文章摘要
杨启帆,刘益青,朱一鸣,等.适用于DFIG并网线路的改进负序方向元件[J].电力系统自动化,2019,43(10):118-126. DOI: 10.7500/AEPS20180816001.
YANG Qifan,LIU Yiqing,ZHU Yiming, et al.Improved Negative Sequence Directional Element for Transmission Line Connecting DFIG[J].Automation of Electric Power Systems,2019,43(10):118-126. DOI: 10.7500/AEPS20180816001.
适用于DFIG并网线路的改进负序方向元件
Improved Negative Sequence Directional Element for Transmission Line Connecting DFIG
DOI:10.7500/AEPS20180816001
关键词: 风力发电  双馈感应发电机  负序方向元件  转子侧变换器控制  撬棒
KeyWords: wind power generation  doubly-fed induction generator  negative sequence directional element  rotor-side converter control  crowbar
上网日期:2019-04-26
基金项目:山东省自然科学基金资助项目(ZR2018MEE039)
作者单位E-mail
杨启帆 济南大学自动化与电气工程学院, 山东省济南市 250022  
刘益青 济南大学自动化与电气工程学院, 山东省济南市 250022 cse_liuyq@ujn.edu.cn 
朱一鸣 济南大学自动化与电气工程学院, 山东省济南市 250022  
陈国斌 济南大学自动化与电气工程学院, 山东省济南市 250022  
摘要:
      负序方向元件广泛应用于输电线路的纵联保护。随着风力发电快速发展,双馈感应发电机(DFIG)大规模接入电网使得电源的负序等值阻抗不再固定,传统负序方向元件不再适用。通过推导转子侧变流器不间断控制和撬棒投入两种工况下DFIG的负序等值阻抗解析表达式,得到两种工况下的负序等值阻抗相角的变化规律。发现传统负序方向元件受DFIG接入的影响,存在灵敏度下降甚至不正确动作的问题。为此,提出了一种负序方向元件的改进措施:故障前,利用DFIG参数在线确定不同工况下的最大灵敏角;故障后,根据DFIG运行状态,采用灵敏度和可靠性较高的动作判据。数字仿真结果验证了改进后的负序方向元件具有灵敏度高、自适应DFIG运行状态等优点。
Abstract:
      Negative sequence directional element is widely used in the pilot protection of transmission lines. With the rapid development of wind power generation, a large scale of doubly-fed induction generator(DFIG)is connected to the grid and the negative sequence equivalent impedance of power source is no longer fixed, which destroys the theoretical basis of the traditional negative sequence directional element. This paper derives the analytic expressions of the negative sequence equivalent impedance of DFIG under two situations, which are the uninterrupted control by the rotor-side converter and the crowbar resistance being thrown into, respectively. Subsequently the change rules of phase angles of negative sequence equivalent impedance have been obtained under two situations. It has been found that the traditional negative sequence directional element faces the problems of sensitivity and reliability due to the influences of DFIG. Therefore, an improvement measure of the negative sequence directional element has been proposed as follows: before faults, the maximum sensitivity angle under different operation states is determined by DFIG parameters in the mode on line; after faults, the action criterion with higher sensitivity and reliability is adopted according to DFIG operation states. Digital simulation results show that the improved negative sequence directional element has higher sensitivity and can be well adapted to various operation states of DFIG.
查看全文(Free!)   查看附录  查看附录   查看/发表评论  下载PDF阅读器