考虑短路电流直流分量的福建沿海地区220 kV电网运行方式研究

Study on the Operation Mode of 220 kV target grid in Fujian Coastal Area Considering the DC Component of Short-circuit Current

目前电网规划短路电流计算分析仅关注短路电流交流分量,但随着新版《电力系统安全稳定导则》的贯彻执行,断路器的开断能力还应考虑短路电流的直流分量。基于福建沿海地区220 kV目标网架,本文分析比较福建沿海地区220 kV目标网架采用不同运行方式下的断路器实际开断能力,结果表明:采用500 kV站主变2-2分列运行方式可有效降低短路电流直流分量,进而保证220 kV母线短路电流交流分量有效值在断路器实际开断能力内。

At present,the calculation and analysis of short-circuit current in power grid planning only focus on the AC component of short-circuit current,but with the implementation of the new version of Guidelines for Safety and Stability of Power Systems,the breaking capacity of circuit breakers should also consider the DC component of short-circuit current.Based on the 220 kV target grid in the coastal area of Fujian,this paper analyzes and compares the actual breaking capacity of circuit breakers under different operation modes for the 220 kV target grid in the coastal area of Fujian.The results show that the DC component of short-circuit current can be effectively reduced by adopting the 2-2 separate operation mode of 500 kV substation main transformer,so as to ensure that the effective value of AC component of short-circuit current of 220 kV bus is within the actual breaking capacity of circuit breaker.