基于模糊逻辑的直线永磁同步电机直接推力控制

针对滞环DTC控制中转矩脉动大,效率低的问题,提出了动态生成定子参考磁链并基于模糊逻辑电压预测的DTC控制方法,建立了隐极式永磁直线同步电机推力直接控制的仿真模型,仿真及试验结果分析证实,与传统的DTC方法相比,稳态运行时的磁链、推力脉动得到明显的改善,且提高了系统的效率.     

基于MRAS的永磁同步电机直接转矩控制系统的研究

研究了一种基于模型参考自适应无速度传感器的永磁同步电机直接转矩控制系统:将永磁同步电机的磁链模型作为参考模型,估算的定子磁链模型作为可调模型,设计了自适应定律对电机的转速与定子电阻同时进行跟踪辨识,使用空间电压矢量调制技术组成了永磁同步电机无速度传感器直接转矩控制系统。仿真实验结果表明该系统获得了近似圆形的定子磁链,在转速与转矩变化时均能准确的估算出电机转速,具有良好的动、静态性能。     

基于定子磁链定向的异步电机无速度传感器矢量控制系统的仿真分析

本文介绍了一种基于定子磁链定向的异步电机无速度传感器矢量控制系统，推导出异步电机在定子磁链定向下的数学模型，并依此建立控制系统，最后给出了系统的仿真策略和调速性能的仿真结果。     

按定子磁场定向控制系统中定子电阻的影响分析

在研究按定子磁场定向控制系统中，采用定子磁链观测器控制磁链，认为定子电阻是恒定不变的。而在实际电机运行过程中定子电阻由于发热等条件因素的影响会一直变化。本文通过讨论定子电阻的变化对控制系统性能的影响的理论分析，指出定子电阻在按定子磁场定向的控制系统中低频时对系统影响较大，同时应用Matlab的simulink进行模仿定子电阻变化相关仿真。     

电网故障时双馈风力发电机励磁改进控制策略

双馈风力发电机（DFIG）在风能捕获过程中,传统的定子磁链定向控制都假定电网上的电压恒定不变,定子磁链也恒定不变,没有考虑定子励磁电流的动态响应过程,这个误差在电网故障时会对系统产生极不稳定的作用。为此应考虑该响应过程,对控制檳型进行修正,提出一种应对电网电压跌落时的励磁改迸策略,即在建立转子侧变换器控制模型时,把反映励磁电流过渡过程的定子电压变化量考虑进来。通过推导定子磁场定向下的转子电压方程,搭建定子磁链定向矢量控制模型,经过仿真结果比较,说明在加入励磁补偿电压项后,风电系统在应对电网电压故障时的电流控制性能得到明显改善,有效提升了系统的低电压穿越能力。     

感应电动机调速系统的新型线性化解耦控制方法

本文提出了一种新型感应电动机调速系统的线性化解耦控制方法，以定子磁链和电磁转矩作为感应电动机数学模型的输出，给出了感应电动机逆系统的动态方程，利用得到的逆系统将调速系统解耦为电磁转矩和定子磁链两个线性子系统。在此基础上，对整个调速系统进行了综合，给出了调速系统的原理框图，实现了电磁转矩和定子磁链的动态解耦控制。仿真实验验证了理论分析的正确性和控制方案的可行性。     

一种基于二阶广义积分器的永磁同步电机定子磁链观测方法

永磁同步电机的定子磁链观测技术是实现直接转矩控制的基础。传统的电压模型定子磁链观测器中存在着直流偏置、积分饱和等问题,因此本文采用改进的二阶广义积分器(improved second-order generalized integrator, ISOGI)代替电压模型中的纯积分器,进而得到一种改进的基于ISOGI的定子磁链观测器。与传统的电压模型定子磁链观测器相比,该观测器有效提高了定子磁链的观测精度。仿真和实验结果表明基于ISOGI的定子磁链观测器是可行的。本文网络版地址：http：//www.eepw.com.cn/article/276359.htm     

双馈风力发电机功率解耦控制的研究

介绍双馈风力发电机的基本原理,利用矢量控制并结合定子磁场定向的矢量控制,建立基于Matlab的双闭环控制系统仿真模型。为了更为准确地实现定子磁场定向并考虑到定子绕组电阻对磁场定向的影响,采用改进型的定予磁链观测模型。通过仿真验证了采用改进型定子磁场定向的双馈风力发电控制系统,实现了有功功率和无功功率解耦。     

基于垂直轴双馈风力发电系统的仿真研究

以垂直轴风轮（VAWT）和双馈感应发电机（DFIG）为研究对象,建立了包括风力机模型、传动系统模型和双馈电机模型的垂直轴双馈风力发电系统的数学模型及结构,采用双馈电机定子磁链定向前馈解耦控制,使得电机的有功分量和无功分量可以分别得到控制。运用Matlab/Simulink建立了系统仿真模型,对定子磁链定向前馈解耦控制策...     

