A novel method for estimating utility harmonic impedance based probabilistic evaluation

Abstract

Here, a novel method for estimating utility harmonic impedance (UHI) based on probabilistic evaluation is proposed. By analysing harmonic data, it is determined that UHI tends to obey a particular distribution, that varies with the amplitude of the background harmonics. Therefore, calculating the probability distribution of the UHI is considered to estimate its value. The UHI can be estimated by calculating the conditional probability density function of the background harmonics and prior distribution of UHI. The estimation results are not affected by the correlation of harmonic impedances between the two sides of the point of common coupling. The validity and accuracy of the proposed method were further verified through simulations and the analysis of field testing data.