110kV覆沙复合绝缘子串沿面电位与电场变化规律研究

为了研究沙尘沉积对复合绝缘子串沿面电位与电场的影响，基于有限元法，建立了110 kV 工作电压下的复合绝缘子串的清洁与覆沙模型，分析了复合绝缘子表面在沉积沙尘不同的情况下， 其沿面电位与电场分布的变化规律。研究结果表明：复合绝缘子沿面电位与电场分布受绝缘子表面几何形状影响，当绝缘子沿面覆盖沙层时，对其沿面电位影响非常小，但是其沿面电场在覆沙处会下降，并且越靠近高低压两侧下降幅度越大，且下降幅度与沙层厚度无关。沙层中出现的无沙带会增大此处绝缘子沿面的电场强度，越靠近高低压两侧的绝缘子，增大幅度越大，且增大幅度与无沙带的宽度和沙层厚度都相关。

Study on the variation law of 110 kV sand-covered composite insulator string along surface potential and electric field

In order to study the influence of sand and dust deposition on the surface potential and electric field of the composite insulator string, based on the finite element method, the cleaning and sand covering model of the composite insulator string for 110 kV was established, and the changes of the surface potential and electric field distribution along the surface of the composite insulator were analyzed under the different conditions of sedimentary sand and dust. The results show that the composite insulator along the surface potential and elec- tric field distribution is affected by geometric shape of the insulator surface. When the insulator covers the sand layer along the surface, the impact on the potential along the surface is very small, but the electric field along the surface will fall at the sand cover, and the closer to both sides of high and low voltage, the greater the de- cline, and the decline is independent of the thickness of the sand layer. The sand-free belt in the sand layer will increase the electric field strength along the surface of the insulator here, and the closer to the insulator on both sides of the high and low voltage, the greater the increase, and the increase is related to the width of the sand-free belt and the thickness of the sand layer.