METHOD FOR DETECTING PARTIAL DISCHARGE IN POWER CABLE OR POWER CABLE LINE

摘要

PURPOSE:To measure the partial discharge of a long cable at high sensitivity by providing a discontinuous part at an external metal shielding conductor other than both ends of power cable. CONSTITUTION:A discontinuous part 31 of an external metal shielding conductor 3 corresponding to a high frequency voltage is provided at an arbitrary place other than both ends of a power cable C. A voltage Vx or Vy caused by partial discharge which is generated between discontinuous end 31a or 31b of the shielding conductor 3 is measured. In this way, the voltage corresponding to a pulse voltage which is generated between a central conductor 1 and the shielding conductor 3 is obtained. The measured value of the voltage is large, and attenuation during propagation is small. Even in such a long cable, the partial discharge can be readily detected with the voltage Vx or Vy between the shielding conductor and the ground.