直接转矩控制系统的稳定性问题和鲁棒控制器设计

直接转矩控制(DTC)系统的设计不依赖于感应电机的转子参数,但它的低速性能不好.研究发现,即使定子电阻测量得足够准确,根据定子磁链的电压电流模型设计的经典DTC系统的低速性能仍得不到改善.理论分析说明了这些问题存在的必然性,指出了DTC系统在转矩控制和稳定性之间存在的矛盾,给出了一种鲁棒控制器的设计方案.该方案同时使用了定子电阻和定子磁链的电流模型,当定子电阻和磁链模型出现误差时,表现出了好的鲁棒性.实验结果验证了系统的性能.     

基于DSP交流感应电机直接转矩模糊控制系统

介绍了基于DSP的交流感应电机直接转矩模糊控制系统的硬件：结构和软件设计。电压空间矢量的选择方法和故障诊断原理，并对系统的仿真结果和试验结果进行了分析。本系统具有动态相应快。调速精度宽。可靠性高等特点。     

Fuzzy logic controller design for spacecraft proximity operations

A Genetic Algorithms (GAs) based method is presented in this paper for concurrent design of rule sets and membership functions for a fuzzy logic controllers to be used in spacecraft proximity operations. The heuristic nature of fuzzy logic makes GAs a natural candidate for logic design in which both rule sets and membership functions are optimized simultaneously. The employment of GAs natural genetic operations provides a means to search in a complex system space that is difficult to described mathematically. A one-dimensional controller for spacecraft proximity operations is implemented for examination in detail. The expension of the algorithm for a 6 DOP controller is discussed.     

Fuzzy Petri net-based programmable logic controller

Programmable logic controllers (PLCs) are able to directly implement control sequences specified by means of standard languages such as Grafcet or formal models such as Petri nets. In the case of simple regulation problems between two steps it could be of great interest to introduce a notion of “fuzzy events” in order to denote a continuous evolution from one state to another. This could result from a linear interpolation between the commands attached to two control steps represented by two Petri net (PN) places. This paper is an attempt to develop fuzzy PN-based PLCs in a similar way as fuzzy controllers (regulators). Our approach is based on a combination of Petri nets with possibility theory (Petri nets with fuzzy markings)     

A new control method for Dynamic Voltage Restorer with asymmetrical inverter legs based on fuzzy logic controller

Dynamic Voltage Restorer (DVR) is used in power distribution system to protect sensitive loads in voltage disturbances. The performance of DVR is related to the adopted configuration and control strategy used for inverters. In this paper, an asymmetrical voltage-source inverter controlled with fuzzy logic method based on hysteresis controller, is used to improve operation of DVR to compensate voltage sag/swell. Simulation results using MATLAB/Simulink are presented to demonstrate the feasibility and the practicality of the proposed novel Dynamic Voltage Restorer topology. Total Harmonic Distortion (THD) is calculated. The simulation results of new DVR presented in this paper, are found quite satisfactory to eliminate voltage sag/swell.     

矿井提升机直接转矩控制系统转矩脉动最优控制

针对矿井提升机直接转矩控制系统低速段运行时存在转矩脉动过大的问题,提出了一种矿井提升机转矩脉动最优控制方法。该方法以预测模型为基础,采用零电压矢量注入方式进行最优电压矢量的占空比调整。整个占空比计算过程以转矩脉动最小为设计指标,采用在线计算的方式实时获得最优占空比。实验结果表明,该方法在低速时可有效减小电动机转矩脉动,获得优异的转矩控制性能。     

矿井提升机直接转矩控制系统转矩脉动最优控制

针对矿井提升机直接转矩控制系统低速段运行时存在转矩脉动过大的问题,提出了一种矿井提升机转矩脉动最优控制方法。该方法以预测模型为基础,采用零电压矢量注入方式进行最优电压矢量的占空比调整。整个占空比计算过程以转矩脉动最小为设计指标,采用在线计算的方式实时获得最优占空比。实验结果表明,该方法在低速时可有效减小电动机转矩脉动,获得优异的转矩控制性能。     

用于模糊控制器设计的遗传算法研究

将遗传操作用于模糊规则和控制器参数编码，实现输入变量的合理组合、模糊规则的获取和控制器参数的优化，设计者仅需给出一个运行遗传算法(GA)的个体适应度函数。同时将模拟退火算法(SA)用于优化控制器参数，这种GASA混合优化策略在模糊控制器设计中取得了良好的效果。实例表明了算法的有效性。     

Design of a novel adaptive TSK-fuzzy speed controller for use in direct torque control induction motor drives

This study proposes an adaptive Takagi-Sugeno-Kang-fuzzy (TSK-fuzzy) speed controller (ATFSC) for use in direct torque control (DTC) induction motor (IM) drives to improve their dynamic responses. The proposed controller consists of the TSK-fuzzy controller, which is used to approximate an ideal control law, and a compensated controller, which is constructed to compensate for the difference between the TSK-fuzzy controller and the ideal control law. Parameter variations and external load disturbances were considered during the design phase to ensure the robustness of the proposed scheme. The parameters of the TSK-fuzzy controller were adjusted online based on the adaptive rules derived in Lyapunov stability theory. The ATFSC, fuzzy control, and PI control schemes were experimentally investigated, using the root mean square error (RMSE) performance index to evaluate each scheme. The robustness of the proposed ATFSC was verified using simulations and experiments, which involved varying parameters and external load disturbances. The experimental results indicate that the ATFSC scheme outperformed the other control schemes.     

