基于能量谱分析的被动式孤岛检测方法

提出了一种新的基于信号能量谱分析ESA(energy spectrum analysis)的孤岛检测方法,并对所提出的检测特征量在孤岛发生前后的变化进行了深入分析,对ESA方法的孤岛检测有效性及抗扰动性进行了仿真及实验验证。实验结果表明,ESA方法在分布式发电单元与本地并联谐振负载间存在功率匹配,传统过/欠电压、过/欠频率方法落入盲区内时仍可有效识别孤岛,检测需时远小于IEEE 1547-2003标准所规定的时间,且不易受系统暂态过程影响;同时,由于没有向系统中加入扰动信号,不会对电能质量产生影响。

Passive Islanding Detection Based on Signal Energy Spectrum Analysis

A novel islanding detecting method based on energy spectrum analysis(ESA) was proposed, and the ch-ange of the proposed detection feature during the islanding occurrence was analyzed, simulation and experimental results were provided to verify the validity and robustness of ESA method. The results show that, the proposed EAS method is able to detect islanding within the required time specified by IEEE 1547-2003 standard while there is power balance between the distributed generator and the local load before and after islanding occurs, and he traditional methods of under/over voltage and under/over frequency fall in none detection zone and is not susceptible to system transient process. In addition, ESA method has no negative impact on power quality for injecting no disturbance into the electric power system.