A robust complex-domain state estimator using synchrophasor measurements

Phasor measurement units (PMUs) have been widely deployed in modern power grids, which provides a great opportunity for high-precision and real-time power system state estimation. If power networks are completely observable by PMUs, linear state estimation can be achieved with massive synchronous data. In this paper, the analysis of phasor error is presented and a complex number weighted least squares (CWLS) algorithm for state estimation is proposed, which shows high computational efficiency and stronger robustness to phasor errors. Meanwhile, self-adaptive weight and bad data identification techniques are developed to enhance the CWLS's performance. Test results on various IEEE test systems and the realistic power grid validate the effectiveness and superiority of the proposed CWLS algorithm, outperforming the conventional weighted least squares (WLS) state estimation method as well as other existing industrial-grade approaches.