Contamination particles in the air are charged by the ion flow field around a DC corona discharge wire. The electric force acting on the charged particle is associated with the ion flow field and affects the particle deposition on insulators. In this study, the pollution characteristics of the porcelain insulators in an ion flow field were investigated by pollution experiments in a wind tunnel. The conductor wire was applied a higher DC voltage than the corona onset voltage and connected to a test insulator string. As the test parameters, the DC voltage was variable, the contamination particle diameter was set at 20 μm, and the wind speed was 2 m/s. The nonsoluble deposit density (NSDD) and its distribution on test insulators were measured, compared, and analyzed. The relationship was discussed between insulator pollution characteristics, the electric force on dust particles, and the ion flow field. The pollution characteristics revealed that the pollution on the upper part of the string increased with the test voltage and corona current. The non-uniformity of pollution along the string and on the upper/lower insulator surfaces also increased. However, the non-uniformity of pollution on the windward/leeward of the insulators decreased. The discussions indicated that the spatial ion flow field around the conductor affected dust motion when the dust was away from the insulator. The direction and magnitude of the electric force on the charged particles impacted the pollution distribution. The pollution level of the strings in the unenergized test was considerably lower than that in energized tests. The pollution level could be reduced by increasing the conductor corona under a specific corona current range.

空气中的污染颗粒被直流电晕放电线周围的离子流场带电。作用在带电粒子上的电力与离子流场有关，并影响粒子在绝缘体上的沉积。本研究通过风洞污染实验研究了离子流场中瓷绝缘子的污染特性。导线施加比电晕起始电压更高的直流电压并连接到测试绝缘子串。测试参数为直流电压可变，污染粒径为20 μm，风速为2 m/s。测量、比较和分析了不溶性沉积物密度 (NSDD) 及其在测试绝缘子上的分布。讨论了绝缘子污染特性之间的关系，灰尘颗粒上的电场力和离子流场。污染特性表明，串上部的污染随着测试电压和电晕电流的增加而增加。沿串和绝缘子上/下表面污染的不均匀性也增加了。但是，绝缘子上风/背风方向污染的不均匀性有所降低。讨论表明，当灰尘远离绝缘体时，导体周围的空间离子流场会影响灰尘的运动。带电粒子上的电场力的方向和大小影响了污染分布。未通电测试中串的污染水平明显低于通电测试中的污染水平。