| 引用本文: | 孟龙,刘清贵,晁勤,等.基于LIBSVM识别并网PV系统阻抗的输电线电流保护自适应策略研究[J].电力系统保护与控制,2016,44(24):17-23.[点击复制] |
| MENG Long,LIU Qinggui,CHAO Qin,et al.Research on adaptive strategy for overcurrent protection based on identifying the equivalent impedance of grid-connected PV system by LIBSVM[J].Power System Protection and Control,2016,44(24):17-23[点击复制] |
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| 摘要: |
| 为解决并入配电网的光伏系统功率波动性导致输电线电流保护拒/误动问题，提出一种基于LIBSVM 的PV并网系统输电线电流保护自适应策略。基于Matlab/Simulink仿真平台搭建了结合低电压穿越控制策略模型的并网光伏系统动态仿真模型。在不同故障位置与故障类型情况下，针对正常运行时光伏功率的波动输出，仿真分析了光伏系统与低电压穿越控制策略协调下的故障特性及对配电网输电线电流保护产生的影响。在此基础上提出了一种基于支持向量机(SVM)识别PV并网系统不同输出功率时等效阻抗的方法，制定了输电线电流自适应保护判据，依据光伏系统输出功率和运行方式变化动态调整整定值。仿真验证表明:所提出的自适应保护策略避免了保护拒/误动，提高了保护装置性能。 |
| 关键词: 并网光伏 低电压穿越控制策略模型 故障特性 电流保护影响 自适应保护判据 |
| DOI：10.7667/PSPC20162403 |
| 投稿时间：2015-12-23修订日期：2016-03-20 |
| 基金项目:国家自然科学基金资助项目(51367017);科技部国家国际科技合作专项资助(2013DFG61520) |
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| Research on adaptive strategy for overcurrent protection based on identifying the equivalent impedance of grid-connected PV system by LIBSVM |
| MENG Long,LIU Qinggui,CHAO Qin,WANG Yibo,LI Yuqiang |
(School of Electrical Engineering, Xinjiang University, Urumqi 830047, China
;State Grid Zigong Power Supply Company, Zigong 643000, China) |
| Abstract: |
| To solve the problem refusal/incorrect tripping of overcurrent protection caused by power fluctuations of the distribution grid-connected photovoltaic (PV) system, this paper proposes an adaptive strategy based on the LIBSVM for overcurrent protection. The PV system dynamic model which combines with low voltage ride through (LVRT) control strategy is built on the platform of Matlab/Simulink. It also simulates and analyses the characteristics of the short-circuit and the influence on overcurrent protection with the different fault at different locations during the normal operation of PV power output fluctuations. A method is proposed to identify equivalent impedance of the grid-connected PV system during different output based on support vector machines (SVM), a line current adaptive protection criterion is developed, which dynamically adjusts the setting value under the PV system output power and operating modes. The simulation shows that the adaptive strategy can avoid the problem refusal/incorrect tripping of overcurrent protection and improve protection’s performance. This work is supported by National Natural Science Foundation of China (No. 51367017) and International S&T Cooperation Program of China (ISTCP) (No. 2013DFG61520). |
| Key words: grid-connected PV LVRT control strategy characteristics of the short-circuit influence on overcurrent protection adaptive protection criterion |
