为了减少电力系统正常运行时电流和电压的不对称性，原则上高压架空线路应采用换位措施。
In order to decrease the asymmetry of current and voltage of the power system, the high voltage transmission lines should be transposed in principle.
本文叙述超高压变电所和架空线路中相间绝缘操作冲击试验的基本结果。
The paper describes the basic switching impulse test results of phase-to-phase insulation in EHV substations and overhead lines.
高压直流输电系统架空线路只需正负两 极导线，可实现大功率、低损耗、长远距离电力的直接输送；
The overhead line of HVDC power transmission system needs positive and negative leads only, allowing for high power, low loss and long distance power transmission;
高压直流输电系统架空线路只需正负两 极导线，可实现大功率、低损耗、长远距离电力的直接输送；
The overhead line of HVDC power transmission system needs positive and negative leads only, allowing for high power, low loss and long distance power transmission;
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