不同比例复合电压下油纸绝缘局部放电起始阶段放电特性

Discharge Characteristics of Oil-paper Insulation at Initial Stage of Partial Discharge Under AC-DC Combined Voltage with Different Proportion

文中对不同比例交直流复合电压下油纸绝缘局部放电起始放电特性的相关参数进行了实验研究。搭建了球板电极、柱板电极、针板电极局部放电模型模拟不同缺陷,利用恒压法进行了不同比例交直流复合电压下的油浸纸板局部放电实验,对局部放电的相关参数随复合电压比例的变化规律进行了测量并加以研究。研究结果表明,随着复合电压比例上升在球板电极、柱板电极、针板电极局部放电模型的起始放电阶段交流分量幅值下降,直流分量幅值增加,放电次数下降,球板和针板电极会改变相位分布使其集中于90°~135°范围内,同时向45°方向扩展。球板电极最大放电量较为稳定,针板电极最大放电量随比例上升而减小,柱板电极最大放电量变化趋势相反。

The relative parameters of initial discharge characteristics of partial discharge of oil-paper insulation un- der AC- DC combined voltage with different proportion are studied experimentally. Ball-plate electrode, column- plate electrode, and needle-plate electrode partial discharge models are constructed to simulate different defects. The constant voltage method is employed to conduct an experiment of partial discharge in oil paper under AC/DC combined voltage with different proportion, the variations of the relative parameters of partial discharge with the proportion of combined voltage are measured and analyzed. Results show that： 1）at the initial stages of partial discharge, the AC component amplitudes of the models of ball-plate electrode, column-plate electrode, and needle-plate elec- trode decrease, the DC component amplitudes increase, and the discharging numbers reduce with the rising voltage proportion; 2）the ball-plate and needle-plate electrodes change their phase distribution to focus in the range of 90°to 135°, extending to the direction of 45°; and 3）the maximum discharge of the ball-plate electrode is stable, the maximum discharge of the needle-plate electrode decreases with the umn-plate electrode increases with the proportion. proportion, while the maximum discharge of the col-