三相电容式异步发电机的研究

分析了风力发电系统中异步发电机的应用情况,提出了一种新型的三相电容式异步发电机。该发电机克服了原有异步发电机功率因数过低的缺点,同时还可针对电机的不同运行点配置相应的电容,由此改善电机性能。这是普通异步发电机端部并联电容无功补偿所不能达到的。对两台样机进行试验对比,结果表明三相电容式异步发电机在风电系统中具有很高的应用推广价值。     

三相电容式异步发电机的研究

分析了风力发电系统中异步发电机的应用情况,提出了一种新型的三相电容式异步发电机。该发电机克服了原有异步发电机功率因数过低的缺点,同时还可针对电机的不同运行点配置相应的电容,由此改善电机性能。这是普通异步发电机端部并联电容无功补偿所不能达到的。对两台样机进行试验对比,结果表明三相电容式异步发电机在风电系统中具有很高的应用推广价值。     

变速恒频风力发电技术综述

阐述了常用的风力发电技术中的笼型异步发电机、永磁发电机、交流励磁双馈型发电机、无刷双馈发电机、磁场调制型发电机等5种变速恒频风力发电系统的原理及其应用;分析了各个系统的优缺点,并展望了发展趋势.     

三相电容式异步发电机在风力发电系统中的应用

分析了风力发电系统中异步发电机的应用情况,提出一种新型的三相电容式异步发电机,它克服了原有的异步发电机功率因数过低的缺点,同时也可使电机性能得到极大的改善.通过两台样机进行实验对比,实验数据表明三相电容式异步发电机在风电系统中有很高的应用推广价值.     

风力发电中的无功控制

在风力发电中，对于风力发电机吸收和产生无功功率的控制是一个重要的问题。文章介绍风力发电中无功控制的难题和在应用中出现的问题．以及传统的解决方法及其缺陷。还介绍一种新型的带有动态无功控制功能的风力机，详细列举了它的各种优点、在实际工程中的广泛应用和它广阔的前景。     

一种新型风力发电机的提出与实现

现有小型风力发电系统技术已相当成熟，但其所用的发电机存在一些缺点与不足。据此，提出一种新型的风力发电机，对其设计做论述。通过对样机的实验，证明方案的可行性。     

风力发电机及风力发电控制技术综述

介绍了各种类型风力发电机及其风力发电系统的特点,论述了风力发电机组的定桨距失速控制、变桨距控制及变速控制等控制方式,阐述了具有鲁棒性的非线性智能控制技术在风力发电中的应用研究.通过对比各种风力发电机和各种控制方法的优缺点,对未来风力发电机和风力发电控制技术的发展趋势做了展望.     

永磁直驱风电变流器无传感器控制研究

永磁直驱风力发电系统是一种新型的风力发电系统,具有广泛的应用前景。背靠背的全功率变流器是直驱型风力发电系统中的关键设备,既要实现对电网转换优质电能的功能,又要对永磁同步发电机(PMSG)进行控制。永磁同步发电机的无传感器控制技术具有重要的研究意义。根据永磁同步发电机的数学模型,利用其电磁、电气关系,提出了一种基于转子磁链闭环锁相环的永磁同步发电机位置的估算算法。通过仿真和实验结果表明,利用该估算方法能够准确计算出永磁同步发电机的位置,并可以利用其对永磁同步发电机实现有效的控制。     

风力发电系统中的异步发电机型及其并网技术

发电机是风力发电系统中重要的部件,因工作的特殊性在结构上及并网技术上与普通发电机略有不同。本文就风力发电系统中目前常见的几种异步发电机型及其并网技术作简单介绍。 1笼型异步感应发电机 笼型异步感应发电机结构、并网方法简单,价格低,适合在野外缺少维护的环境工作,因此在风电系统应用很广。     

兆瓦级风力发电机综述

阐述了风力发电机的组成及设计思想;介绍了新型兆瓦级风力发电机产品,如双馈异步、永磁和电励磁同步及直接驱动等发电机,为我国自主研制风力发电系统提供有价值的参考。     

软磁复合材料在轴向磁场永磁风力发电机中的应用

讨论了SMC在直驱风能转换系统中的轴向磁场永磁(AFPM)同步风力发电机设计中的应用。首先介绍了轴向磁场永磁电机的结构特点;然后介绍了SMC材料的特性,讨论了SMC材料在永磁风力发电机设计中的应用;最后使用有限元法将基于SMC的AFPM风力发电机与采用硅钢片定子铁心的AFPM风力发电机进行了比较,证明了所提方案是可行的。     

Speed control of grid-connected switched reluctance generator driven by variable speed wind turbine using adaptive neural network controller

In wind energy conversion system, variable speed operation is becoming popular nowadays, where conventional synchronous generators, permanent magnet synchronous generators, and doubly fed induction generators are commercially used as wind generators. Along with the existing and classical solutions of the aforementioned machines used in wind power applications, the switched reluctance generator (SRG) can also be considered as a wind generator due to its inherent characteristics such as simple construction, robustness, low manufacturing cost, etc. This paper presents a novel speed control of switched reluctance generator by using adaptive neural network (ANN) controller. The SRG is driven by variable speed wind turbine and it is connected to the grid through an asymmetric half bridge converter, DC-link, and DC-AC inverter system. Speed control is very important for variable speed operation of SRG to ensure maximum power delivery to the grid for any particular wind speed. Detailed modeling and control strategies of SRG as well as other individual components including wind turbine, converter, and inverter systems are presented. The effectiveness of the proposed system is verified with simulation results using the real wind speed data measured at Hokkaido Island, Japan. The dynamic simulation study is carried out using PSCAD/EMTDC.     

