西电大幅送电下广东内部断面热稳问题分析

Analysis of the Thermal Stability of the Internal Section of Guangdong under the Large Supply of Western Electricity

近年来随着广东负荷逐步攀升、西电送广东电力逐年加大,同时由于广东电网短路电流超标导致部分线路停运,导致输电线路潮流加重,输电线路热稳定问题已经逐渐成为广东电网最主要问题。特别是在迎峰度夏期间,广东负荷较高、西电大幅度送电,多条输电通道处于压极限运行的状态,若此时电网发生大直流双极闭锁故障,将会导致多个输电断面超热稳定限值运行,电网调控难度增大,存在错峰限电风险。针对该问题,提出了一种基于转移比的断面查找方法,并利用灵敏度分析了普侨、楚穗、兴安三大直流双极闭锁后对广东内部断面的越限的调控方法,按照灵敏度及调控速度进行分析排序,为度夏期间直流闭锁导致的广东内部断面越限调控提供有效的依据和建议,提高了调控的准确性和快速性,确保了广东电网安全稳定运行。

In recent years, with the gradual increasing of Guangdong load and transmission of Guangdong electric power from west to east, the power flow of some transmission line are increasing.At the same time, due to the short-circuit current exceeding the standard of Guangdong power grid which causes some of the lines are outage, the thermal stability problem has gradually become the main problem of Guangdong power grid. Especially during the summer peaks for the reason that Guangdong load is comparatively higher and so is the supply of Guangdong electric power from west to east , a plurality of transmission channels operate under the the pressure limit. If the power of large DC bipolar block faults happen it will lead to serious problems such as multiple transmission section operate over the thermal stability limits, power control difficulty increases and maybe causes peak power rationing risk. To solve this problem, this paper proposes a research method based on section transfer ratio, and use the sensitivity to analyse the method to the problem that Guangdong internal section is over the limit after Pu Qiao, Chu Sui, Xingan’s three largest DC bipolar block. It also analyzes and sorts the method according to the sensitivity and regulating speed which provides effective gists and suggestions for the control of the problem that Guangdong internal section is over the limit if DC bipolar block faults during the summer peaks, improves the control accuracy and rapidity and ensures the safe and stable operation of Guangdong power grid.