沙尘环境下风速、粒径对直流金具起晕电压的影响

Influence of Wind Speed and Dust Particle Size on Corona Inception Voltage of DC Fittings

研究沙尘环境下风速、沙尘粒径对直流金具起晕电压的影响规律,对于指导极端气候条件下高压直流输电线路设计、运行、维护,增进系统的可靠性具有重要的意义,也是该领域的研究热点。选取4个不同直径的均压环为试品,在人工模拟沙尘气候环境下,利用紫外成像仪观测手段,分别测试了其在无风沙条件以及10-25 m/s风速、粒径〈65μm与〈105μm的典型沙尘这3种条件下的直流起晕电压,并通过电场模拟仿真对测试结果进行了分析。试验结果表明：沙尘介质环境会导致直流金具起晕电压出现下降;浓度一定的条件下,起晕电压随风速增加逐渐升高;相同风速下,粒径〈65μm的沙尘试样作用下金具起晕电压略低于粒径〈105μm的大粒径试样。

It is necessary to study the effects of wind speed and dust particle size on DC corona inception voltage of fittings so as to design and maintain HVDC transmission lines under extreme climate conditions. Therefore, four different-sized aluminum grading rings were taken as research objects. The corona inception voltage of each of these grading rings was tested under three experimental conditions： still air, 10-25 m/s wind speed with dust particles, and the diameter of particle is under 65 μm and 105 μm, respectively. The results were then verified by ANSYS simulation. It is indicated that the corona inception voltage will decreases under the influences of wind and dust particles. Moreover, the voltage under the same dust-particle concentration increases along with the wind speed raising. The voltage under 65-μm diameter dust particles is lower than that under 105-μm ones at each wind speed.