State estimation considering uncertainty of measurement time deviation

To investigate the impact of uncertainty stemming from asynchronous measurement timings among various instruments on power system state estimation accuracy, the article employs the affine algorithm. This approach addresses the timing discrepancy between the state estimation moment and the actual measurement time. Firstly, the relevant historical measurement data are obtained through the historical load change curve, and the trend component of the measurement data is obtained by wavelet transform, so as to obtain the change rate of the measurement data. Then, the affine measurement at the time of state estimation is obtained by quantifying the change trend caused by the uncertainty of time deviation. Finally, utilizing the branch current as the state variable, the affine method is applied to obtain the estimation result. Through the IEEE33 node example, the affine estimation results under different time deviation ratios are compared, which verifies that th eproposed algorithm can track the time deviation changes of the measurement time and the state estimation time.