电流驱动按定子和气隙磁链定向的矢量控制

按转子磁链定向的矢量控制系统与转子参数有关,使得交流调速系统的性能受到影响。本文采用电流输出控制型逆变器,按定子磁链和气隙磁链定向的矢量控制,推导解耦控制方程,附加去耦项,实现系统的彻底解耦控制,磁链检测和转矩检测不含转子参数,仿真结果表明,新系统提高了磁场定向的准确性和解耦能力,改善闭环控制的动态性能和鲁棒性。     

基于MPPT的变速恒频双馈风力发电系统控制策略

充分利用风能是风力发电控制的主要目的之一,为达此目的,本文基于风力机特性和双馈风力发电机的数学模型,提出了一种不依赖于风速测量来实现双馈风力发电系统最大功率点追踪(MPPT)控制的策略。该策略应用定子磁链定向矢量控制技术,对双馈发电机进行有功功率和无功功率的解耦控制,然后通过对发电机输出有功功率进行控制来间接得到与风速相对应的最佳叶尖速比和最优转速,从而实现最大功率点追踪(MPPT)控制。仿真结果证实了基于该方法,双馈风力发电系统在风速变化过程中能自动寻找并追随最大功率点,且控制相对简单,运行可靠,有较高的实用价值。     

Modeling and Control of Brushless Doubly-Fed Induction Generators in Wind Energy Applications

The development of the brushless doubly-fed induction generator (BDFIG) system and flexible power flow controller for the wind energy conversion is proposed in this paper. The system employs two cascaded induction machines to eliminate the brushes and copper rings in the traditional DFIG. The dynamic model of BDFIG with two machines' rotor electromechanically interconnected is presented and the control strategy for flexible power flow control is developed. The independent control of the active and reactive power flows is achieved by means of a four quadrant power converter under the closed-loop stator flux oriented control scheme. The experimental results obtained verify the proposed controller scheme, which allows wide operational range and reactive power control.     

一种具有容错功能的无轴承薄片电机的原理及其实现

本文研究了一种可以实现容错功能的无轴承薄片电机的工作原理和结构设计。详细推导了当无轴承薄片电机在采用单绕组结构并采用定子绕组电流功率最优约束下的径向悬浮力和转矩的数学模型,并由此推导出了电机在绕组完整和绕组故障时的不同定子电流模型,同时给出了相应的控制策略和样机系统设计。实验样机调试结果表明：采用单绕组结构的无轴承薄片电机成功实现了转子在径向、轴向和扭转方向上的5自由度全悬浮。     

电动汽车用双向DC-DC变换器最优效率控制研究

针对电动汽车复合能源系统中隔离双向DC-DC变换器采用传统单移相控制峰值电流和功率损耗过大的缺陷,提出一种基于双重移相控制的最优效率控制策略。首先分析了双重移相控制工作原理,建立了隔离双向DC-DC变换器功率损耗模型,然后分析推导了隔离双向DC-DC变换器功率损耗最小的条件及最优效率控制的实现方案,使双向DC-DC变换器工作在功率损耗最小状态,从而使系统效率实现最大化。最后通过实验验证了最优效率控制的正确性和优越性。     

无刷双馈风力发电控制策略研究

本文研究了为实现最大风能捕获和有功、无功功率解耦控制的无刷双馈发电机的定子磁链定向矢量控制策略,并建立了变速恒频双馈风力发电系统的仿真模型,通过仿真验证了理论、模型和控制策略的正确性、可行性。     

Sensorless DTC-SVM for Induction Motor Driven by a Matrix Converter Using a Parameter Estimation Strategy

This paper presents a new direct torque controlled space vector modulated method to improve the sensorless performance of matrix converter drives using a parameter estimation scheme. The flux and torque error are geometrically combined in a new flux leakage vector to make a stator command voltage vector in a deadbeat manner. A new sensorless method of estimating the rotor speed, flux, stator resistance, and rotor resistance is derived and verified with experimental results. Common terms in the error dynamics are utilized to find a simpler error model involving some auxiliary variables. Using this error model, the state estimation problem is converted into a parameter estimation problem assuming the rotor speed is constant. The proposed adaptive schemes are determined so that the whole system is stable in the sense of Lyapunov. The effectiveness of the proposed algorithm is verified by experiments.     

An Adaptive Sliding Stator Flux Observer for a Direct-Torque-Controlled IPM Synchronous Motor Drive

This paper focuses on performance improvements of the stator flux estimation for a direct-torque-controlled interior permanent magnet synchronous motor drive. In this paper, an adaptive sliding observer is presented to estimate the stator flux linkage based on the motor current model. The experimental results show that the proposed observer has been able to deliver more accurate estimation than an open-loop estimator both in the steady state and during transients. The observer has better dynamic behavior, disturbance resistance, and high-accuracy estimation ability. With the integrated flux observer, the drive system can operate at very low speed down to 10 r/min (0.33 Hz) with half full load.     

A new stator resistance tuning method for stator-flux-orientedvector-controlled induction motor drive

Field-oriented-controlled induction motor drives have been widely used over the last several years. Conventional direct stator-flux-oriented control schemes have the disadvantage of poor performance in the low-speed operating area when the stator flux is calculated using the voltage model, due to the stator resistance uncertainties and variations. In this paper, a new closed-loop stator-flux estimation method for a stator-flux-oriented vector-controlled induction motor drive is presented in which the stator resistance value is updated during operation. This method is based on a simple algorithm capable of running in a low-cost microcontroller, which is derived from the dynamic model of the induction machine. The effects of stator resistance detuning, especially in the low-speed operating region, are investigated and simulation results are shown. The motor drive system as well as the control logic and the resistance estimator are simulated and characteristic simulation results are derived. In addition, the proposed control scheme is experimentally implemented and some characteristic experimental results are shown. The simulation as well as the experimental results reveal that the proposed method is able to obtain precise flux and torque control, even for very low operating frequencies