基于模糊自整定PID的二质量伺服控制系统的研究

在分析了直流伺服系统电学方程和动力学方程的基础上,建立了二质量伺服系统的数学模型及SIMULINK仿真模型.通过MATLAB模糊工具箱和SIMULINK,实现了模糊自整定PID控制器的设计和系统仿真.仿真结果表明用模糊自整定PID控制二质量伺服系统,系统响应快,超调量小,稳定精度高.     

模糊参数自整定PID控制器的设计与仿真研究

为实现PID参数的自动整定,在PID控制和模糊控制的基础上,设计了一种用于某型热像仪分子筛激活机中恒温炉温控系统的模糊参数自整定PID控制器,它基于PID参数的优化规律利用模糊控制规则对PID参数进行在线的自动整定.与常规PID温控系统比较,该控制器的系统超调量明显减小,控制系统的动静态性能均得到改善,升温速度和目标温度控制精度超过了设计指标,且结构简单、计算量小.系统仿真验证了该设计的有效性与实用价值.     

基于PROFIBUS-DP的模糊自整定PID控制器的设计

介绍了用SPC3设计PROFIBUS-DP从站．并与模糊自整定PID算法相结合、实现智能控制。还介绍了PROFIBUS-DP从站的状态机。     

参数自调整模糊控制在空调系统中的应用

对于典型的非线性、时变、滞后的空调系统,基于精确模型的经典控制和现代控制方法难以取得良好的控制品质。而模糊控制则因其具有无需建立被控对象数学模型,鲁棒性与抗干扰性强等特点,能很好地适应空调系统的控制要求而得到广泛的应用。在分析了基本的PID参数整定对系统性能影响的基础上。将模糊控制技术与经典PID控制相结合。建立参数自调整模糊控制器．并用MATLAB软件对该控制器进行仿真。结果表明,参数自调整模糊控制器具有较快的响应速度和较小的稳态误差,同时对被控对象的参数变化有一定的自适应能力。     

参数模糊自整定PID控制器在恒压供水系统中的应用

本文提出了一种基于模糊控制理论的恒压供水系统,针对传统PID控制器的特点,将模糊控制技术引入到PID参数自整定过程中,根据不同情况在线自整定PID参数,并采用变频调速技术,节能效果明显,有一定的理论与实际应用价值.     

模糊自适应PID控制器在SRD调速系统中的应用

在设定开关磁阻电机(SRM)最优的θon和θoff前提下,设计一个模糊自适应PID控制器,使SRD调速系统获得最佳性能。     

控制力矩陀螺框架系统的谐振抑制与精度控制

控制力矩陀螺(CMG)框架系统的速率控制精度是影响其输出力矩精度的重要因素,系统中谐波减速器提高了框架系统的动态响应能力,但其产生的机械谐振大幅降低了系统的控制精度.为抑制框架系统的谐振并满足系统的控制精度,本文建立了框架系统的动力学模型,根据系统动态性能要求选取合适的阻尼系数来设计系统主导极点,使控制器产生的零点与机械谐振对应的极点重合形成偶极子,从而抑制系统的机械谐振.仿真和实验结果显示:提出的方法有效地抑制了控制力矩陀螺框架系统的谐振,0.175 rad/s恒速控制精度为0.002,0.175 sin(2πt) rad/s正弦随动控制的幅值相对误差为3.28％,相位差为0.13 rad.结果很好地满足了控制力矩陀螺的高精度输出力矩需求.     

Calculation of PID controller parameters by using a fuzzy neural network

In this paper, we use the fuzzy neural network (FNN) to develop a formula for designing the proportional-integral-derivative (PID) controller. This PID controller satisfies the criteria of minimum integrated absolute error (IAE) and maximum of sensitivity (Ms). The FNN system is used to identify the relationship between plant model and controller parameters based on IAE and Ms. To derive the tuning rule, the dominant pole assignment method is applied to simplify our optimization processes. Therefore, the FNN system is used to automatically tune the PID controller for different system parameters so that neither theoretical methods nor numerical methods need be used. Moreover, the FNN-based formula can modify the controller to meet our specification when the system model changes. A simulation result for applying to the motor position control problem is given to demonstrate the effectiveness of our approach.     

