The coagulation process is one of the most important stages in water treatment plant, which involves many complex physical and chemical phenomena. Moreover, coagulant dosing rate is non-linearly correlated to raw wate...The coagulation process is one of the most important stages in water treatment plant, which involves many complex physical and chemical phenomena. Moreover, coagulant dosing rate is non-linearly correlated to raw water characteristics such as turbidity, conductivity, PH, temperature, etc. As such, coagulation reaction is hard or even impossible to control satisfactorily by conventional methods. Based on neural network and rule models, an expert system for determining the optimum chemical dosage rate is developed and used in a water treatment work, and the results of actual runs show that in the condition of satisfying the demand of drinking water quality, the usage of coagulant is lowered.展开更多
In view of the problem that the fixed-parameter controller can not fulfil the requirements of control-ling systems that have a usually changing characterstic. this article gives the control algorithm and simulationpro...In view of the problem that the fixed-parameter controller can not fulfil the requirements of control-ling systems that have a usually changing characterstic. this article gives the control algorithm and simulationprogram of an expert self-adaptive PID (proportional integral differential) controller. The algorithm is based ona series of methods such as critical proportion band method, response curved line method, pattern recognition ap-proach and separable integral control algorithm. Formulas and the concrete tuning rule of the pattern recognitionapproach are give. The result shows that under changing loop parameters the controlling effect of this controlleris evidently much better than that of a fixed parameter controller展开更多
To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been propose...To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering.展开更多
This paper presents the design and performance analysis of Differential Evolution(DE)algorithm based Proportional-Integral-Derivative(PID)controller for temperature control of Continuous Stirred Tank Reactor(CSTR)plan...This paper presents the design and performance analysis of Differential Evolution(DE)algorithm based Proportional-Integral-Derivative(PID)controller for temperature control of Continuous Stirred Tank Reactor(CSTR)plant in che-mical industries.The proposed work deals about the design of Differential Evolu-tion(DE)algorithm in order to improve the performance of CSTR.In this,the process is controlled by controlling the temperature of the liquid through manip-ulation of the coolantflow rate with the help of modified Model Reference Adap-tive Controller(MRAC).The transient response of temperature process is improved by using PID Controller,Differential Evolution Algorithm based PID and fuzzy based DE controller.Finally,the temperature response is compared with experimental results of CSTR.展开更多
The most important parameters which control the electrolytic process are the concentrations of zinc and sulfuric acid in the electrolyte. An expert control strategy for determining and tracking the optimal concentrati...The most important parameters which control the electrolytic process are the concentrations of zinc and sulfuric acid in the electrolyte. An expert control strategy for determining and tracking the optimal concentrations was proposed, which uses neural networks, rule models and a single loop control scheme. First, the process was described and the strategy that features an expert controller and three single loop controllers was explained. Next, neural networks and rule models were constructed based on statistical data and empirical knowledge on the process. Then, the expert controller for determining the optimal concentrations was designed through a combination of the neural networks and rule models. The three single loop controllers used the PI algorithm to track the optimal concentrations. Finally, the implementation of the proposed strategy were presented. The run results show that the strategy provides not only high purity metallic zinc, but also significant economic benefits.展开更多
针对存在临界点的A类被控对象及不存在临界点的B类被控对象,分别采用其-180?和-120?相位点的频率和增益提出了PID (Proportional-integral-derivative)控制器参数的优化整定方法.基于Tchebyshev多项式和分数阶积分器求取被控对象-180?或...针对存在临界点的A类被控对象及不存在临界点的B类被控对象,分别采用其-180?和-120?相位点的频率和增益提出了PID (Proportional-integral-derivative)控制器参数的优化整定方法.基于Tchebyshev多项式和分数阶积分器求取被控对象-180?或-120?相位点的频率和增益,建立其积分滞后模型.采用负载扰动下跟踪误差平方和(Sum of squares of tracking errors, SSE)最小作为优化指标,使闭环系统具有强的鲁棒性的最大灵敏度和最大补灵敏度为约束方程,针对两类被控对象,分别建立了基于-180?和-120?相位点频率和增益的PID控制器比例、积分与微分三个参数的优化整定规则.通过与其他常用PID控制方法的仿真与物理对比实验,表明所提方法的优越性.展开更多
超声电机具有明显的非线性和时变特性。为提高其控制性能,神经网络等复杂控制策略已被提出,但这些方法计算复杂,导致系统硬件成本提高,不利于超声电机的产业化应用。为得到计算量较小且具有较高控制性能的控制策略,通过对超声电机典型...超声电机具有明显的非线性和时变特性。为提高其控制性能,神经网络等复杂控制策略已被提出,但这些方法计算复杂,导致系统硬件成本提高,不利于超声电机的产业化应用。为得到计算量较小且具有较高控制性能的控制策略,通过对超声电机典型控制过程的理论分析与转速控制实验研究,提出一种仅有2条专家规则的简单专家比例–积分–微分(proportional integral derivative,PID)控制方法。专家规则根据当前控制状况,调节PID控制参数,改善控制性能。与常规PID控制相比,所提方法的在线计算量增加不大,易于采用单片机等器件实现。多种变化工况下的实验表明,所提方法对超声电机特性变化及负载扰动的适应能力强,控制效果较好,为超声电机的规模化应用提供了一种可选的控制方法。展开更多
基金This work was supported by the project 863 ofChina(No.863-511092)
文摘The coagulation process is one of the most important stages in water treatment plant, which involves many complex physical and chemical phenomena. Moreover, coagulant dosing rate is non-linearly correlated to raw water characteristics such as turbidity, conductivity, PH, temperature, etc. As such, coagulation reaction is hard or even impossible to control satisfactorily by conventional methods. Based on neural network and rule models, an expert system for determining the optimum chemical dosage rate is developed and used in a water treatment work, and the results of actual runs show that in the condition of satisfying the demand of drinking water quality, the usage of coagulant is lowered.
