Wen C.-L.,Chongqing Electrical Power Dispatch Center |
Liu J.-J.,Chongqing Electrical Power Dispatch Center |
Zhan H.,Chongqing Electrical Power Dispatch Center |
Zhang Y.,Chongqing Electrical Power Dispatch Center |
And 2 more authors.
Gaoya Dianqi/High Voltage Apparatus
Medium voltage cable terminations may soon lose their insulation because of the continuing action of high frequency harmonic voltage. The insulation breakdown depends on the electric field and temperature under high frequency voltage. In this paper, the effects of high frequency harmonic voltage on temperature and electric field of 35 kV cable terminations are investigated to understand the relationships between hot spot and electric field distribution. A high frequency and high voltage generator is applied to two types of cable terminations (stress grading type and geometric type). By means of the thermal images, distribution of temperature is analyzed under different voltage frequency and amplitude of voltages. With the increase in voltage frequency and amplitude, temperature of hot spot rises for stress grading termination, whereas the temperature change is not obvious for geometric termination. The location of the hot spot is related to the maximum value of electric field strength for stress grading termination. The research may facilitate the development of new type cable terminations with high frequency resistance. Source