基于无相位实测数据的系统侧谐波阻抗估计方法

Harmonic Impedance Estimation Method on System Side Based on Measurement Data Without Phase Angle

系统侧谐波阻抗的准确估计是合理划分谐波责任的前提,已有方法估计谐波阻抗需要公共连接点的谐波电压电流相量信息,但在实际工程应用中,一般电能质量监测仪(如Fluke 1760等)都只提供量测点的谐波电压电流幅值及相互间的相位差而非谐波电压电流相量值,导致已有方法失效。在随机独立矢量法的基础上,提出了一种在监测数据无相位情况下的系统侧谐波阻抗估计方法,该方法只需要公共连接点谐波电压电流幅值及相互间的相位差,而无需谐波电压电流的相位角信息即可估计出系统侧谐波阻抗值,为有效解决工程实测数据无相位难题提供了一条新途径。通过算例仿真分析和工程实测数据分析,证明了所提方法的正确性和有效性。

The premise of quantifying harmonic contributions is to estimate the harmonic impedance on system side. The existing methods of calculating harmonic impedance require the phasor information of harmonic voltage and current at the point of common coupling, but in practice, only the amplitude values of harmonic voltage, current and the phase angle difference between them could be provided by power quality monitors(i.e. Fluke 1760), which causes the existing methods invalid. Based on the random independent vector method, a system-side harmonic impedance estimation method based on monitoring data without phase angle is proposed. The proposed method employs the amplitude of harmonic voltage or current and the phase angle difference between them instead of the phasor angle information at the point of common coupling, which provides a new way to solve the problem of monitoring data without phase angle. The validity of the proposed method is verified by the simulation and field cases.