220kV岸电工程海陆互联输电线路操作过电压研究——以秦皇岛32-6、曹妃甸11-1油田群岸电工程为例

Study on switching overvoltage of 220 kV shore power project sea-land interconnected transmission lines:Taking QHD32-6 and CFD11-1 oilfield group shore power engineering as an example

秦皇岛32-6、曹妃甸11-1油田群岸电应用工程输电线路形式复杂,以高电容特性的陆缆及海缆线路为主,同时输电线路较传统供电模式距离增加、电压等级提高,系统过电压现象显著。为了明确该项目高压输电系统是否存在过电压风险,以工程实际为基础,对秦皇岛32-6、曹妃甸11-1油田群岸电工程线路的操作过电压问题进行了研究。采用电磁暂态仿真软件ATP-EMTP对该岸电项目的电力系统进行仿真,根据相关电气设备的参数及特性,搭建了220 kV海陆互联电力系统等效模型,分析了220 kV空载线路合闸、重合闸及分闸情况下的过电压水平,同时针对并联电抗器及避雷器对过电压的抑制作用进行了分析。结果表明,3种工况下,重合闸操作过电压水平最高且各工况下过电压最大值均出现在海缆末端;并联电抗器及避雷器对操作过电压均有抑制效果;该区域操作过电压无论是否设置过电压抑制措施,均处于规定的安全限值内,不存在过电压风险。本研究为岸电工程的安全稳定运行提供了参考。

The forms of transmission lines for shore power application projects of QHD32-6 and CFD11-1 oilfield group are complex, mainly composed of land cables and submarine cables with high capacitance characteristics. At the same time, the distance and voltage level of transmission lines are increased compared with traditional power supply modes, and the power system overvoltage is significant. In order to determine whether there is any overvoltage risk in the high-voltage transmission system of the project, the switching overvoltage problem of the shore power engineering lines of QHD32-6 and CFD11-1 oilfield group was studied based on the engineering practice. The power system of the shore power project is simulated with the electromagnetic transient simulation software ATP-EMTP. According to the parameters and characteristics of relevant electrical equipment, an equivalent model of the 220 kV sea-land interconnected power system is built, and the overvoltage level under the conditions of closing, reclosing and opening of the 220 kV no-load line is analyzed. At the same time, the restraining effect of the shunt reactor and lightning arrester on overvoltage is analyzed. The results show that under the three working conditions, the overvoltage level of reclosing operation is the highest, and the maximum overvoltage value occurs at the end of the submarine cable under each working condition;shunt reactor and lightning arrester have restraining effect on switching overvoltage;whether overvoltage suppression measures are set or not, the switching overvoltage in this area is within the specified safety limit, and there is no overvoltage risk. This study provides a reference for the safe and stable operation of shore power projects.