Executive Summary : | Electric vehicles (EVs) are becoming increasingly popular in India, with many utilizing permanent magnet synchronous motors (PMSM) due to their high torque and power density. PMSM motors consist of a rotor and stator, with the rotor containing strong permanent magnets embedded in a laminated steel structure. The stator is made of laminated iron layers with slots through which copper wire is wound, covered with electrical insulation. The current in the stator coils is modulated to produce a rotating magnetic field that is tracked synchronously by the rotor. A portion of the power supplied to the motor (usually less than 10%) is dissipated as heat. Heat dissipation mechanisms in PMSM include Joule (DC) losses in the copper windings, hysteresis and eddy current losses in the stator iron, AC losses in the copper windings, Magnet losses in the rotor, mechanical, windage, and other losses. The thermal management system transfers the heat generated in the motor to the heat sink to ensure the materials used do not exceed their operational limits. This project aims to develop a scalable two-phase loop thermosyphon for passive thermal management systems of PMSM motors used in electric vehicles. The advantages of this technology include passive thermal transport, high heat transfer coefficients due to evaporation/boiling and condensation, not subjected to the capillary limit, liquid and vapor flow in separate tubes, and an isothermal evaporator due to boiling/evaporation. The work will be carried out in phases: development, fabrication, testing of single horizontal evaporator LTS, development of network mathematical model predicting and correlation with experimental data, and development, fabrication, and testing of a multiple evaporator LTS. |