文摘In view of the problem that the fixed-parameter controller can not fulfil the requirements of control-ling systems that have a usually changing characterstic. this article gives the control algorithm and simulationprogram of an expert self-adaptive PID (proportional integral differential) controller. The algorithm is based ona series of methods such as critical proportion band method, response curved line method, pattern recognition ap-proach and separable integral control algorithm. Formulas and the concrete tuning rule of the pattern recognitionapproach are give. The result shows that under changing loop parameters the controlling effect of this controlleris evidently much better than that of a fixed parameter controller
文摘To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering.
文摘This paper presents the design and performance analysis of Differential Evolution(DE)algorithm based Proportional-Integral-Derivative(PID)controller for temperature control of Continuous Stirred Tank Reactor(CSTR)plant in che-mical industries.The proposed work deals about the design of Differential Evolu-tion(DE)algorithm in order to improve the performance of CSTR.In this,the process is controlled by controlling the temperature of the liquid through manip-ulation of the coolantflow rate with the help of modified Model Reference Adap-tive Controller(MRAC).The transient response of temperature process is improved by using PID Controller,Differential Evolution Algorithm based PID and fuzzy based DE controller.Finally,the temperature response is compared with experimental results of CSTR.
文摘The most important parameters which control the electrolytic process are the concentrations of zinc and sulfuric acid in the electrolyte. An expert control strategy for determining and tracking the optimal concentrations was proposed, which uses neural networks, rule models and a single loop control scheme. First, the process was described and the strategy that features an expert controller and three single loop controllers was explained. Next, neural networks and rule models were constructed based on statistical data and empirical knowledge on the process. Then, the expert controller for determining the optimal concentrations was designed through a combination of the neural networks and rule models. The three single loop controllers used the PI algorithm to track the optimal concentrations. Finally, the implementation of the proposed strategy were presented. The run results show that the strategy provides not only high purity metallic zinc, but also significant economic benefits.
文摘针对存在临界点的A类被控对象及不存在临界点的B类被控对象,分别采用其-180?和-120?相位点的频率和增益提出了PID (Proportional-integral-derivative)控制器参数的优化整定方法.基于Tchebyshev多项式和分数阶积分器求取被控对象-180?或-120?相位点的频率和增益,建立其积分滞后模型.采用负载扰动下跟踪误差平方和(Sum of squares of tracking errors, SSE)最小作为优化指标,使闭环系统具有强的鲁棒性的最大灵敏度和最大补灵敏度为约束方程,针对两类被控对象,分别建立了基于-180?和-120?相位点频率和增益的PID控制器比例、积分与微分三个参数的优化整定规则.通过与其他常用PID控制方法的仿真与物理对比实验,表明所提方法的优越性.
文摘超声电机具有明显的非线性和时变特性。为提高其控制性能,神经网络等复杂控制策略已被提出,但这些方法计算复杂,导致系统硬件成本提高,不利于超声电机的产业化应用。为得到计算量较小且具有较高控制性能的控制策略,通过对超声电机典型控制过程的理论分析与转速控制实验研究,提出一种仅有2条专家规则的简单专家比例–积分–微分(proportional integral derivative,PID)控制方法。专家规则根据当前控制状况,调节PID控制参数,改善控制性能。与常规PID控制相比,所提方法的在线计算量增加不大,易于采用单片机等器件实现。多种变化工况下的实验表明,所提方法对超声电机特性变化及负载扰动的适应能力强,控制效果较好,为超声电机的规模化应用提供了一种可选的控制方法。