风电机组选型分析

介绍了双馈风电机组和直驱风电机组的工作原理和性能特点,并在此基础上对2种机组进行了定性分析和有关参数的定量比较,结合各自的实际运行情况,给出了风电场风电机组初步选型原则：双馈风电机组技术成熟．运行经验丰富,一段时期内可作为首选机型：技术经济条件允许时再结合具体情况考虑选用直驱尤其是永磁直驱风电机组,是未来风电场机型选择的新趋势。     

并网永磁直驱风电机组故障穿越能力仿真研究

随着电力电子器件成本下降,拥有全功率变换器的永磁直驱风机成为各国关注热点。风电场容量不断增大,要求风电机组具有故障穿越能力。本文以直驱同步风电发电机组为研究对象,利用matlab/simulink搭建了直驱同步风电机组的动态数学模型,对直驱同步风电机组故障穿越能力进行仿真研究,试验结果表明：在风电场接入点发生故障时,直驱同步风电机组具有故障穿越功能。尤其在电网发生电压跌落时,直驱风机能为系统提供一定的无功支撑。有效防止系统电压过多降落。提高了系统故障运行的稳定性。     

混合型风电机组技术与市场近况

集直驱永磁型和高速双馈型风电机组技术优势于一身,混合型风电机组近期受到更多关注。本文在描述该技术路线的同时,向读者简要介绍了混合型风电机组的技术特点及市场情况。     

一种新型的风电场机组配置方案

近年来建设的100MW风电场中,1.5MW以上的直驱风电机组与双馈风电机组是两大主力机型,其在风电场中的配置对并网后电网安全稳定运行有重要影响。本文根据直驱风电机组与双馈风电机组的各自特点以及不同的故障率,提出一种配置方案。     

基于正序阻抗的直驱风电机组次/超同步振荡影响因素分析

为深入研究直驱风电机组与交流电网的交互作用引发的次/超同步振荡问题,首先,利用谐波线性化方法建立直驱风电机组正序阻抗模型,并给出了次/超同步振荡的稳定性判据;其次,通过频率扫描法验证了模型的合理性;利用波特图,揭示电流环和锁相环控制参数对直驱风电机组次/超同步振荡特性的影响规律;最后,基于Matlab/Simulink仿真平台搭建直驱风电机组并网系统进行时域仿真,并与频域分析比较,验证了阻抗特性分析的合理性。     

直驱风电机组与SVG交互作用引发次/超同步振荡的机理与特性研究

为深入研究直驱风电机组与无功补偿装置交互作用引发的次/超同步振荡问题,首先,利用谐波线性化方法建立直驱风电机组与SVG交互作用的正序阻抗模型,并在此模型的基础上,给出了基于阻抗的稳定性判据;然后,通过波特图分析了SVG控制参数对直驱风电机组阻抗特性的影响,揭示锁相环和电流环控制参数对直驱风电机组与SVG交互作用的次/超同步振荡特性的作用规律;最后,基于Matlab/Simulink仿真平台搭建了直驱风电机组并网系统进行时域仿真,并与频域分析加以比较,验证了阻抗特性分析的合理性。     

基于PSCAD的永磁直驱风电机组简化模型研究

针对风电机组的电磁暂态模型求解耗时长、仿真计算工作量大、数值收敛性差等不足,在研究直驱机电暂态及运行控制方式的基础上,利用PSCAD仿真工具构建了直驱风电机组简化模型,并分别在恒定风速、阶跃风速和电网故障三种工况下进行了仿真验证。结果表明,基于PSCAD的直驱风电机组简化模型可行、有效,在保证一定的计算精度下,可大幅提高计算速度,且当风机台数增加时,速度提高更加明显。     

永磁直驱风电系统故障穿越技术研究综述

在分析永磁直驱风力发电系统拓扑结构的基础上,针对永磁直驱风电系统故障穿越时遇到的问题,从增加硬件电路和改进控制策略两方面对其实现电压故障穿越的方法进行了总结分析,然后对永磁风电机组的电压穿越技术的发展作了进一步的探讨。     

变速恒频直驱型风电系统低压穿越技术

随着变速恒频型风电在电网中所占份额不断增加,电力系统对并网风电系统的故障运行能力,尤其是电网电压瞬间跌落故障下的不间断运行能力提出了严格的要求,而基于全功率变流器的永磁直驱型风电系统已经被证实具有出色的低压运行特性.因此,本文对变速恒频直驱型风电系统低压穿越技术进行研究.首先分析了电网故障对直驱型风电系统的不良影响,然...     

含SVG直驱风电场降阶模型与宽频振荡抑制措施研究

在直驱风电机组状态空间模型、SVG状态空间模型的基础上,建立了含SVG直驱风电场并网系统降阶状态空间模型;分析发现直驱风电场内SVG可能引起宽频振荡.为了抑制含SVG直驱风电场内宽频振荡,提出了含SVG直驱风电场宽频振荡阻尼控制器设计方法.基于降阶状态空间模型,以目标振荡模式的阻尼比为目标函数,通过优化算法整定控制器参...     

全功率变流风力发电系统电压跌落响应特性研究

随着风电机组数量的增加,电网故障时风机的动态响应越来越重要。利用madab／simulink,在建立采用永磁同步电机的直接驱动型变速恒频风电系统模型的基础上,分析了电网电压分别跌落30％-10s、50％-0．58s,85％-0．2s时永磁直驱式风电系统的动态响应。并搭建了实验系统,进行了实验验证。结果表明,直驱式风电系统在3种典型跌落情况下,具有良好的低压度过能力。     

面向次同步振荡分析的直驱风电机群建模

针对低运行工况下直驱风电机群并网出现的次同步振荡(SSO)问题,基于图形化分块建模,在建立风力机、集电线路及电网等独立元件的模型基础上,构造不同集电线路拓扑结构下直驱风电机群的线性化模型.利用特征值分析法和阻抗分析法识别系统中存在的振荡模式,并分析运行工况、电流内环控制参数和风力机数量等因素对SSO频率和阻尼的影响.研...     

