| 引用本文: | 戴明,贾科,方煜,杨哲,毕天姝,张弛.独立运行微电网的故障特性分析及其线路保护研究[J].电力自动化设备,2019,39(4): |
| DAI Ming,JIA Ke,FANG Yu,YANG Zhe,BI Tianshu,ZHANG Chi.Fault characteristic analysis and line protection research of independent microgrid[J].Electric Power Automation Equipment,2019,39(4): |
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| 摘要: |
| 针对变流器接口电源区别于传统电源的故障特性和其分散接入微电网的拓扑结构使传统配电网保护难以快速可靠动作的问题，推导独立运行微电网不同类型电源支路的等效正序故障分量阻抗解析表达式，分析采用不同控制策略时，在故障前负荷情况、故障后输出电流幅值及外部等值阻抗影响下等效正序故障分量阻抗角的变化规律，并对微电网中不同位置正序故障分量方向元件的动作性能差异进行论证。进而提出一种基于线路正序电流故障分量与分布式光伏电源故障前电流相位比较的故障方向判断方法，并利用光伏支路电流突变量和光伏功率参考值突变量构造启动逻辑，形成闭锁式保护动作方案，可以以最小范围快速切除不同类型故障线路。PSCAD/EMTDC仿真结果验证了所提方案的正确性。 |
| 关键词: 微电网 继电保护 等效正序故障分量阻抗 故障分量方向元件 |
| DOI：10.16081/j.issn.1006-6047.2019.04.020 |
| 分类号:TM761 |
| 基金项目:国家重点研发计划项目(2016YFB0900203)；国家自然科学基金资助项目(51407067)；中央高校基本科研业务费专项资金资助项目(2016ZZD01);“111”计划项目(B08013) |
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| Fault characteristic analysis and line protection research of independent microgrid |
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DAI Ming1, JIA Ke1, FANG Yu1, YANG Zhe1, BI Tianshu1, ZHANG Chi2
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1.State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China;2.Electric Power Research Institute of Guangdong Power Grid Co.,Ltd.,Guangzhou 510080, China
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| Abstract: |
| Since differences of fault characteristic between converter-interfaced source and traditional generator and topology of distributed access of converter-interfaced source, it is difficult for traditional distribution network protection to act quickly and reliably. The analytical expressions of equivalent positive-sequence fault component impedance of different power source branches in independent microgrid are deduced, the variation rules of impedance angle of equivalent positive sequence fault component under influences of load conditions before fault, output current amplitude after fault and external equivalent impedance with different control strategies are analyzed, and the action performance difference of positive-sequence fault directional elements at different locations in microgrid is analyzed. On this basis, a fault direction judgment method is proposed based on phase comparison between positive-sequence fault component current and the distributed PV(PhotoVoltaic) current before fault. The start-up logic is constructed by using increments of PV branch current and PV power reference value to form a locking-type protection scheme, which is able to remove lines of all types of fault in a minimum range. The correctness of the proposed scheme is verified by results of PSCAD/EMTDC simulation. |
| Key words: microgrid relay protection equivalent positive-sequence fault component impedance fault component based directional relay |
