Transient and steady-state temperature distribution in monolayer-coated carbide cutting tool

Direct torque control (DTC) of permanent magnet synchronous motor (PMSM) drives is receiving increasing attention due to important advantages, such as fast dynamic and low dependence on motor parameters. However, conventional DTC scheme, based on comparators and the switching table, suffers from large torque and flux ripples. In this paper, two intelligent approaches are proposed in order to improve DTC performance. The first approach is based on two adaptive fuzzy logic controllers (AFLC). The first AFLC replaces the conventional comparators and switching table and the second AFLC adjusts in real time the outer loop PI parameters. In the second approach, particle swarm optimization (PSO) is used as another alternative to adjust the PI parameters. Simulation and experimental results demonstrate the effectiveness of the proposed intelligent techniques. Besides, the system associated with these techniques can effectively reduce flux and torque ripples with better dynamic and steady state performance. Quantitatively, PSO-based DTC approach reduces greatly flux and torque ripples. Further, PSO-based approach maintains a constant switching frequency which improves the PMSM drive system control performance.     

基于空间矢量的同步磁阻电机直接转矩控制

针对传统直接转矩控制由于采用滞环比较器对磁链和转矩进行直接控制,导致磁链、转矩脉动较大和开关频率不固定等问题,对同步磁阻电机直接转矩控制进行了研究,开展了直接转矩控制的基本原理分析,根据同步磁阻电机的数学模型,提出了一种定子磁场定向下磁链和转矩双闭环PI控制结构的直接转矩控制方案,采用空间矢量调制策略,克服了传统直接转矩控制的缺点。利用Matlab/Simulink搭建了两种直接转矩控制方案的仿真模型,并利用基于d SPACE的实验平台对该方案的低速性能进行实验研究,研究结果表明:相较于传统的直接转矩控制,该方案能明显减小电机的转矩脉动并且能保持开关频率恒定,能使电机在低速范围内具有良好的动态性能,并且使得电机在低速范围内稳定运行,证明了该方案的可行性和有效性。     

Real-Time Simulator based hybrid control of DFIG-WES

This paper presents the analysis and design of recurrent neural network (RNN) and proportional and integral(PI) controller based hybrid control(HC) of doubly fed induction generator (DFIG). The proposed HC shows the quick dynamic and good transient response during the sudden changes in wind speed as well as generator speed. Further performance of proposed hybrid controller has been analyzed independently with RNN and PI control as its components. The HC along with RNN gives effective performance compared to conventional DTC (CDTC) and PI DTC in terms of flux ripples,torque ripples and settling time. The proposed technique is implemented in real-time simulator (RTS) based OPAL-RT and MATLAB/SIMULINK environment at a rating of 5.5 KW system under steeply and randomly change in wind velocity.     

永磁同步电机无差拍直接转矩控制系统研究

针对传统永磁同步电机(PMSM)直接转矩控制(DTC)中存在的磁链、转矩脉动大、开关频率不固定等问题,提出了一种永磁同步电机的无差拍直接转矩控制(DB-DTC)方法,在离散化电机方程基础上利用无差拍控制原理计算出电压矢量,并结合了空间矢量调制技术(SVM)产生开关信号控制电机运行。同时针对离散系统运算耗时所带来的控制周期的误差,进一步基于永磁体同步电机数学模型,提出了一种电流观测器以预测下一控制周期的电流值,目的是准确估计定子磁链和转矩。研究结果表明,所提出的PMSM DB-DTC不仅继承了传统DTC动态响应快的优点,而且能极大程度地削弱定子磁链和转矩的脉动,该系统具有良好的动静态性能,电流观测器能预测定子电流,确保了PMSM DB-DTC系统的控制精度。     

Speed sensorless model predictive current control of doubly-fed induction machine drive using model reference adaptive system

This paper presents a speed sensorless control scheme named as finite control set-model predictive current control (FCS-MPCC) using a modified fictitious ohmic quantity (R) based model reference adaptive system (MRAS) for grid-connected doubly-fed induction machine (DFIM) drive. The variables of the reference model of this speed sensorless scheme (R-MRAS) are represented in stationary reference frame while those for the adaptive model are denoted in synchronously rotating reference frame. The sensorless formulation thus obtained is completely independent of any stator/rotor resistance terms. The scheme is also devoid of any stator/rotor flux estimation. Moreover, the intuitiveness of FCS-MPCC brings in additional flexibility in comparison to the conventional control techniques like field oriented control (FOC) and direct torque control (DTC). The overall scheme demonstrates faster execution time than FOC/DTC based control of DFIM drive. The proposed control algorithm is simulated and tested for limited speed range application in MATLAB/Simulink. The validation of simulation results are further done by experimentation on a dSPACE-1103 based DFIM laboratory setup.     

