模拟复合正交神经网络控制器在直流调速系统中的应用

在数字复合正交神经网络的基础上提出一种模拟复合正交神经网络,并用于直流双闭环调速系统中。控制器采用模拟复合正交神经网络的直接自适应控制方法,并对带有负载干扰的直流双闭环调速系统作了PI控制与神经网络控制的仿真实验。仿真结果表明,相对于常规PI控制器,该神经网络控制器具有自学习,自适应功能,速度跟踪获得了满意的控制效果。该模拟神经控制器能用于直流与交流调速系统中。     

永磁伺服系统三闭环调节器的设计

交流伺服控制系统要求以动态稳定和稳态精度为主,故电流环和转速环常采用PI调节器。转速调节器是调速系统的主导调节器,对负载变化起抗扰作用,同时又希望速度响应足够快。针对这一问题,介绍了PI、IP、PDFF三种不同形式转速调节器的设计方法,并比较分析了不同调节器的优缺点。位置环是高阶动态调节系统,其目标是快速跟踪给定,通过合理的假设简化,给出了位置环控制器的设计方法。最后,仿真对比验证了不同控制器的控制效果。     

异步电动机矢量控制系统Fuzzy-PI控制器的设计

针对异步电动机动态数学模型的非线性特性,提出并设计了三个Fuzzy-PI复合控制器,分别对直接矢量控制系统中的速度、转矩和磁链进行控制.最后利用Matlab软件对系统进行了仿真研究.仿真结果表明:Fuzzy-PI复合控制器具有良好的控制效果,优于一般模糊控制器和PI控制器,能够改善系统的动态和静态性能.     

无刷直流电动机调速系统数字控制器设计与开发

选用MSP430F149单片机作为控制器核心,设计了一种无刷直流电动机双闭环调速系统数字控制器,采用转速电流双闭环PI控制策略,使无刷直流电动机调速系统具有优良的动、静态性能。     

基于模糊自适应PI控制的电梯调速系统仿真研究

根据模糊自适应PID控制理论,对电梯变频调速矢量控制系统中的转速PI调节器进行优化设计,并应用电机矢量控制系统的仿真模型进行仿真分析。仿真结果表明,采用模糊自适应PI控制器的变频调速系统具有响应时间快、超调量小等优点。     

精确模型匹配方法在可控硅直流调速系统上的应用

本文在讨论用PI调节器实现可控硅直流调速系统的基础上,探讨了用精确模型匹配方法来完成可控硅直流调速系统的设计方案,并给出了实验曲线;对通常PI速度调节器不能达到的快速响应的电力传动装置,用模型匹配控制系统可以达到,并可以一次性设计较好的控制器,且非常易于过渡到自适应控制。     

基于滑模自抗扰控制的开关磁阻电机调速系统

开关磁阻电机的双凸极结构和开关电源供电方式使其电磁场存在非线性饱和特性，致使其运行时转矩脉动大，传统控制方法很难完成平稳调速。针对该问题，提出开关磁阻电机调速系统的滑模自抗扰控制策略。首先，内环根据开关磁阻电机数学模型设计自抗扰电流控制器，提高电流的响应速度和鲁棒性；其次，外环设计滑模速度控制器取代传统的PI控制器，并证明了系统的稳定性，增强了速度的鲁棒性；最后利用仿真与实验验证该控制策略的有效性。与传统的开关磁阻电机调速系统控制策略对比，能有效改善启动电流过大、转速超调和转矩脉动问题，提高了系统的响应速度和鲁棒性。     

永磁同步电机的指数型分数阶PI速度控制

针对永磁同步电机速度环控制,设计一种指数型分数阶比例积分(FO[PI])控制器。FO[PI]控制器比PI控制器多一个可调参数,且在一定范围内对本身和被控对象参数摄动不敏感,因此能够更灵活的控制被控对象,获得比PI控制器更理想的控制性能。在输入为阶跃信号时,对采用FO[PI]控制器的系统与采用PI控制器的系统进行仿真实验对比,仿真结果表明:FO[PI]控制器在速度跟踪性能以及参数摄动鲁棒性方面均要优于PI控制器。     

某电控液驱车辆比例阀控马达系统特性研究

以电控液驱车辆的液压马达回转系统为背景,对电液比例阀控马达系统进行控制性能研究。首先分析了其系统组成及工作原理,分别采用变结构抗饱和PI控制和模糊PID控制2种控制方法对电液比例阀控马达系统的控制器进行了设计,利用MATLAB/Simulink软件分别建立了采用不同控制器的电液比例阀控马达系统的仿真模型。仿真结果表明:与变结构抗饱和PI控制相比较,模糊PID控制在响应速度和平稳性等方面具有显著优势。     

