直流与交流复合电压下的局部放电研究

Research on Partial Discharge Under DC and AC Composite Voltage

以±500 kV直流输电系统为研究背景,通过搭建的交直流复合电压实验平台,针对空气中的“针-板电极”模型,进行了局部放电实验。对比分析在交直流复合电压以及交流或直流电压下,单个放电脉冲的时域和频域特性,以及局部放电脉冲序列相对试验电压交流分量的相位分布特性。希望通过本组实验研究,让运维人员对直流系统中复合场强下设备绝缘问题有新的思考角度。

This research was based on±500kV HVDC system,the AC and DC composite voltage experimental platform was built to test the PD signals with a metal needle-plate model.The pulse wave shape and frequency spectrum were analyzed,and compared with PD signals under conventional AC or DC voltage,the phase-resolved distribution is analyzed to depict the new characteristics of PD under different AC component.This study would share a new view with the maintenance of converter transformer,of which the valve side bushing are stressed by AC/DC composite voltage.