变电站直流偏磁综合仿真方法分析

Analysis of Comprehensive Simulation Method of DC Bias in Substations

针对不同工况下直流输电入地电流造成的电磁兼容问题,结合四极法与大地电磁法对伊克昭—沂南直流工程中鄂托克前旗地区大地电阻率进行测量与反演,运用自研软件,结合提出的混合优化算法,对线路、变电站及其他电网部分建立相应的仿真模型,同时建立鄂托克前旗地区电网直流分布模型,对该地区重点变电站直流偏磁中性点电流实测值与仿真值进行对比,对鄂托克前旗地区变电站在不同直流入地电流下的直流偏磁影响进行计算与评估。结果表明,该直流工程对周边变电站的直流偏磁问题影响不显著,计算结果及仿真方法具有工程参考意义。

In different work conditions,the ground current of DC transmission in different operating conditions has caused many serious electromagnetic compatibility problems.The earth resistivity in Otog Front Banner area is measured and inverted through combining the four-pole method with the magnetotelluric method for the Yikezhao-Yinan DC project.Simulation model for lines,substations and other parts of the power grid is established through using self-developed software and combining with the Hybrid optimization algorithm presented in this paper.The DC distribution model of the power grid in the Otog area is established.The influence of DC bias in substations with different ground current of DC transmission is calculated and evaluated through comparing the measured value of the DC bias neutral current with the simulated value at the key substation in Otog Front Banner area.The results show that the DC project has no significant effect on the DC magnetic bias of the surrounding substations.And the calculation result and the simulation method have referential significance in projects.