Correction of Time-varying PMU Phase Angle Deviation with Unknown Transmission Line Parameters

卷:9

Article

关键词: STATE ESTIMATION;    ONLINE CALIBRATION;    IDENTIFICATION;    ERRORS;   

DOI  :  10.17775/CSEEJPES.2021.07280

来源: SCIE

【 摘 要 】

Phasor measurement units (PMUs) provide useful data for real-time monitoring of the smart grid. However, there may be time-varying deviation in phase angle differences (PADs) between both ends of the transmission line (TL), which may deteriorate application performance based on PMUs. To address that, this paper proposes two robust methods of correcting time-varying PAD deviation with unknown parameters of TL (ParTL). First, the phenomena of time-varying PAD deviation observed from field PMU data are presented. Two general formulations for PAD estimation are then established. To simplify the formulations, estimation of PADs is converted into the optimal problem with a single ParTL as the variable, yielding a linear estimation of PADs. The latter is used by second-order Taylor series expansion to estimate PADs accurately. To reduce the impact of possible abnormal amplitude data in field data, the IGG (Institute of Geodesy & Geophysics, Chinese Academy of Sciences) weighting function is adopted. Results using both simulated and field data verify the effectiveness and robustness of the proposed methods.