用烤箱的温度场设计及温度控制措施具有理论指导作用。