Robust adaptive Unscented Kalman Filter with gross error detection and identification for power system forecasting-aided state estimation

Abstract

Owing to the effect of measurement noise and sudden changes in the power system, the robustness of state estimation for power system becomes very important. The Unscented Kalman Filter (UKF) is widely used for state estimation. However, it does not consider the influence of different kinds of gross errors. To better deal with gross errors, a robust adaptive UKF with gross error detection and identification (RAUKF-GEDI) is proposed, which uses the robust generalized correntropy loss in the UKF framework. The RAUKF-GEDI detects gross errors by hypothesis testing, and then uses the moving window to identify and classify three kinds of gross errors. Subsequently, the RAUKF-GEDI estimates the magnitudes of the gross errors to further compensate the measurements, and finally uses the compensated measurements to re-estimate the state to obtain precise estimated states. In addition, RAUKF-GEDI also introduces adaptive covariance matching method for state estimation. The RAUKF-GEDI is applied to the state estimation for power systems where the measurements are contaminated by three kinds of gross errors. Finally, the RAUKF-GEDI is also applied to the practical power system of Zhejiang Juchuang Smart Technology Company Park. The results show that the RAUKF-GEDI can detect and identify gross errors and enhance the robustness of UKF.