基于暂态电流波形相关性的新能源场站送出线路纵联保护  

Transient Current Waveform Similarity Based Pilot Protection for Transmission Lines Connected to Renewable Energy Power Plants

作　　者：毕天姝[1] 李彦宾[1] 贾科[1] 杨奇逊[1] BI Tianshu;LI Yanbin;JIA Ke;YANG Qixun(State Key Laboratory of Altemate Electrical Power System with Renewable Energy Sources （North China Electric Power University）, Changping District, Beijing 102206, China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学)

出　　处：《中国电机工程学报》2018年第7期2012-2019,共8页Proceedings of the CSEE

基　　金：国家重点研发计划项目(2016YFB0900203);中央高校基本科研业务费专项资金(2016ZZD01);国家电网公司科技项目(5211JY16000U)~~

摘　　要：新能源电源通过变流器并网,其短路电流受控制策略影响而呈现幅值受限、频率为非工频、相角受控等特性,导致传统工频量保护动作性能下降、甚至出现误拒动。提出了一种适用于新能源场站送出线路的主保护原理,以保证新能源电力系统安全可靠运行。分析了同步发电机和各类新能源电源故障暂态电流波形特征,获知送出线路区内、外故障时两侧暂态电流波形相关性存在明显差异,进而提出了基于波形相关性的纵联保护新原理,利用相关系数度量波形相关性并构造了动作判据。仿真结果表明所提保护能够可靠、灵敏地识别送出线路区内、外各种类型短路故障,数据窗长仅为10ms,耐受过渡电阻和噪声的能力强,采用常规采样频率即可,容易推广应用。录波数据验证了所提保护有效性。With renewable energy generators （REGs） integrated into grid by the power converters, its fault current is featured with limited amplitude, non-power-frequency dominated and controlled phase angle, which leads to traditional relays based on power frequency facing low performance and even incorrect operations. In order to ensure a safe and reliable operation of the power system with PEGs, a novel primary protection was proposed for transmission lines connected to renewable energy power plants. Transient current waveforms provided by the synchronous generator and kinds of REGs were analyzed. The waveform similarity of double- ended transient currents was of obvious difference for the internal and external faults on the transmission line, and a waveform similarity based pilot protection was proposed. The correlation coefficient was adopted to calculate the similarity of transient currents and then the criterion was formed. Simulation results show that the proposed protection can identify all kinds of external and internal faults with good reliability and high sensitivity. Accompanied with common sampling frequency and a 10ms data window, the proposed protection is relatively robust to high level of noises and high fault resistance, which makes it feasible for industry application, Field data validates the effectiveness of the proposed protection.

关 键 词：暂态电流 波形相关性 纵联保护 送出线路 新能源场站 

分 类 号：TM743[电气工程—电力系统及自动化]