一类切换模糊PID控制器设计及其仿真

提出了一类高动态性能切换模糊PID控制器设计方法.通过对传统PID控制中比例控制和微分控制作用的分析,结合模糊PID控制器鲁棒性能和自适应性好的优点,设计了一类新的模糊控制器.由于该类控制器先后经历比例控制,微分控制和模糊PID控制的切换,使被控系统不仅具有一般模糊PID控制器的所具有的良好的鲁棒性能和自适应性,而且与一般模糊控制器相比具有更小的超调量和调节时间,是一类动态性能良好的控制器.最后将该控制器应用于一伺服系统进行仿真对比,并给出了Simulink仿真框图.仿真结果说明了该控制器的优越性.     

基于模糊PID控制器的多电机控制系统

传统的PID控制在对象发生变化时,控制器的参数难以自动调整.该文将模糊控制算法与PID控制技术相结合应用到多电机同步控制系统中,通过模糊控制算法在线调整PID参数.此控制系统在中山市天乙铜业热轧项目上使用,运行结果表明该方法能够大大改善系统的动态特性,提高了系统的稳定性.     

Dynamic characteristic analysis and lmi-basedh∞, controller design for a line of sight stabilization system

This paper is concerned with the design of an LMI (Linear Matrix Inequality)-basedH∞, controller for a line of sight (LOS) stabilization system and with its robustness performance. The linearization of the system is necessary to analyze various nonlinear characteristics, but the linearization entails modeling uncertainties which reduce its performance. In addition, the stability of the LOS can be adversely affected by angular velocity disturbances while the vehicle is moving. As the vehicle accelerates, all the factors that are ignored and simplified for the linearization tend to inhibit the performance of the system. The robustness in the face of these uncertainties needs to be assured. This paper employsH∞ control theory to address these problems and the LMI method to provide a suitable controller with minimal constraints for the system. Even though the system matrix does not have a full rank, the proposed method makes it possible to design aH∞ controller and to deal withR and S matrices for reducing the system order. It can be also shown that the proposed robust controller has a better disturbance attenuation and tracking performance. The LMI method is also used to enhance the applicability of the proposed reduced-orderH∞ controller for the system given. The LMI-basedH∞ controller has superior disturbance attenuation and reference input tracking performance, compared with that of the conventional controller under real disturbances.     

Design and implementation of a new fuzzy PID controller for networked control systems

This paper presents a practical network platform to design and implement a networked-based cascade control system linking a Smar Foundation Fieldbus (FF) controller (DFI-302) and a Siemens programmable logic controller (PLC-S7-315-2DP) through Industrial Ethernet to a laboratory pilot plant. In the presented network configuration, the Smar OPC tag browser and Siemens WinCC OPC Channel provide the communicating interface between the two controllers. The paper investigates the performance of a PID controller implemented in two different possible configurations of FF function block (FB) and networked control system (NCS) via a remote Siemens PLC. In the FB control system implementation, the desired set-point is provided by the Siemens Human-Machine Interface (HMI) software (i.e, WinCC) via an Ethernet Modbus link. While, in the NCS implementation, the cascade loop is realized in remote Siemens PLC station and the final element set-point is sent to the Smar FF station via Ethernet bus. A new fuzzy PID control strategy is then proposed to improve the control performances of the networked-based control systems due to an induced transmission delay degradation effect. The proposed strategy utilizes an innovative idea based on sectionalizing the error signal of the step response into three different functional zones. The supporting philosophy behind these three functional zones is to decompose the desired control objectives in terms of rising time, settling time and steady-state error measures maintained by an appropriate PID-type controller in each zone. Then, fuzzy membership factors are defined to configure the control signal on the basis of the fuzzy weighted PID outputs of all three zones. The obtained results illustrate the effectiveness of the proposed fuzzy PID control scheme in improving the performances of the implemented NCS for different transportation delays.     

基于PLC的PID自适应控制器在调速系统中的应用

介绍了由PLC控制实现的神经网络PID自适应控制器。实验表明,该技术对于提高控制精度是行之有效的,具有在调速系统中推广应用的价值。     

一种新的锁相测速方法

文中介绍了一种全新的精密数字锁相测量电机转速的方法和电路，此种方法不同于目前普遍采用的M／T测速方法。使用该方法，可以直接获得始终跟随电机速度变化的测速值，测速精度高、应用简单，目前已经成功地应用于笔者研制的交流伺服系统的反馈通道中。     

变论域模糊自整定PID内模控制在主汽温控制系统中的应用研究

火电厂主汽温控制系统具有大惯性、大延迟和时变等特性,采用常规PID串级控制方法难以获得满意的控制效果。通过引入1／1pade级数逼近纯滞后环节,将内模控制转换为常规PID控制器的参数的整定,运用变论域模糊控制原理来整定PID参数,从而实现了变论域模糊自整定PID内模控制。它充分综合了变论域模糊控制、内模控制、PID控制的优点。通过对锅炉过热蒸汽温度控制系统的仿真研究表明,变论域模糊自整定PID内模控制的控制效果优于常规的PID串级控制,它能适应对象参数的变化,具有较强的鲁棒性和自适应能力,控制品质好。     

