IIDG接入对配电网保护的影响分析  

Analysis of impact of IIDG access on distribution network protection

作　　者：周石金 何晋[1] 杨凡 骆通 管恩齐 ZHOU Shijin;HE Jin;YANG Fan;LUO Tong;GUAN Enqi(School of Electrical and Information Engineering,Yunnan Minzu University,Kunming 650000,China)

机构地区：[1]云南民族大学电气信息工程学院,云南昆明650000

出　　处：《现代电子技术》2021年第17期151-156,共6页Modern Electronics Technique

基　　金：国家自然科学基金资助项目(61365007);国家自然科学基金资助项目(61761049);云南省教育厅科学研究基金项目(2020Y0242)。

摘　　要：由于接入逆变型分布式电源的配电网与传统配电网有很大区别,同时其故障特性受控制策略的影响,使得传统配电网的保护可能会拒动或者误动,特别是在高渗透率下,需要分析计及控制策略的IIDG接入对保护的影响,从而为引入安全、可靠的保护方案提供基础。针对并网运行时常采用的PQ控制IIDG,首先分析对三段式电流保护的影响,主要考虑IIDG在母线处接入且不同区域发生故障时的情况;然后分析电网运行在不同潮流方向时,IIDG接入对配电网方向性电流保护的影响;再分析IIDG在母线以及线路处接入时,对距离保护的影响。通过分析可知,IIDG的接入可能会引起三段式电流保护的拒动或者误动,方向性电流保护不能正常切除故障线路和距离保护Ⅱ段失去作用。最后在PSCAD/EMTDC仿真软件中进行了算例验证。Since the distribution network connected to the inverter-interfaced distributed generator(IIDG)is very different from the traditional distribution network and its fault characteristics are affected by the control strategy,the protection of the traditional distribution network may be rejected or operated mistakenly,especially under high penetration rate. Therefore,it is necessary to analyze the impact of IIDG access taking into account the control strategy on the protection,so as to provide a basis for the introduction of safe and reliable protection schemes. For the PQ controlled IIDG that is often used in grid-connected operation,the impact on the three-stage current protection is analyzed,mainly considering the situation when IIDG is connected at the bus and faults occur in different areas. And then,the impact of IIDG access on the directional current protection of the distribution network is analyzed when the grid runs in different power flow directions. Moreover,the impact of IIDG on the distance protection is analyzed when it is connected at the bus and the line. It can be known from analysis that the access of IIDG may cause the refusal or mis-operation of the three-stage current protection,the directional current protection cannot normally cut off the faulty line,and the distance protection Ⅱ section fails. Finally,it is verified by the simulation software PSCAD/EMTDC.

关 键 词：IIDG 配电网 故障特性 保护方案 PQ控制 三段式电流保护 方向性电流保护 距离保护 PSCAD 

分 类 号：TN99-34[电子电信—信号与信息处理] TM713[电子电信—信息与通信工程]