Partial discharge direction‐of‐arrival estimation in air‐insulated substation by UHF wireless array and RSSI maximum likelihood estimator. Issue 23 (21st October 2020) - Han, Bei
Abstract : The quick detection and localisation of partial discharge (PD) in an air‐insulated substation (AIS) based on ultrahigh‐frequency (UHF) sensor arrays are efficient for power equipment monitoring. The adopted UHF PD time difference‐of‐arrival (DOA) methods mainly use the time difference of electromagnetic wave signals. Thus, the system requires both a high‐sampling rate and time synchronisation accuracy, leading to a high cost and large size. In this study, the feasibility and accuracy of PD DOA in an AIS were investigated using an UHF wireless sensor array and the received signal strength indicator. First, the power pattern of the designed UHF wireless sensor array was obtained via an offline experiment. Then, a statistical approach to the PD DOA method based on the maximum likelihood estimator was employed to obtain the preliminary DOA result. Finally, interpolation and clustering algorithms were used to improve the accuracy of the DOA. A laboratory test was conducted. The average error of the PD DOA was <6°, and the cost‐effectiveness and portability were clearly improved.