超高压输电系统传递过电压的电磁暂态过程及特性分析

针对厂站操作过电压对大型发电设备的冲击问题,重点对超高压开关站中的操作过电压通过升压电力变压器传递的暂态过电压进行分析,研究了超高压输电系统传递过电压的电磁暂态过程及特性,分析表明,在升压变压器传递暂态过电压过程中,电磁感应过电压和静电感应过电压在升压变压器的低压侧叠加,共同对大型发电机绝缘安全构成威胁。分析了传递过电压对大型发电机造成的冲击程度,并对传递过电压的电磁暂态过程进行了仿真试验,其传递过电压所形成冲击电压幅值高达约2p.u.。仿真表明超高压开关站的操作冲击波通过升压变压器冲击大型水轮发电机组。

Electromagnetic transient process and characteristic analysis for over-voltage transferred from extra-high voltage power transmission systems

In order to protect the large generation equipment against the switching over-voltage,the law and characteristic of electromagnetic transient process of the over-voltage transferred from the extra-high power transmission system in power stations are studied,especially the electromagnetic transient process of the over-voltage transferred from the switchgear station through power transfor-mers.During the transient process of the over-voltage transferred through power transformers,the electromagnetic inductive over-voltage and the electrostatic inductive over-voltage are superposed at the low-voltage side of the power transformer,thus endangering the insulation of large generators.The transient process is simulated by tests and its impact on large generator is analyzed,in which 2 p.u.surge voltage has reached.The simulation shows that the switching operation of extra-high voltage switchgear station does strike large generators through power transformers.