Calculation Method of Cable Ampacity Based on Field-circuit Combined Mode

Electricity is usually transmitted through power cables in densely populated areas. It is significant to predict the ampacity and temperature field accurately to ensure safe and economical operation of cables. In this paper, a field-circuit combination algorithm is proposed. The equivalent thermal circuit method and the finite difference method are effectively combined to calculate the temperature of cable and soil area respectively. This method is more accurate than the equivalent thermal circuit method and faster than the traditional numerical method. It is proved that the new method in this paper can meet the needs of engineering by comparing with the results of equivalent thermal circuit method in homogeneous soil and coordinate combination method in inhomogeneous soil respective.