CAJ | 학술논문

±800 kV天-中特高压直流工程在调试期间，为研究天中直流在单极大地方式运行时对新疆电网变压器直流偏磁的影响，新疆电网进行了变压器直流偏磁带电测量工作，尤其是对天山换流站所在的哈密地区电网直流偏磁进行了多点测量，并通过交流电网直流电流分布计算软件仿真计算分析新疆哈密电网变压器直流分布的情况。仿真表明，在天中直流大功率单极大地运行时，天山换流站周边近区的变电站中性点接地的变压器直流电流较大，实测发现某些天山换流站接地极周边近区变压器中性点的偏磁电流较大，与仿真结果基本相符合，严重威胁主变压器偏磁运行，后期通过在直流电流过大的主要变压器加装了直流偏磁抑制装置，大大降低了变压器中性点的偏磁电流，提高了哈密地区电网的安全性和可靠性。
±800 kV천-중특고압직류공정재조시기간，위연구천중직류재단겁대지방식운행시대신강전망변압기직류편자적영향，신강전망진행료변압기직류편자대전측량공작，우기시대천산환류참소재적합밀지구전망직류편자진행료다점측량，병통과교류전망직류전류분포계산연건방진계산분석신강합밀전망변압기직류분포적정황。방진표명，재천중직류대공솔단겁대지운행시，천산환류참주변근구적변전참중성점접지적변압기직류전류교대，실측발현모사천산환류참접지겁주변근구변압기중성점적편자전류교대，여방진결과기본상부합，엄중위협주변압기편자운행，후기통과재직류전류과대적주요변압기가장료직류편자억제장치，대대강저료변압기중성점적편자전류，제고료합밀지구전망적안전성화가고성。
During the commissioning of ±800 kV Tian-Zhong HVDC project , in order to study its impacts on DC magnetic bias of transformers in Hami Power Grid , the live detection for DC magnetic bias of transformers is carried out in XinJiang Power Grid, especially the multi -point measurement is done in Hami Power Grid where the Tianshan DC converter station is , and the calculation software for DC current distribution simulation analysis in ac power grid is used to simulate the distribution of the DC current of transformers in Hami Power Grid .The simulation shows that , when Tian-Zhong HVDC project transports high power with monopole earth mode , the DC current of neutral grounding transformers which are near to Tianshan DC con-verter station is larger , and the measured results also give that the grounding transformer in some stations which are not far from Tianshan DC converter station has a larger magnetic bias current in neutral point , which is consistent with the simulation results.At last, DC magnetic bias suppression devices are added to the station where has the large neutral DC current .The proposed method greatly reduces the DC magnetic bias current of transformers , which will improve the security and reliability of power grid in Hami district .