基于复合判据的谐波/间谐波源识别方法

Identification of harmonic and interharmonic sources based on composite criterion

提出一种基于多种判据进行组合判别的谐波/间谐波源识别方法。在对有功功率符号进行分析的同时将无功功率与有功功率之比作为参考,判断功率角测量的可信性。在此基础上,根据负荷阻抗通常远大于系统阻抗的事实,追加绝对阻抗对不可信的数据进行补充判断,并利用有功功率大小关系判断是否有背景谐波/间谐波源共同存在的复杂情况。提出一种时域测量法提取谐波和间谐波参数,保证可获取更多的数据样本。对于间谐波源,利用间谐波成对存在的特点增加了补充判据。仿真实例证明,将各种方法结合在一起进行复合判断,能增强谐波/间谐波源识别的稳健性。

A method to identify harmonic and interharmonic sources is proposed based on composite criterion,which analyzes the sign of active power and takes the ratio of reactive power and active power as a reference to judge the credibility of power angle measurement. Furthermore,it also takes the absolute impedance ,which is normally far larger than the system impedance,as an additional criterion to identify the unreliable data and determines the co-existence of background harmonic sources and inter-harmonic sources according to the amount of active power. A time,domain measuring method is proposed to extract the harmonic and interharmonic parameters for getting more data samples. As the interharmonic appears in pairs,a supplementary criterion is added. Simulation proves that,the combination of different identification methods increases the identification robustness.