Abstract: Measurement error is the deviation of the measured value from the true value. As the true value is not available in practice,the traditional state estimation model based on measurement error theory has great limitations. Firstly,the optimal buffer length of the PMU is determined and unified with the SCADA data to the same time fraction based on the Mahalanobis distance. Secondly,in the framework of two-stage algorithm,based on the uncertainty measure theory and the relative deviation of measurement points under this theory,considering the strict zero injection constraint relationship,and aiming at minimizing the sum of the relative deviation of weighted uncertainty measures,a power system state estimation method based on improved two-stage robust optimization is proposed. The simulation results show that,compared with the traditional state estimation method,the proposed method can strictly satisfy the zero injection power of the zero injection node,and has good robustness and high consistency of the estimation results.