不同类型RTV憎水性及闪络特性分析

室温硫化硅橡胶（room temperature vulcanized silicone rubber，RTV）具有很好的防污性能，在电力系统中已广泛应用，但不同类型的RTV涂料防污性能不同。测定了不同RTV涂料的静态接触角，并对RTV涂料污闪后的憎水性恢复特性以及交直流下的闪络特性进行了试验分析。试验结果表明，长效型RTV涂料（P-RTV）的憎水性大于高自洁型RTV涂料（S-RTV）；在同一污秽度下P-RTV污闪电压比S-RTV高，说明更强的憎水性意味着更高的防污性能。此外，沿面闪络会导致P-RTV涂料憎水性暂时性的部分丧失，污闪电压幅值下降11.1%~21.1%，此部分丧失一段时间后可恢复，而S-RTV涂料憎水性的丧失部分却是不可恢复的；RTV涂料表面均有不同程度灼烧痕迹且放电痕迹分布在与高压端相连的绝缘子下表面，这是导致表面防污性能下降的因素之一。直流电压下RTV涂料表面灼烧痕迹明显，抗漏电起痕性能较弱。P-RTV综合性能优于S-RTV，因此实际使用应优先考虑P-RTV。研究结果对RTV涂料的研制和使用具有一定的指导意义。

Hydrophobicity and Flashover Characteristics Analysis of Various Types of RTV

Room temperature vulcanized silicone rubber （RTV） has good antifouling properties, which has been widely used in the power system, but different types of RTV coatings antifouling performances are unlike. Static contact angle of different RTV coatings were determined and the hydrophobicity recovery properties after pollution flashover and AC/DC flashover characteristics were tested and analyzed. The test results show that the hydrophobicity of long-acting RTV coating （P-RTV） is stronger than that of high self-cleaning RTV coating （S-RTV）； and under the same pollution degree, the pollution flashover voltage of P-RTV is higher than that of S-RTV, which shows stronger hydrophobicity means higher antifouling performance. In addition, surface flashover can cause the temporary loss of P-RTV hydrophobicity, which will lead flashover voltage amplitude decreasing 11.1 %-21.1%, while the loss of S-RTV coatings hydrophobicity is unrecoverable. The surfaces of RTV coatings all have burning marks in varying degrees distributed on the lower surface of the insulator connected with the high voltage, which is one of the factors causing anti-pollution performance decreasing. And the signs of burning on RTV surface are more obvious under DC voltage； its dielectric tracking performance is poor. Moreover, the comprehensive performance of P-RTV is better than that of S-RTV, so the priority of actual application should be given to P-RTV. The result has a certain guiding significance to the development and use of RTV coatings.