CAJ | 학술논문

研究了上海周边7条超高压与特高压直流系统中有一条或多条线路单极运行时，上海沪西等特高压变电站和上海500 kV电网的直流偏磁情况。电磁仿真计算各交流变电站的地电位分布与中性点偏磁电流，结果表明：多条直流线路单极运行时一条线路上的电流不会通过其他线路回流，特高压变电站的直流电流在多条线路同时单极运行时的数值等于单条线路单极运行时的代数和，向家坝-上海、锦屏-苏南、三峡-上海这3条线路单极运行时对沪西变电站的影响最大，使特高压变压器中性点偏磁电流超过5 A，约2.4Ω的变压器中性点串联电阻可较好地抑制沪西特高压变电站的直流偏磁电流。
연구료상해주변7조초고압여특고압직류계통중유일조혹다조선로단겁운행시，상해호서등특고압변전참화상해500 kV전망적직류편자정황。전자방진계산각교류변전참적지전위분포여중성점편자전류，결과표명：다조직류선로단겁운행시일조선로상적전류불회통과기타선로회류，특고압변전참적직류전류재다조선로동시단겁운행시적수치등우단조선로단겁운행시적대수화，향가패-상해、금병-소남、삼협-상해저3조선로단겁운행시대호서변전참적영향최대，사특고압변압기중성점편자전류초과5 A，약2.4Ω적변압기중성점천련전조가교호지억제호서특고압변전참적직류편자전류。
The DC magnetic biasing in Shanghai UHVAC substations and that in Shanghai 500 kV power network are researched when one or more in seven EHVDC and UHVDC power transmission lines around Shanghai are operated in monopole operation mode. Results of electromagnetic simulation on ground potential distributions in AC substations and biasing currents through neutral points show that when multi DC transmission lines are operated in monopole operation mode, the current of one line will not backflow via other lines; when multi DC lines are operated in monopole mode simultaneously, the value of DC current biasing in UHVAC substations is equal to algebraic sum of the DC current biasing of each DC line solely operated in monopole mode;the most serious impact on the West Shanghai UHVAC substation is caused by monopole operation mode of three EHVDC and UHVDC lines, namely the EHVDC transmission line from Three Gorges to Shanghai, the UHVDC transmission line from Xiangjiaba to Shanghai and the UHVDC transmission line from Jinping to Suzhou, and it makes the DC biasing current at neutral point exceeding over 5 A; the transformer neutral point series-resistor with the value about 2.4 ohm can suppress the DC magnetic biasing current in West Shanghai UHVAC substation better.