直驱式永磁风力发电机软并网与功率调节的控制集成

为实现直驱式永磁同步风力发电机无冲击并网与风能最大跟踪控制, 设计了一种软并网与功率调节一体化的控制集成装置. 基于广义功角特性, 提出了一种对逆变器输出功率进行直接控制, 从而实现最大风能跟踪的控制策略. 新的控制策略可使发电机的转速按所期待的动态运动, 因而具有良好的静态与动态性能. 另外, 该控制律中对电机参数具有很强的鲁棒性, 因而该控制器能适应各种不同参数的同步风力发电机, 成为同步风力发电并网与功率调节的独立装置.     

基于精确线性化的永磁同步风力发电机滑模控制

针对直驱永磁同步风力发电机的最佳转速跟踪控制,提出了基于精确线性化模型的滑模控制策略及其设计方法,运用Matlab/Simulink建立了直驱型永磁同步风力发电机的仿真模型,并对不同风况下运行的机组进行了仿真分析。结果表明该控制器能在较宽的风速范围内有效提高系统的鲁棒性。     

基于精确线性化的永磁同步风力发电机滑模控制

针对直驱永磁同步风力发电机的最佳转速跟踪控制,提出了基于精确线性化模型的滑模控制策略及其设计方法,运用Matlab/Simulink建立了直驱型永磁同步风力发电机的仿真模型,并对不同风况下运行的机组进行了仿真分析。结果表明该控制器能在较宽的风速范围内有效提高系统的鲁棒性。     

永磁同步风力发电机组的滑模控制

风能是一种可再生的清洁能源。风力发电机组由于空气动力学的不确定性和电力电子模型的复杂性,使系统具有复杂多变量非线性系统的特点。该文根据风轮的空气动力学特性和永磁同步发电机的矢量控制理论,采用滑模变结构控制策略,把风力永磁同步发电机组的性能指标作为滑模函数,通过合理选择系数来实现对其速度控制环和位置控制环进行滑模变结构控制设计,能使系统快速、平稳且无抖动地进入滑动模态面,从而保证风力发电机组良好的动态特性、有效抑制系统的扰动、兼顾最大功率系数和良好的发电质量。     

双馈风力发电系统最大风能追踪滑模变结构控制

针对如何实现双馈风力发电机最大风能追踪(MPPT)问题, 本文采用滑模变结构控制原理和定子磁场定向矢量控制原理, 提出了滑模控制的最大风能追踪方案. 为此首先简要的介绍了定子磁场定向矢量控制的原理, 然后根据风机模型的非线性提出了滑模控制最大风能追踪方案. 此方法实现了双馈风力发电机的有功, 无功功率的解耦控制. 提高风力发电系统转速控制的抗干扰性, 实现了变速恒频控制和最大功率点跟踪的快速和稳定控制, 从而捕 获更多的风能. 最后仿真结果验证本文提出的控制策略的正确性和有效性.     

风能转换系统执行器故障重构与容错控制

针对风能转换系统中执行器故障,论文提出了一种新型的主动容错控制策略.设计滑模故障观测器,实时动态采集执行器故障前后数据信息,对执行器故障进行重构,达到故障诊断的目的.通过补偿控制,保证了滑模控制器对风能转换系统的可靠控制输入,以达到对执行器故障主动容错的功能.仿真结果表明,滑模故障观测器模块能够实时精确地重构风能转换系统执行器故障,主动补偿容错控制器在不影响风能转换系统动态性能的情况下,仍能实现系统的最大风能的捕获.     

永磁直驱风力发电系统机侧控制策略研究

最大功率跟踪一直是风力发电控制策略研究的热点和难点,本文首先介绍永磁直驱风力发电系统背靠背变流器的基本拓扑结构,然后在建立双Y移30°六相永磁同步发电机数学模型的基础上,基于id=0的转子磁场定向,设计了转速外环电流内环的双闭环控制器。通过监测风速变化实时调整电机转速,以达到最大风能捕获的目的。实验结果进一步验证了该控制策略的正确性与可行性。     

基于负载观测的最大风能跟踪控制

研究风力发电机风能优化控制问题,由于风轮系统存在非线性,为了实现最大化捕获风能,设计了基于耗散系统理论框架的L2范数优化鲁棒速度控制器,有效克服系统参数变化带来的系统不确定性的影响;并为克服大惯量风轮转矩变化对风速跟踪的不良影响,设计了一个负载观测器,在线观测风轮转矩,对风轮转矩的动态变化进行补偿,实现了风速动态跟踪控制,提高了风能转换效率.以1.5MW直驱永磁风电机组作为研究对象,进行了仿真,结果表明,控制策略可以有效地实现最大风能跟踪控制,并且对于干扰具有较强的鲁棒性,为风力发电优化设计提供了依据.     

