Study of charge accumulation on insulator surface in HVDC gas-insulated switchgear

Study of insulator surface charge accumulation and its suppression is one of the key technologies in developing HVDC gas-insulated switchgear. A new type of capacitive probe with good performance is developed for measuring insulator surface charge distribution, and effects of the polarity, amplitude, and time duration of the applied voltage on surface charge accumulation are studied. Experimental results show that the average charge density increases with the increase of the amplitude and time duration of the applied voltage, and surface charge distribution is closely related with the polarity of the applied voltage, moreover, methods of charge accumulation suppression are discussed.