Features of Determining the Long-Term Permissible Current of Cable Lines in a Cable Channel

The question of determining the long-term permissible currents for cable lines laid in cable channels is considered in this paper. Analysis of heat sources that must be taken into account when calculating the permissible current is given. Options for determining the permissible current, based on the formulas presented in the regulatory documents, are considered. A mathematical model of heat transfer processes in an underground cable channel, which allows taking into account the influence of neighboring operating cable lines on the temperature of the conductive core, is constructed. The temperature distribution fields in the channel are obtained. The dependences of the long-term permissible line current on the load of one and two adjacent lines are obtained. The algorithm of the operator's work with the database of load modes, in order to find new long-term permissible line currents when the load of one of the lines changes, is developed.