模糊控制器在最优风能捕捉系统中的应用

本文以西门子系列的PLC和新型的复合励磁稀土永磁同步发电机作为硬件基础,通过爬山算法并结合模糊控制设计出一套最优风能捕捉的系统方案,使该系统在没有精确数学模型的情况下仍能得到比较满意的控制效果,在风场的集散控制系统中具有较高的实用价值.     

基于径向基函数神经网络故障观测器的风能转换系统容错控制器设计

针对风能转换系统执行器部分失效故障,提出了一种新型的主动容错控制策略.应用径向基函数(radial basis function,RBF)自适应神经网络,根据系统状态观测值对执行器故障进行在线重构,基于该重构故障,设计滑模容错控制器切换增益,实现风能转换系统故障诊断与容错控制律在线整定,并进行稳定性证明.仿真结果表明,执行器发生故障时系统的功率系数和叶尖速比均能保持在最优值,从而实现额定风速以下的最大风能捕获.     

A rotor speed estimation algorithm in variable speed permanent magnet synchronous generator wind energy conversion system

A rotor speed estimation algorithm in a direct vector controlled permanent magnet synchronous generator wind energy conversion system is proposed. The proposed method is based on a simple equation obtained from the flux model of the machine and contains only stator flux and current. Constant gain recursive least squares estimator is used for implementing the speed estimation algorithm. Rotor position information used for coordinate transformation is computed using the estimated speed. Stator flux information required by the speed estimator is obtained using the stator voltage equation by implementing a programmable low pass filter. The estimated speed is used as the feedback signal for the speed control loop of the vector controlled machine side converter control system whose command speed is obtained from a wind speed sensorless maximum power point tracking controller, thus, we obtain a complete rotor speed and wind speed sensorless permanent magnet synchronous generator wind energy conversion system. Simulation is carried out to validate the performance of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.     

永磁直驱风电机组的建模与仿真

针对永磁直驱风力发电机组建立了包括风力机、传动系统、永磁同步发电机、变流器各部分的数学模型;根据最大风能跟踪原理,提出了发电机侧和电网侧变流器的控制策略;在Matlab/Simulink仿真环境下建立了永磁直驱风电机组的仿真模型,对风速阶跃变化时机组运行情况进行了仿真。仿真结果验证了所提出控制策略的正确性和模型的合理性。     

Fully sensorless robust control of variable-speed wind turbines for efficiency maximization

This paper focuses on a sensorless robust power generation control strategy for a variable speed wind energy conversion system based on a permanent magnet synchronous generator. The proposed control strategy combines a robust observer of the aerodynamic torque, a simple technique for extracting rotor position using electrical signals, a robust observer of rotor speed, and a sliding mode based field oriented control strategy. The robust vanishing of the observation errors and tracking error is proved. Reported numerical simulations show that the proposed control policy is effective in terms of efficiency maximization and it is robust with respect to bounded parameter variations affecting the mechanical system.     

开关磁阻风力发电系统研究

针对传统的基于异步发电机、双馈发电机和永磁同步发电机的风力发电系统稳定性较差,风力发电系统的实验研究需要诸多条件、不易实现的问题,提出了一种在不具备风场实验条件情况下进行基于开关磁阻发电机的风力发电系统研究的方法,即采用直流电动机模拟风力机来进行开关磁阻发电系统的实验。建立了直流电动机模拟风力机的仿真模型,介绍了基于该模型的开关磁阻风力发电系统最大输出功率闭环控制方案。仿真结果表明,该控制方案能使所建立的发电系统快速进行功率调节并进入稳态工作。     

An improved model predictive control of low voltage ride through in a permanent magnet synchronous generator in wind turbine systems

This research investigates a wind energy conversion system based on a permanent magnet synchronous generator (PMSG). In addition, a model predictive control (MPC) is proposed for the PMSG in normal and fault conditions. The most efficient mode of the control algorithm is found for maximum power point tracking in normal conditions and fast dynamic response in fault conditions following the selection of the optimum voltage vector. This method prevents a sudden increase in the DC‐link voltage by storing the active power in the generator rotor inertia. Moreover, during the low voltage, the grid code adoption of the reactive current is injected into the grid side. The performance of the proposed control scheme is evaluated for a wind power generator using MATLAB software. The simulation results demonstrate that the proposed method can safeguard the DC‐link during the fault.     