异步电机全阶自适应磁链观测

针对传统的直接转矩控制系统采用纯积分的电压模型作为磁链观测器,存在着误差积累以及直流偏移,导致电流和转矩的波动问题,提出了一种基于定子磁链的自适应全阶观测器的直接转矩控制系统。     

基于模糊自适应控制的无轴承异步电动机SVM-DTC运行控制

提出了一种基于模糊自适应控制的无轴承异步电动机的空间矢量调制的直接转矩控制策略。通过模糊控制算法得到磁链和转矩的控制电压分量,实现了两个电压矢量的实时调整,解决了采用传统PI控制器所带来的脉动较大的问题。并利用Matlab/simulink仿真软件,分别建立基于模糊自适应控制的空间矢量调制的直接转矩控制系统和双PI控制的空间矢量调制的直接转矩控制系统模型。仿真结果表明,改进后的算法可以更好地抑制转矩、磁链的脉动及转速超调,提高系统的动态性能。     

一种提高转矩控制系统性能的新型控制器

在传统异步电机转矩控制策略的基础上,将自抗扰控制器 (ADRC) 的核心环节--扩张的状态观测器 (ESO)引入速度环调节器,构造了一种基于ESO的新型控制器.建立了常规转矩控制系统和采用新型控制器转矩控制系统的仿真模型,并对仿真结果进行分析比较.仿真结果表明,采用新型控制器能有效改善直接转矩控制系统的性能,提高了系统运行的可靠性.新型控制器结构简单,易于实现.     

Sliding-mode control of a six-phase series/parallel connected two induction motors drive

In this paper, a parallel configuration is proposed for two quasi six-phase induction motors (QIMs) to feed them from a single six-phase voltage source inverter (VSI). A direct torque control (DTC) based on input–output feedback linearization (IOFL) combined with sliding mode (SM) control is used for each QIM in stationary reference frame. In addition, an adaptive scheme is employed to solve the motor resistances mismatching problem. The effectiveness and capability of the proposed method are shown by practical results obtained for two QIMs in series/parallel connections supplied from a single VSI. The decoupling control of QIMs and the feasibility of their torque and flux control are investigated. Moreover, a complete comparison between series and parallel connections of two QIMs is given.     

基于空间矢量无速度传感器感应电机的直接转矩控制

直接转矩控制(DTC)对于异步电机而言，它能产生快速及好的鲁棒性响应。介绍了一种新的对于无速度感应电动机基于空间矢量(SVM)模型的直接转矩和磁链控制，它能降低稳态时力矩、磁链和速度的波动，在全速度范围无速度传感应用中将产生更好的稳态性能的同时保留DTC的暂态优点。仿真结果显示，该方法有着比传统的DTC更好的性能。     

基于Matlab/Simulink的异步电机直接转矩控制系统仿真

在异步电动机数学模型的基础之上,利用MATLAB／Simulink软件构建了一个异步电动机直接转矩控制调速系统。对仿真模型中的定子磁链观测器模块进行了描述,并简要说明了空间电压矢量对磁链和转矩的作用及影响。通过对异步电动机进行仿真实验,得到电压、电流、转速、转矩以及磁链的仿真波形。     

电动车用交流异步电机宽速域控制策略

针对异步电机转速控制中传统电压型磁链观测方法引起的直流偏移问题,设计了通过截止频率实时调整的饱和反馈低通滤波磁链观测器。为解决传统弱磁计算不准确问题,提出了一种恒压弱磁控制方法,有效地实现了恒转矩区和弱磁区的平稳调速。在建立基于转子磁场定向的交流异步电机矢量控制数学模型的基础上,制定了一种综合考虑恒转矩区和弱磁区的基于MRAS系统的转速控制策略。对所提出的控制策略进行了仿真与实验,结果表明系统获得了良好的控制效果,验证了算法的合理性和有效性。     

基于MRAS的无速度传感器异步电机控制

为研究无速度传感器直接转矩控制系统中对速度的估算和控制,建立了一种基于模型参考自适应（MRAS）系统原理的速度磁链自适应观测器。它以定子电流和定子磁链为状态变量,构建全阶观测器为可调模型,电机本身为参考模型,把磁链观测和速度辨识结合起来,直接把定子磁链观测值应用于直接转矩控制算法中,定义了李亚普诺夫函数,并根据其稳定性理论确定了速度自适应律。通过Matlab／Simlink软件进行了仿真。仿真结果表明,该系统对电机定子磁链的观测精度高,速度运算较准确,在全速范围内能保持较高的性能。     

电主轴直接转矩控制系统的仿真研究

首先介绍了直接转矩控制的六边形和近似圆形磁链轨迹的控制方案,给出了高速电主轴直接转矩控制系统的结构及其工作原理;然后详细阐述了转矩调节器的容差选择、电压空间矢量的选择和高低速调节方案的选择;使用Madab/Simulink仿真工具,完成了六边形和近似圆形磁链轨迹的直接转矩控制系统的仿真研究;仿真结果显示,将直接转矩控制...     

