基于阻抗约束的谐波溯源方法

Harmonic Traceability Method Based on Impedance Constraints

提出一种基于阻抗约束的公共连接点(PCC)主谐波源溯源方法。根据系统侧阻抗和用户侧阻抗固有特征,结合PCC处谐波电压电流测量信息,采用相量投影法判断系统侧的主谐波源,利用严格不等式制约判断用户侧的主谐波源。对于两侧阻抗性质不同的更复杂情况,采用几何学余弦定理和严格不等式追溯主谐波源,并从谐波源幅值大小和矢量关系加以验证。利用置信区间去除异常测量数据,对多场景实测数据进行谐波溯源分析,结果表明了文中方法的有效性。

Based on the impedance constraints, a new method is proposed to trace the main harmonic source at the point of common coupling（ PCC）. According to the inherent features of utility and customer impedances and combining with the recorded harmonic voltages and currents at PCC, the vector projection technique is used for judging the main harmonic source of the utility side. Also, the strict inequality constraints are applied to determine the main harmonic source of the customer side. Besides, as for the more complex conditions where the properties of the utility and customer impedances are different, the main harmonic source is traced by the cosine law of geometry and strict inequality. Based on the magnitude and phasor relations of harmonic sources on the two sides, the impedance constraints are worked out. Furthermore, the confidence interval is employed to remove the abnormal monitoring data. The harmonic traceability calculation of multi-scene measured data demonstrates the validity of the proposed method.