二自由度PID在PMSM电流环中的应用

针对电流环频域数学模型,设计了一种二自由度控制器并给出了参数整定方法。基于期望的系统阻尼比和阶跃响应的上升时间,结合极点配置理论计算得到二自由度控制器参数。仿真和实验结果表明,相较于传统PI控制,采用二自由度控制的永磁同步电机(PMSM)调速系统有效地解决了常规PI控制难以兼顾电流环的跟踪性能与抗扰性能的缺陷。     

变结构PI控制器的设计及其在光电跟踪系统中的应用

为了给光电跟踪系统提供高性能的伺服控制,基于传统的PI控制器原理,结合变结构的思想,设计了一种变结构PI控制器(VSPI)。介绍了该控制器的工作原理并讨论了设计参数的选择。基于某型号光电跟踪系统,分别对采用了VSPI、抗积分饱和PI控制器(AWPI)和积分分离PI控制器(ISPI)作为位置回路控制器的伺服控制系统进行了仿真和实验。实验结果表明,采用了VSPI的光电跟踪系统基本无超调,上升时间为0.378s,稳定时间为0.488s,跟踪精度为1.26″。该系统结构简单,能实现嵌入式实时控制;与其他两种控制器相比综合性能更好,完全满足光电跟踪系统精度高、响应快的要求。     

一类时滞系统的PID稳定控制器设计

针对工业控制过程中常见的时滞系统,给出了快速计算PI和PID控制器所有稳定参数集的方法。推导了系统开环不稳定情形下稳定控制器存在的必要性条件．通过在该稳定参数区域上进行性能指标寻优,可以得到满足控制器设计性能指标要求的PID控制器参数区域。仿真实例表明了该方法的优越性。     

A hybrid disturbance rejection control solution for variable valve timing system of gasoline engines

A novel solution for electro-hydraulic variable valve timing (VVT) system of gasoline engines is proposed, based on the concept of active disturbance rejection control (ADRC). Disturbances, such as oil pressure and engine speed variations, are all estimated and mitigated in real-time. A feed-forward controller was added to enhance the performance of the system based on a simple and static first principle model, forming a hybrid disturbance rejection control (HDRC) strategy. HDRC was validated by experimentation and compared with an existing manually tuned proportional-integral (PI) controller. The results show that HDRC provided a faster response and better tolerance of engine speed and oil pressure variations.     

Antlion optimizer-ANFIS load frequency control for multi-interconnected plants comprising photovoltaic and wind turbine

This paper proposes optimal load frequency control (LFC) designed by Adaptive Neuro Fuzzy Inference System (ANFIS) trained via antlion optimizer (ALO) for multi-interconnected system comprising renewable energy sources (RESs). Two systems are modeled and investigated; the first one has two plants of grid connected photovoltaic (PV) system with maximum power point tracker (MPPT) and thermal plant while the second comprises four plants of thermal, wind turbine and grid connected PV systems. ALO is employed to get the optimal gains of Proportional–Integral (PI) controller such that the integral time absolute error (ITAE) of frequency and tie line power deviations is minimized. The input and output of the optimized PI controller are used to train the ANFIS-LFC with Gaussian surface membership functions. Different load disturbances are studied and the results are compared with other reported approaches. The obtained results confirmed the accuracy and reliability of the proposed approach in designing LFC for multi-interconnected power systems.     

H∞ output-feedback fuzzy proportional-integral control of fully delayed input/output systems

This paper presents the output-feedback fuzzy proportional-integral (PI) controller design for uncertain nonlinear systems with both fully delayed input and output. Based on the Takagi–Sugeno (T–S) fuzzy model representation, the output-feedback PI control is realized via parallel distributed PI compensation and novel LMI gain design. Although the T–S fuzzy PI controller is simple, asymptotic output regulation is assured to overcome the effect of uncertainty, state delay, and full input/output delays. When considering disturbance and measurement noise, the control performance is achieved by robust gain design. Furthermore, state observers and bilinear matrix inequality conditions are removed in this paper. Finally, time-delay Chua׳s circuit system and a continuous-time stirred tank reactor are taken as applications to show the expected performance.     

