With the wide adoption of phasor measurement unit(PMU)in energy management systems

research on dynamic state estimator for synchronous machine based on PMU is attracting more and more attention. Should there exist bad data

the effect of filtering would be seriously affected. First

an algorithm for dynamic state estimation based on unscented Kalman filter is described. But as the PMU data is of poor quality

to solve problem

the time-varying residual threshold is found by deriving the residual equation. Then

the position of bad data measuring point is determined by an iterative detection method. The corresponding measurement of the bad data is ruled out and repeated for correction of the estimation. Simulation results show that the proposed algorithm can effectively restrain the influence of bad data on state estimation.