基于自适应全阶磁链观测器的直接转矩控制系统

基于模型参考自适应理论，采用自适应全阶磁链观测器观测定子磁链和辨识转速，并结合模糊控制，利用Matlab／Simulink构建了无速度传感器直接转矩控制系统。     

Fuzzy-Super twisting control implementation of battery/super capacitor for electric vehicles

The present paper deals with a real-time implementation of a novel Fuzzy logic energy management strategy (EMS), applied to a battery–super capacitor hybrid energy system and associated with a permanent magnet synchronous motor (PMSM) which emulates the traction part of an electric vehicle (EV). On the sources side, the fuzzy logic supervisor acts in a smart way to permute smoothly between the various operations modes via an efficient power frequency splitting. In addition, it permits a quite regulation of both the DC bus and the super-capacitor (SC) voltages regardless of the speed profile variations to ensure an optimal power flow to the load and to keep the SC operation in a safe voltage range while providing or absorbing power in transients. On the traction side, a second order sliding mode control called ‘super-twisting’ (ST), associated with a space vector modulation (SVM) strategy is applied to ensure both decoupled torque and flux control under low torque and flux ripples. The assessment of the proposed control techniques is conducted on a small-scale battery/SC/PMSM system, controlled via two dSPACE1104 cards. The obtained experimental results show a smooth operation of the whole system, where the proposed Fuzzy logic supervisor succeeds to provide fast and high performances under different speed levels and ensures the proper functioning of each source while respecting its dynamics. Furthermore, the second order sliding mode controller shows good dynamic performances, where the system arrives to track perfectly the speed profile, under tolerable torque and flux ripples.     

新型自适应速度观测器在异步电机直接转矩控制系统中的应用

实现高性能直接转矩控制系统的重要环节是准确地观测异步电机的定子磁链，本文将一种新型的速度自适应磁链闭环观测器，应用于直接转矩控制系统中，取代了传统的积分器，理论证明该系统是超稳定系统，仿真与实验表明，该方案对电机磁链的观测精度高，对电机参数的鲁棒性好，同时基于磁链观测器所设计的速度自适应辨识方案准确性好，收敛速度快，使系统在较低转速下仍能保持优良的性能，本系统针对1．1kW异步电机，采用数字信号处理器DSP（TMS320C32）进行了数字化实现，实时控制软件是采用C和汇编语言混合编程实现的。     

矩阵变换器驱动永磁同步电机的模型预测转矩控制（英文）

针对三相永磁同步电机(PMSM)系统,采用矩阵变换器(MC)驱动方式,设计了模型预测转矩控制(MPTC)的策略。采用MC驱动替换常规交-直-交变换器,以提高系统输入侧的功率因数(PF),而MPTC预测电压空间矢量保证了系统有良好的转矩和磁链控制效果。在建立MC驱动PMSM系统的数学模型的基础上,给出了MC驱动PMSM的MPTC设计方法。MPTC策略不仅使MC驱动的PMSM系统稳定运行,具有较好的转矩和磁链控制效果,而且输入侧PF能够达到1。与直接转矩控制(DTC)策略相比较,该策略具有更强的抗负载干扰能力和跟踪给定转速变化的能力。最后,通过仿真实验验证了该方法的正确性和有效性。     

Modeling and output tracking of transverse flux permanent magnet machines using high gain observer and RBF neural network

This paper deals with modeling and adaptive output tracking of a transverse flux permanent magnet machine as a nonlinear system with unknown nonlinearities by utilizing high gain observer and radial basis function networks. The proposed model is developed based on computing the permeance between rotor and stator using quasiflux tubes. Based on this model, the techniques of feedback linearization and H_∞ control are used to design an adaptive control law for compensating the unknown nonlinear parts, such as the effect of cogging torque, as a disturbance is decreased onto the rotor angle and angular velocity tracking performances. Finally, the capability of the proposed method in tracking both the angle and the angular velocity is shown in the simulation results.     

直接转矩控制系统定子电阻观测的研究

目前直接转矩控制系统是控制感应电动机的一种新兴技术,它不需要复杂的控制算法就可以得到异步电动机的磁链和转矩．但是感应电动机定子电阻的变化影响直接转矩控制系统的低速性能,因此调节电动机的定子电阻是非常重要的．本文综述了直接转矩控制系统定子电阻观测方法的研究现状,阐述了定子电阻不同的观测方法,并展望了直接转矩控制技术的应用前景．