Fuzzy logic and slip controller of clutch and vibration for hybrid vehicle

This paper is the second part of the paper titled “Simulation and Control of Hybrid Electric Vehicles” published in IJCAS, Vol. 10(2)/2012 where the model predictive control has been built to handle the clutch engagement between the combustion engine and the electrical motor. In this research, a fuzzy logic and slip controller of clutch and vibration of the hybrid vehicle have been considered and tested as a second control strategy. The use of the fuzzy logic control can avoid the need of the complex and rigorous mathematical modeling since the fuzzy logic can work very successfully on the uncertain and imprecise information. The clutch slip controller is implemented in an experimental test vehicle for the critical vibration reduction.     

A multiregion fuzzy logic controller for nonlinear process control

Although a fuzzy logic controller is generally nonlinear, a PI-type fuzzy controller that uses only control error and change in control error is not able to detect the process nonlinearity and make a control move accordingly. In this paper, a multiregion fuzzy logic controller is proposed for nonlinear process control. Based on prior knowledge, the process to be controlled is divided into fuzzy regions such as high-gain, low-gain, large-time-constant, and small-time-constant. Then a fuzzy controller is designed based on the regional information. Using an auxiliary process variable to detect the process operating regions, the resulting multiregion fuzzy logic controller can give satisfactory performance in all regions. Rule combination and controller tuning are discussed. Application of the controller to pH control is demonstrated     

感应电动机直接转矩控制的稳定性分析

稳定性问题的研究在感应电动机直接转矩控制(DTC)中具有重要意义。现有文献主要关注恒转速情形,本文研究更接近实际的情况一一变转速下的DTC稳定性,引入状态反馈机制,首先给出定子磁链控制律存在的充分条件;然后在参考转矩大于或小于负载转矩的情形下,分别给出了转矩控制律存在的充分条件,最后以数值仿真验证了所提控制律的有效性,磁链和转矩相对于参考信号的波动确实是限定在一定容差范围内。     

Fuzzy Logic Control ASIC Chip

A fuzzy logic control VLSI chip,F100,for industry process real-time control has been designed and fabricated with 0.8μm CMOS technology.The chip has the features of simplicity,felexibility and generality.This paper presents the Fuzzy control inrerence method of the chip,its VLSI implementation,and testing esign consideration.     

Analytical method of PID controller design for parallel cascade control

An analytical method of PID controller design is proposed for parallel cascade control. Firstly, a general structure for parallel cascade control is proposed that takes both setpoint and load disturbance responses into account. Analytical tuning rules for the PID controllers are then derived for the general process model by employing the IMC design procedure. The proposed method offers a simple and effective way to obtain the PID controller rules for parallel cascade control system which takes into account the interaction between primary and secondary control loops. The simulation results illustrate the application of the proposed method and demonstrate its superiority compared to several alternatives.     

网络串级控制系统的事件触发控制器设计

为了减少有限网络带宽不必要的浪费,针对一类网络串级控制系统,首次引入事件触发机制,并在此基础上考虑系统的串级控制器设计问题,通过对系统稳定性进行分析,设计可靠的主控制器和副控制器.考虑信号传输造成的时延影响,首先建立带有事件触发机制的网络串级控制系统数学模型;然后利用李雅普诺夫稳定性理论和线性矩阵不等式技术,给出基于事件触发机制的系统稳定的充分条件,并且设计相应的主控制器和副控制器;最后通过仿真实例验证所提出的方法在网络串级控制系统中的有效性,即引入事件触发机制后,设计的主、副控制器使得在系统稳定的前提下,信号传输的间隔变大,从而减小网络的拥塞,提高网络带宽的有效利用率.     

Fuzzy torque distribution control for a parallel hybrid vehicle

A fuzzy torque distribution controller for energy management (and emission control) of a parallel hybrid electric vehicle is proposed. The proposed controller is implemented in terms of a hierarchical architecture which incorporates the mode of operation of the vehicle as well as empirical knowledge of energy flow in each mode. Moreover, the rule set for each mode of operation of the vehicle is designed in view of an overall energy management strategy that ranges from maximal emphasis on battery charge sustenance to complete reliance on the electrical power source. The proposed control system is evaluated via computational simulations under the FTP75 urban drive cycle. Simulation results reveal that the proposed fuzzy torque distribution strategy is effective over the entire operating range of the vehicle in terms of performance, fuel economy and emissions.     

Robust PID controller for flexible satellite attitude control under angular velocity and control torque constraint

A PID controller for flexible satellite attitude control with unknown perturbation is proposed in this paper. System inertia uncertainty, stochastic disturbance torque, and perturbation of flexible deformation are discussed, and the controller proposed in this paper is robust to these perturbations. A novel integral term is designed; hence the Lyapunov function structure is modified and the stability proof is simplified. The angular velocity constraint is discussed and a novel method to solve the angular velocity saturation issue is given. The control torque saturation issue is also taken into consideration. Stability for all conditions considered in this paper is proved by the Lyapunov method. The performance of the controller is demonstrated by numerical simulation.     

模糊PID控制器在自适应巡航控制系统中的应用

车辆的油门控制算法是自适应巡航控制系统(ACC：Adaptive Cruise Control)中的核心算法之一。这里采用的模糊PID算法(Fuzzy PID)是对常用的两输入单输出模糊控制算法的改进。通过使用Matlab／Simulink建立车辆动力学模型和控制器模型,对控制器的性能进行了仿真分析,验证了算法的合理性。     

Joint torque control by a direct feedback for industrial robots

Based on the experimental findings of Wu and Paul [17], two joints of an industrial robot have been redesigned and fabricated to include torque sensing capability by means of strain gauges. The resulting control systems reduced the effective frictional torques of the joints from 1072 oz.in to 33.5 oz.in. The stability of the closed-loop systems was analyzed by means of the describing function for limit cycles exhibited in the system, which can be removed by an insertion of phased-lead series compensating networks.