Design of controller using variable transformations for a nonlinear process with dead time

In this work, a globally linearized controller (GLC) for a first-order nonlinear system with dead time is proposed. This is similar to the GLC proposed by Ogunnalke [Ind. Eng. Chem. Process. Des. Dev. 25, 241-248 (1986)] for nonlinear systems without dead time. Two methods are proposed. One is based on the Smith prediction from the model in the transformed domain and the other is based on Newton's extrapolation method. The simulation study is made on the conical tank level process and the results are compared with those obtained using a conventional PI controller and the Smith PI controller based on the transfer function model about the operating point 39%. Finally, experimental results on the laboratory conical tank level process are also given.     

Adaptive PI controller to voltage regulation in power systems: STATCOM as a case study

Static synchronous compensator (STATCOM) provides the means to improve quality and reliability of a power system as it has the functional capability to handle dynamic disturbances, such as transient stability and power oscillation damping as well as to providing voltage regulation. In this paper, a robust adaptive PI-based optimal fuzzy control strategy is proposed to control a STATCOM used in distribution systems. The proposed intelligent strategy is based on a combination of a new General Type-II Fuzzy Logic (GT2FL) with a simple heuristic algorithm named Teaching Learning Based Optimization (TLBO) Algorithm. The proposed framework optimally tunes parameters of a Proportional-Integral (PI) controller which, similar to most of other researchers regarding control of STATCOM, are in charge of controlling the device. The proposed controller guaranties robustness and stability against uncertainties caused by external disturbances or ever-changing nature of the power systems. The TLBO optimizes the parameters of the controller as well as the input and output membership functions. To validate the efficiency of the proposed controller, the obtained simulation results are compared with those of the two most recent researches applied in this field, namely, conventional Proportional Integral (PI) controller and Optimal Fuzzy PI (OFPI) controller. Results demonstrate the successfulness and effectiveness of the proposed online-TLBO General Type-2 Fuzzy PI (OGT2FPI) controller and its superiority over conventional approaches.     

Model predictive control for a class of systems with isolated nonlinearity

The paper is concerned with an overall convergent nonlinear model predictive control design for a kind of nonlinear mechatronic drive systems. The proposed nonlinear model predictive control results in the improvement of regulatory capacity for reference tracking and load disturbance rejection. The design of the nonlinear model predictive controller consists of two steps: the first step is to design a linear model predictive controller based on the linear part of the system at each sample instant, then an overall convergent nonlinear part is added to the linear model predictive controller to combine a nonlinear controller using error driven. The structure of the proposed controller is similar to that of classical PI optimal regulator but it also bears a set-point feed forward control loop, thus tracking ability and disturbance rejection are improved. The proposed method is compared with the results from recent literature, where control performance under both model match and mismatch cases are enlightened.     

Design and experimental realization of a robust decentralized PI controller for a coupled tank system

This paper presents design and realization of a robust decentralized PI controller for regulating the level of a coupled tank system. The proposed controller is designed based on a predefined reference transfer function model in which we adopt a frequency matching of actual and reference models. Realization of control algorithms for a multivariable system is often complicated owing to uncertainties in the process dynamics. In this paper, initially a frequency response fitting model reduction technique is adopted to obtain a First Order Plus Dead Time (FOPDT) model of each higher order decoupled subsystem. Further, using the obtained reduced order model, the proposed robust decentralized PI controller is designed. The stability and performance of the proposed controller are verified by considering multiplicative input and output uncertainties. The performance of the proposed robust decentralized controller has been compared with that of a decentralized PI controller. To validate the performance of the proposed control approach, real-time experimentation is pursed on a Feedback Instrument manufactured coupled tank system.     

Buck 变换器导通模式转换滑模 PI 混合控制策略

为了满足Buck变换器由待机或轻载向较大负载状态快速转换的需求,基于对传统平均电流控制Buck变换器的动态性能分析,提出了一种改进的适用于断续导通模式/连续导通模式过程的滑模PI混合控制策略。该策略电压外环依据系统状态和导通模式分别采用PI控制器和滑模控制器,其中稳态工况应用PI控制器,负载增大动态工况根据导通模式转换为滑模控制器,并通过统一校正的平均电感电流实现导通模式的准确判断。该混合控制策略可以有效结合PI控制与滑模控制各自的稳态与动态性能优势。仿真和实验结果表明,相比于传统平均电流控制,本策略动态响应时间缩短约65%,电压跌落减小35%以上。