关于最近邻聚类的RBF网络自整定PID控制算法的研究

针对采用传统PID控制一类非线性滞后系统难以获得满意的控制效果,提出基于RBF神经网络的PID控制参数自整定的方法.利用具有在线能力的最近邻聚类学习算法,训练RBF神经网络.并引入优化策略对聚类半径进行自动调整,以保证聚类的合理性,从而自适应调整系统的控制参数.仿真结果证明了该控制策略不仅能使非线性滞后系统具有良好的动态跟踪性能,而且具有很好的抗干扰能力和鲁棒性.     

Application of multi-objective controller to optimal tuning of PID gains for a hydraulic turbine regulating system using adaptive grid particle swam optimization

A hydraulic turbine regulating system (HTRS) is one of the most important components of hydropower plant, which plays a key role in maintaining safety, stability and economical operation of hydro-electrical installations. At present, the conventional PID controller is widely applied in the HTRS system for its practicability and robustness, and the primary problem with respect to this control law is how to optimally tune the parameters, i.e. the determination of PID controller gains for satisfactory performance. In this paper, a kind of multi-objective evolutionary algorithms, named adaptive grid particle swarm optimization (AGPSO) is applied to solve the PID gains tuning problem of the HTRS system. This newly AGPSO optimized method, which differs from a traditional one-single objective optimization method, is designed to take care of settling time and overshoot level simultaneously, in which a set of non-inferior alternatives solutions (i.e. Pareto solution) is generated. Furthermore, a fuzzy-based membership value assignment method is employed to choose the best compromise solution from the obtained Pareto set. An illustrative example associated with the best compromise solution for parameter tuning of the nonlinear HTRS system is introduced to verify the feasibility and the effectiveness of the proposed AGPSO-based optimization approach, as compared with two another prominent multi-objective algorithms, i.e. Non-dominated Sorting Genetic Algorithm II (NSGAII) and Strength Pareto Evolutionary Algorithm II (SPEAII), for the quality and diversity of obtained Pareto solutions set. Consequently, simulation results show that this AGPSO optimized approach outperforms than compared methods with higher efficiency and better quality no matter whether the HTRS system works under unload or load conditions.     

Instrumentation and control of a two-stage 4-bed silica gel + water adsorption cooling cum desalination system

This paper presents the instrumentation and control architecture for a laboratory based two-stage 4-bed silica gel + water adsorption system. The system consists of primarily two fluids: refrigerant (water vapour) and heat transfer fluid (water) flowing through various components. Heat input to the system is simulated using multiple heaters and ambient air is used as the heat sink. The laboratory setup incorporates a real time National Instruments (NI) controller to control several digital and analog valves, heaters, pumps and fans along with simultaneous data acquisition from various flow, pressure and temperature sensors. The paper also presents in detail the various automated and manual tasks required for successful operation of the system. Finally the system pressure and temperature dynamics are reported and its performance evaluated for various cycle times.     

Analysis of the mutual influence of contact spots in sliding of the periodic system of asperities on a viscoelastic base of the winkler type

The dependence of the contact characteristics and sliding friction coefficient on the density of the arrangement of contact spots is studied. To this end, the periodic contact problem of a system of asperities sliding on a viscoelastic base is considered. The main mechanism of the mutual effect of contact spots in the model in question manifests itself in the incomplete restoration of deformation on the free surface, with fairly dense arrangement of spots due to the imperfect elasticity of the base. The dependence is obtained of the friction coefficient on the spacing between asperities at various levels of effective loads and sliding velocities.     

Simultaneous measurement of strain and temperature using a hybrid local and distributed optical fiber sensing system

Structure multi-parameters measurement, such as strain, displacement, corrosion and temperature, is of the utmost importance for structural health monitoring. Meanwhile uncoupling method of temperature and strain has still a technical problem in structure sensing measurement. In this paper, we proposed a method for simultaneous measurement of strain and temperature using a hybrid local and distributed optical fiber sensing system. The principle of the method is investigated and then validated by the theoretical simulation experiments and tensile tests in laboratory. Furthermore, one experiment for internal force measurement of a smart stranded wire, under the interaction of temperature and strain, is also conducted in lab. The experimental results show that the strain and temperature can be well measured simultaneously by using one multi-signal optical fiber sensor.