深度故障下双馈风电机组无Crowbar保护的可控LVRT技术研究

项目名称： 深度故障下双馈风电机组无Crowbar保护的可控LVRT技术研究

项目编号： No.51477064

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 电工技术

项目作者： 邹旭东

作者单位： 华中科技大学

项目金额： 88万元

中文摘要： 目前，商用DFIG普遍采用带Crowbar保护的LVRT方案，但其固有不可控特性将难以适应未来更高技术标准的并网规范。本项目拟开展电网深度故障下无Crowbar保护的DFIG励磁控制LVRT方案的机理及其实现技术研究，主要涉及有限变流器容量下不脱网可控运行的LVRT物理极限、贯穿整个故障期间的励磁控制目标自动优化算法及控制技术两大方面。具体内容包括：构建包括输变电网络和转子侧工况在内的DFIG机组暂态特性分析模型；研究DFIG电磁暂态时间尺度与并网规范中动态无功支撑响应时间的矛盾及解决方案；有限变流器电压电流容量约束下的DFIG励磁控制LVRT物理极限及其对应控制策略；考虑变流器容量约束和外端口性能要求的控制指令动态优化方案。相比现有的LVRT方案，研究成果可提供一套经济性、技术性能更优的替代方案，特别是响应并网规范中的快速动态无功支撑要求，并为DFIG的可控LVRT技术标准提供理论参考。

中文关键词： 低电压穿越；双馈风电机组；无撬棒保护；深度故障

英文摘要： So far, the commercial DFIGs mainly adopt crowbar to meet the LVRT requirement, however, uncontrollable as crowbar's inherent characteristic make it more and more difficult to achieve higher grid-connected standards in the future. The mechanism and realization technology of the crowbarless LVRT control strategy for DFIG under severe grid faults will be systematically studied. It includes two major contents: one is the physical limits of controllable LVRT under limited converter rating and the other is the control objective optimization scheme and its realization technology throughout the grid faults. The research would be done as following: firstly, modeling the generalized transient DFIG within transmission networks and rotor side conditions; secondly, analyze the DFIG electromagnetic transient time-scale and its response to the code requirements on dynamic reactive support response time; thirdly, the physical controllable LVRT limits and corresponding control strategy of DFIG with specific converter current-voltage rating; fourthly, the optimized control objective throughout the whole grid faults. Compared with the current mainstream crowbar LVRT scheme, this research will come out to bring us a substitute solution with better economic and technical characteristics, especially in fast reactive power support, and will provide a theoretic reference to controllable LVRT standard at the same time.

英文关键词： LVRT;DFIG;Crowbarless protection;severe grid faults