Method and system for determining thermal parameter of single-core cable conductor

The invention provides a method and a system for determining a thermal parameter of a single-core cable conductor. The method comprises the following steps: layer equivalent insulating layers by taking a conductor shielding layer, an insulating layer and an insulating and shielding layer of the single-core cable conductor as the equivalent insulating layers, respectively establishing an infinitesimal cylinder wall transient thermal circuit model of each equivalent insulating layer and infinitesimal cylinder wall transient thermal circuit models of other layers of the single-core cable; and connecting the infinitesimal cylinder wall transient thermal circuit models of the equivalent insulating layers and the other layers of the single-core cable in series according to a practical structure of the single-core cable to form an optimized transient thermal circuit model of the single-core cable, thus obtaining the thermal parameter of the single-core cable conductor according to the optimized transient thermal circuit model. The transient thermal circuit model of the single-core cable is optimized, the thermal parameter of the conductor can be solved by using the optimized transient thermal circuit model, the accuracy can be obviously improved, and a calculation error of carrying capacity of the cable can be reduced.