The Study Of High Voltage Bushing Insulation Based On Dielectric Response

Bushing which is a key component of electrical equipment, will bear a greater load and electric stress. The stability of the entire power grid operation will be decided by safe and reliable high voltage bushing. Especially in UHV transmission system, the level of pressure is higher, the operating environment is more complex. A higher requirement of insulation test for bushing is required. Currently it is lack of specific methods for high voltage bushing insulation state. There are certain problems in terms of the reliability and availability of conventional insulation testing. Therefore, the study of high-voltage bushing insulation state detection method has important academic value and engineering applications.In this paper, the dielectric response of high voltage bushing is studied by high voltage and insulation theory. The extended Debye equivalent model of high-voltage bushing paper insulation is built. The simulation analysis of PDC and RVM of bushing is completed. The law of dielectric response and external factors is explored, which will provide theoretical guidance for High voltage bushing insulation aging research. Design and manufacture of bushing sample, carry out a series of experiments. The relationship between dielectric response and external factors such as temperature, voltage, time and water content is obtained.By a large number of experiments get the following rules:Temperatures will increase the amplitude of the voltage and current. The voltage and current curves of time domain dielectric response will increase due to the intensity of the degree of aging. Dominant time constant and moisture content presents a good second-order function. When the aging situation of bushing is uneven, the RVM polarization spectrum will show a bimodal.The actual law is consistent with the simulation conclusion, which concluded that high voltage bushing aging state and its time-domain response curve relate much. Bushing aging state can be judged by six eigenvectors, which achieves the study of high voltage bushing insulation aging based on dielectric response. This method is a new breakthrough in the field of insulation testing of high voltage bushing, which has broad application prospects.