雷击杆塔塔顶时导线上感应电压敏感性分析

为解决现有规程计算雷击高压输电线的高杆塔塔顶时导线上感应电压误差较大的问题,基于 Wagner提出的场抵消法理论,利用拟静电场法将电磁场的复杂计算转换为拟静电场来处理,通过大量的计算推导出感应过电压的经验公式,并与国内外其它经验公式比较。雷击塔顶时导线上感应过电压的敏感性分析结果表明,上升先导长度、雷电流幅值、导线高度等参数对感应过电压的影响显著;感应过电压波形的研究表明雷击塔顶时绝缘子两端过电压的感应分量和注入分量的峰值并非同时出现,在雷电过电压中感应分量的影响有限,不宜过分夸大。

Sensitivity Analysis of Lightning Performance Calculations for Transmission Lines

For solving the calculation error of line induced-o ve rvoltage in existing regulation when lightning strikes the tower top of high vol tage line, based on Wagner Field-Cancellation Method, applying simulating stati c electric field theory, the complicate calculation is converted to processing s imulating static electric field, and using a large amount of calculation, experi ence formula of calculating induced-overvoltage is deduced and then is compared with other formulas. Sensitivity analysis is done and the conclusion indicates that induced-overvoltage is more sensitive to the change of the length of upwar d leader, the peak value of lightning current and the height of transmission lin e and so on. According to the research of induced-overvoltage wave, it is point ed out that when the tower is struck by lightning, the peak values of induced vo ltage across the insulator string and the injected current do not appear at the same time, and the effect of induced value is limited and should not be magnifie d.