A Novel Temperature Rise Calculation Method of Electromagnet DC Coil

The commonly used DC coil wounded around the electromagnet winding skeleton, acts as the key electro‐magnetic conversion element, is formed by enameled wire with poor heat dissipation. The electric conductivity of the conductors will be greatly influenced by the high temperature generated from coil's internal heat, especially for long‐term work conditions. Thus, in order to calculate the DC coil's temperature accurately and effectively during the primary design process of the electromagnet, a novel temperature rise calculation method for the steady and transient is proposed in this paper. First, the geometric and resistance models of the enameled wire are established, according to the spatial arrangement and the resistance‐temperature characteristics. Secondly, the temperature rise of the electromagnet coil is calculated theoretically, based on the steady and transient heat dissipation equations. Thirdly, the Thermal‐Electric simulation model is established, which is used to simulate and analyze the temperature of the electromagnet coil changing with excitation voltage. Finally, a temperature rise test platform of the electromagnet coil is established, the steady and transient temperature rise under various conditions is measured. The temperature rise results of theoretical calculation, simulation and experiment show good agreement with each other. It gives significant guidelines to the design and optimization processes of such electromagnet DC coil. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.