Distribution network parameter estimation method based on interval harmonic state estimation and prediction-correction

When it comes to the problem of unknown line parameters, state estimation is one of the effective methods to identify the line parameters, but state estimation requires that the whole network can be observed. Aiming at the problem that phasor measurement unit (PMU) configuration cost and technical limitations cannot meet the observability of the whole network, this paper uses the data of power quality monitoring device (PQMD) as a supplement to the PMU measurement data. In this paper, a method for estimating the parameters of distribution network lines based on interval harmonic state estimation and predictive correction is proposed. The measured data and line parameters are described as affine interval variable to be solved alternately, which are less conservative and have higher parameter accuracy than traditional interval algorithms.