A unified approach for the solution of power flows in electric power systems including wind farms

This paper proposes a solution approach of the power flow problem to assess the steady-state condition of power systems with wind farms in a single frame of reference, in which the state variables of the wind generators are combined with the nodal voltage magnitudes and angles of the entire network for a unified iterative solution through the Newton-Raphson method. Different wind energy conversion systems (WECS) are mathematically derived from the steady-state representation of the induction generator. Suitable strategies for initializing the state variables of the wind generators are also proposed in this paper. Lastly, three numerical examples are presented to numerically illustrate the applicability of the proposed approach.     

Impact of FACTS controllers on the stability of power systems connected with doubly fed induction generators

The increasing power demand has led to the growth of new technologies that play an integral role in shaping the future energy market. Keeping in view of the environmental constraints, grid connected wind turbines are promising in increasing system reliability. This paper presents the impact of FACTS controllers on the stability of power systems connected with wind energy conversion systems. The wind generator model considered is a variable speed doubly fed induction generator model. The stability assessment is made first for a three phase short circuit without FACTS controllers in the power network and then with the FACTS controllers. The dynamic simulation results yield information on (i) the impact of faults on the performance of induction generators/wind turbines, (ii) transient rating of the FACTS controllers for enhancement of rotor speed stability of induction generators and angle stability of synchronous generators. EUROSTAG is used for executing the dynamic simulations.     

风电对电力系统运行的价值分析

从电力系统运行的角度，提出了基于随机模拟技术的定量分析计算风力发电对电力系统运行的价值的方法。定性地描述了风电并网引起的电力系统运行方式的变化和由此带来的发电变动情况。根据常规火电机组的边际发电成本曲线，分析了风电价值的构成。指出了风电价值与风电场所在地风资源特性、风电机组技术参数、风电负荷在电力系统负荷中所占比例以及配合风电运行的火电机组的耗量特性有关，给出院计算风电价值和灵敏度分析的数值实例。文中的概念性分析方法也适用于复杂电力系统。     

A comprehensive review on the grid integration of doubly fed induction generator

As a result of the growing demand for electricity and environmental constraints, the generation of electrical energy from renewable sources of energy has increased recently. The renewable energy sources, especially wind power plants are integrated to power networks all around the world. The rising share of wind turbine energy, in the existing power system, has created new opportunities and challenges. For wind turbine energy generation doubly fed induction generators are most suitable due to their various advantages over fixed speed wind turbine systems. These generators have ability to improve stability and power quality of the existing power systems. Therefore more attention has been paid by many researchers recently to address various challenges of grid connection of DFIG. A comprehensive survey, of different issues associated with integration of DFIG based system into the grid is presented in this paper.     

Analysis and investigation of size spectrum of synchronous machines operating as wind-power-generators in the range of rotation frequencies of 75–300 rpm

The modern design tendencies of wind power generators based on synchronous machines with permanent magnets have been analyzed. It is shown that it is possible to create a spectrum of wind power generators with tangential magnetic flux and stator concentric windings in the range of rotation frequencies of 75–300 rpm. Some parameters of the developed generators are presented.     

兆瓦级风力发电变流系统多重斩波器的研究

讨论了1.2MW变速恒频风力发电变流系统中的多重斩波器。变流系统采用AC/DC/AC结构,基于DSP控制,使得永磁同步电机输出的电能高效地传递到电网。其中多重斩波器采用平均电流法控制,利用状态空间平均法以及小信号模型分析了升压斩波电路,确定了电路的PI调节器参数。实验结果验证了理论分析,证明PI调节器具有很好的动态性能和稳态性能。     

改善接入系统同步稳定性的变速风电机组控制

为了改善风电接入系统的同步稳定性,采用基于能量守恒的方法构造含有风电机组的电力系统能量存储函数,以此为基础设计提高风电接入系统动态特性的双馈风力发电机控制策略,并分析了机组运行约束对控制效果的影响。控制方案利用变速风电机组特性,通过改变风机转速消除系统故障期间的不平衡能量,有效抑制系统同步机振荡。针对双馈感应型风场接入系统,在DIgSILENT/Power Factory中进行了仿真研究,仿真结果表明,不同系统运行方式下控制方案在有效改善风电接入系统同步稳定性的同时不会恶化系统电压稳定特性。     

A Review of Power Electronics for Wind Power

The paper reviews the power electronic applications for wind energy systems.Main wind turbine systems with different generators and power electronic converters are described.The electrical topologies of wind farms with power electronic conversion are discussed.Power electronic applications for improving the performance of wind turbines and wind farms in power systems have been illustrated.