277 / 2018-09-25 11:33:30

HVDC Extruded Cable Space Charge Measurement Under Operating Condition with Temperature Difference

HVDC cable,space charge measurement,temerature gradient

Cross-linked polyethylene(XLPE) HVDC extruded cable has become one of the key technologies in the develop-ment of Energy Internet, where the domestic and international operation and construction lines are over 4000km and the highest voltage is up to ±320kV. However, the long-term performance evaluation of extruded HVDC cables is still on the principle of HVAC cable pre-qualification tests which cannot fully reflect the change of the insulation temper-ature gradient during load changing of DC cable system in operating. Furthermore, the interfacial effect of insula-tion/semi-conductive layer on space charge is much greater than that of insulation bulk in space charge evaluation on film and plate samples during HVDC cable development research, which neither cannot accurately show space charging characteristic of full size HVDC cables. The paper presents the HVDC extruded cable operation test and as-sessment system as well as full-size cable space charge measurement techniques under controlled temperature gradi-ent. The long-term performance evaluation test and space charge measurement of an ±160kV HVDC cable and ac-cessories under different operating conditions are carried out by using this test system and the results are briefly dis-cussed.