孤岛保护灵敏性和稳定性的仿真模拟与检测

摘要

针对光伏并网系统经常出现的孤岛效应现象,本文提出一种对孤岛效应进行仿真的模型,并通过模型对保护系统灵敏性和稳定性进行检测;本文基于 MATLAB/SIMULINK,建立电力系统仿真模型,并通过断路器控制孤岛现象的产生与消除;通过设置负载与分布式电站的不平衡情况,检测被动式孤岛保护的灵敏性;在仿真系统设置不同位置,不同类型的故障点,检测被动式孤岛保护的稳定性.最后对仿真系统的结果分析表明:无法同时增强系统灵敏性和稳定性,只能根据电力系统需求合理优化保护系统;选择合理的保护阈值,和持续时间.此模型能够合理仿真电力系统,并对孤岛保护灵敏性和稳定性进行检测,对未来光伏并网保护系统的发展和应用有重要意义.%Directing at the islanding phenomenon which often appears in photovoltaic(PV)grid-connec-tion system,this paper proposes an islanding effect simulation model,through which sensitivity and stability of this protection system is detected;Using MATLAB/SIMULINKE,power system simulation model is established;a circuit breaker can control the occurring and clearing of islan-ding phenomenon;Through setting imbalance between load and distributed power generation,sen-sitivity of the passive islanding protection is detected;The different kinds of faults with different locations are sett to detect stability of the passive islanding protection;The results show that the system can not enhance the sensitivity and stability at the same time.It can only optimize the pro-tection system according to power system demands,and select reasonable protection thresholds and time duration.This model can simulate the power system reasonably,detect the sensitivity and stability of the islanding protection,which is of great significance to the development and applica-tion of the future PV grid-connection protection system.