通过理论分析,对孤岛保护建立了仿真模型.孤岛检测采用具有过/欠电压检测功能的电压相位突变检测方法,该检测方法克服了采用单一的电压相位突变检测方法在阻性负载下失效的问题,可以实现快速有效的孤岛检测功能,分析了孤岛检测盲区的负载参数范围,同时,提出了防止由于电网不稳定与大负载的突然投入或切除引起电网波动导致的虚假孤岛现象的误保护措施.本文通过理论分析、建模和仿真实验研究,验证了提出的孤岛保护模型的有效性和实用性.
A simulation model for islanding protection based on theoretical analysis was derived. Over/under voltage and phase jump detection methods were adopted in islanding detection. The method adopted can overcome the shortcoming that the phase jump detection method fails to work under resistive load, and it can achieve fast and effective islanding detection. The load parameters range of islanding nondetection zones was discussed. In particular, a novel measure was proposed to prevent fault islanding trips from grid instability or fluctuation which is caused by the sudden cut-in or removal of the load. In this paper, the model of islanding protection was built in detail. Theoretical analysis and simulation results showed that the proposed model is effective and practical.