无速度传感器PMSM混沌运动的非奇异快速终端滑模控制

针对永磁同步电机调速系统中速度传感器存在安装缺陷及在某些特定的参数下电机会呈现混沌特性,提出了无速度传感器永磁同步电机滑模控制混沌抑制方法．在无速度传感器运行的永磁同步电机矢量控制调速系统基本框架下,采用非奇异快速终端滑模控制方法来抑制电机的混沌运动．首先在永磁同步电机的混沌模型基础上通过仿真验证了混沌现象的存在;然后利用扩张状态观测器（ESO）估计转速,构成无速度传感器永磁同步电机矢量控制系统;在此基础上设计了非奇异快速终端滑模控制器,当电机在某些参数条件下呈现混沌现象,即刻通过控制器的切入来抑制永磁同步电机的混沌运动．最后通过仿真验证该方法的有效性,保证电机运行稳定和可靠.     

Sensorless adaptive output feedback control of wind energy systems with PMS generators

This paper addresses the problem of controlling wind energy conversion (WEC) systems involving permanent magnet synchronous generator (PMSG) fed by IGBT-based buck-to-buck rectifier–inverter. The prime control objective is to maximize wind energy extraction which cannot be achieved without letting the wind turbine rotor operate in variable-speed mode. Interestingly, the present study features the achievement of the above energetic goal without resorting to sensors of wind velocity, PMSG speed and load torque. To this end, an adaptive output-feedback control strategy devoid of any mechanical sensor is developed (called sensorless), based on the nonlinear model of the whole controlled system and only using electrical variables measurements. This control strategy involves: (i) a sensorless online reference-speed optimizer designed using the turbine power characteristic to meet the maximum power point tracking (MPPT) requirement; (ii) a nonlinear speed regulator designed by using the backstepping technique; (iii) a sensorless interconnected adaptive state observer providing online estimates of the rotor position as well as speed and load/turbine torque. The proposed output-feedback control strategy is backed by a formal analysis showing that all control objectives are actually achieved. Several simulations show that the control strategy enjoys additional robustness properties.     

永磁同步风力发电机组控制策略的仿真研究

针对直驱式风电机组全功率变流器双PWM背靠背式的拓扑结构,利用Matlab/simulink软件平台,搭建了包括风力机、永磁同步发电机、变流器等组件的并网型永磁同步风力发电机组的系统仿真模型,并根据矢量控制原理对机组及背靠背式变流器进行了控制策略的仿真研究.仿真结果表明,所采用的结合最大风能捕获的矢量控制策略实现了风电机组的变速运行、最大风能利用和有功、无功的解耦控制;验证了所建立的永磁同步风力发电机组模型以及采用的控制策略的有效、可行性,对于实践具有重要的指导意义.     

A power conversion system for PMSG-based WECS operating with fully-controlled current-source converters

We propose a new power conversion system for a permanent magnet synchronous generator （PMSG） based grid-connected wind energy conversion system （WECS） operating with fully-controlled back-to-back current-source converters. On the generator side, two independent current-source rectifiers （CSRs） with space-vector pulse width modulation （SVPWM） are employed to regulate and stabilize DC-link currents. Between DC-link and the electrical grid, a direct-type three-phase five-level current-source inverter （CSI） is inserted as a buffer to regulate real and reactive power fed to the grid and thus adjusts the grid side power-factor. We also present a current-based maximum power point tracking （MPPT） scheme, which helps the generator extract the maximum power through closed-loop regulation of the generator speed. By applying the multilevel modulation and control strategies to the grid-side five-level CSI, a multilevel output current waveform with less distortion is produced, and the bulk requirement of the output capacitor filter to eliminate the harmonic current is reduced. All the proposed concepts are verified by simulation models built in a PSIM environment.