Fault Tolerant Extended Kalman Filter for Power Grid Synchronization Estimation Against Partial Missing Measurements

Aiming at the problem of partial measurement loss of power grid synchronous estimation, a resilient fault-tolerant extended Kalman filter (RFTEKF) is proposed to dynamically track voltage amplitude, voltage phase angle and frequency. First, the positive sequence fast estimation model of three-phase unbalanced network is established. Secondly, the loss phenomenon of measurements occurs in a random way and the randomness of data loss is defined by the discrete distribution of the interval [0,1]. Subsequently, a resilient fault- tolerant extended Kalman filter based on the real-time estimation framework is designed by using time-stamp technique to acquire partial data loss information. Finally, extensive simulation results manifest that the proposed RFTEKF can synchronize the power grid significantly more effectively than the traditional extended Kalman filter (EKF).

I. Introduction

In recent years, great changes have taken place in the power grid [1]. On the one hand, there has been an increase in the rate of renewable energy generation integration.; on the other hand, intelligent load control, energy storages and new energy vehicles are also widely deployed [2]. It is not hard to predict that the deployment of distributed generation systems (DPGS) will increase at a high rate of speed due to the need to produce more clean energy [3]. As a key factor in the accurate control of grid-connected converters and DPGS, the grid synchronization with high accuracy is necessary and vital. Without precise grid synchronization, the network of our utility many face the issue of instability or even black-out [4]•