Temperature Field Analysis and Cooling Structure Optimization for Integrated Permanent Magnet In-Wheel Motor Based on Electromagnetic-Thermal Coupling

Aiming at the impact of heat generation and temperature rise on driving performance a permanent magnet (PM) motor, taking PM in-wheel motor (IWM) for electric vehicles as an object, research is conducted into distribution electromagnetic–thermal effect cooling structure optimization. Firstly, coupling model considering electromagnetic harmonics established using subdomain Bertotti’s iron loss separation theory. Combined with finite element (FE) simulation by Ansoft Maxwell software platform, winding copper loss, stator core eddy current under action complex magnetic flux are analyzed, transient each component obtained through coupling. Secondarily, influence waterway parameters dissipation PM-IWM analyzed thermal-fluid coupled relationship. On basis, optimization design carried out to improve system based proposed chaotic mapping ant colony algorithm metropolis criterion. The comparison before after shows that key components significantly improved, average convection transfer coefficient (CHTC) increased 23.57%, peak reduced from 95.47 °C 82.73 °C, decreased 14.26%, thus demagnetization risk in improved comprehensively. results can provide some theoretical technical support structural water-cooled motor.