Grey series time-delay predicting model in state estimation for power distribution networks

摘要

A new combined model is proposed to obtain predictive data value applied in state estimation for radial power distribution networks. The time-delay part of the model is calculated by a recursive least squares algorithm of system identification, which can gradually forget past information. The grey series part of the model uses an equal-dimension-new-information model (EDNIM) and it applies 3-points-smoothing method to preprocess the original data and modify remnant difference by GM (1, 1). Through the optimization of the coefficient of the model, we are able to minimize the error variance of predictive data. A case study shows that the proposed method achieved high calculation precision and speed and it can be used to obtain the predictive value in real-time state estimation of power distribution networks.