基于PSCAD/EMTDC的直驱式风力发电接入系统建模与仿真

针对频率可变的多极直驱式同步风力发电机接入系统,该文在考虑风力机大转动惯量的情况下,采用电网电压矢量定向和双闭环控制技术,实现了基于背靠背VSC换流器的有功无功独立控制。研究了不依赖于风速测量的直驱式机组最大功率追踪策略,桨距角控制器设计以及变风速下风电机组对电网的无功支持问题。最后通过PSCAD/EMTDC搭建了该接入系统模型,阶跃和随机风速下的仿真结果验证了该模型的合理性及控制策略的有效性。     

直驱式风力发电系统的应用分析

结合目前市场应用和实验研究情况，综合评述了直驱式风力发电系统。具体介绍了5种直驱式风力发电系统的特点、优劣及应用状况，直驱式风力发电系统中应用的电力电子变换器概况。通过综合比较，指出了直驱式风力发电系统的应用前景。     

Optimization of Multibrid Permanent-Magnet Wind Generator Systems

This paper investigates the cost-effective ranges of gearbox ratios and power ratings of multibrid permanent-magnet (PM) wind generator systems by using a design optimization method. First, the analytical model of a multibrid wind turbine concept consisting of a single-stage gearbox and a three-phase radial-flux PM synchronous generator with a back-to-back power converter is presented. The design optimization is adopted with a genetic algorithm for minimizing generator system cost. To demonstrate the effectiveness of the developed electromagnetic design model, the optimization results of a 500-kW direct-drive PM generator and a 1.5-MW multibrid PM generator with various gear ratios are, respectively, compared with those from other methods. Then, the optimal design approach is further employed for a range from 750 kW up to 10 MW. The optimization results of PM generator systems including direct-drive and multibrid wind turbine configurations are obtained, and the suitable ranges of gear ratios for different power ratings are investigated. Finally, the detailed comparisons of the most cost-effective multibrid PM generator system and the optimized direct-drive PM generator system are also presented and discussed. The comparative results have shown that the multibrid wind turbine concept appears more cost-effective than the direct-drive concept.      

基于转子动能控制的风电机组功率平滑控制结构及优化策略研究

采用转子动能控制方法对直驱永磁同步风力发电机组输出的有功功率进行功率平滑控制,并对控制效果进行优化。首先,分析转子动能控制造成功率损失的原因,并据此提出一种能够补偿功率损失的平滑指令,结合风电机组稳定性分析,得到风电机组采用功率平滑控制的条件,以此采用Matlab/Simulink进行仿真分析,验证所提控制策略的有效性。然后,利用模糊逻辑控制算法（FLC）进行优化控制,以提高风电机组输出有功功率平滑度和风能利用率,并改善由于功率指令切换造成的平滑度下降问题。最后,通过Matlab/Simulink进行仿真分析,对比不同参数下的优化效果,验证所提控制策略和优化方法的有效性。     

Multi-objective design optimization of a large-scale directdrive permanent magnet generator for wind energy conversion systems

This paper presents a simultaneous multiobjective optimization of a direct-drive permanent magnet synchronous generator and a three-blade horizontal-axis wind turbine for a large scale wind energy conversion system. Analytical models of the generator and the turbine are used along with the cost model for optimization. Three important characteristics of the system i.e., the total cost of the generator and blades, the annual energy output and the total mass of generator and blades are chosen as objective functions for a multi-objective optimization. Genetic algorithm (GA) is then employed to optimize the value of eight design parameters including seven generator parameters and a turbine parameter resulting in a set of Pareto optimal solutions. Four optimal solutions are then selected by applying some practical restrictions on the Pareto front. One of these optimal designs is chosen for finite element verification. A circuit-fed coupled time stepping finite element method is then performed to evaluate the no-load and the full load performance analysis of the system including the generator, a rectifier and a resistive load. The results obtained by the finite element analysis (FEA) verify the accuracy of the analytical model and the proposed method.     

Design optimization and site matching of direct-drive permanent magnet wind power generator systems

This paper investigates the possible site matching of the direct-drive wind turbine concepts based on the electromagnetic design optimization of permanent magnet (PM) generator systems. Firstly, the analytical models of a three-phase radial-flux PM generator with a back-to-back power converter are presented. The optimum design models of direct-drive PM wind generation system are developed with an improved genetic algorithm, and a 500-kW direct-drive PM generator for the minimal generator active material cost is compared to demonstrate the effectiveness of the design optimization. Forty-five PM generator systems, the combinations of five rated rotor speeds in the range of 10–30 rpm and nine power ratings from 100 kW to 10 MW, are optimally designed, respectively. The optimum results are compared graphically in terms of the generator design indexes. Next, according to the design principle of the maximum wind energy capture, the rotor diameter and the rated wind speed of a direct-drive wind turbine with the optimum PM generator are determined. The annual energy output (AEO) is also presented using the Weibull density function. Finally, the maximum AEO per cost (AEOPC) of the optimized wind generator systems is evaluated at eight potential sites with annual mean wind speeds in the range of 3–10 m/s, respectively. These results have shown the suitable designs for the optimum site matching of the investigated PM generator systems.