Comparison of harmonic propagation methods considering uncertainties of harmonic injection

Probabilistic harmonic power flow (PHPF) is the basis of evaluating the impact of new energy integration to the grid. A PHPF scheme based on 2m+1 point estimate method (2m+1 PEM) was proposed in this paper on account that the uncertainties of injected harmonic current amplitudes and phases caused by intermittent and volatile new energy power generation device connected to the electricity grid. This method avoids the establishment analytic form relationship between input random variables and output random variables. According to the high order moment of sample data to makeup estimation point, the expectation, variance and other statistical information of branches could be calculated. Actual example is adopted to validate the method described in this article and result show that the accuracy of this method is similar to the ratio of the Monte Carlo simulation method in the case of less calculated amounts. As a comparison of interval analysis method (IAM), the results are more scientific and reasonable. Moreover, considering double uncertainties including amplitude and phase of harmonic injection source matches the practice better.