EXPERIMENTAL AND NUMERICAL INVESTIGATION OF THERMAL FIELD FOR A MOTOR AND RELATED FACTORS SENSITIVITIES USING COMBINED CFD-TAGUCHI METHOD

Over-temperature is a fatal problem when a motor is running. In this work, the temperature and temperature rise of the motor are investigated experimentally and numerically. The experiment is conducted by means of both voltmeterammeter method and embedding thermal resistors, to obtain the mean temperature and the local temperature of the stator coils, respectively. The numerical calculation is carried out to study the temperature field of the stator and the rotor, which agrees well with the experimental result. What's more, the sensitivity analysis of eighteen factors to the temperature is investigated using combined CFD-Taguchi method. The main conclusions are drawn. Firstly, according to the numerical results, the maximal temperature and the maximal temperature rise at rated speed are 143 ℃ and 99 K, respectively. The values are 145.8 ℃ and 90 K, according to the experimental results, which are lower than the temperature allowed, 180℃ and temperature rise allowed, 125 K. Secondly, the sensitivity analysis results suggest that the key factors influencing the temperature are in sequence the ambient temperature, the copper loss, the thickness of the layers, the outside convection heat transfer coefficient of crate, the iron loss at the tooth and thermal conductivity of the insulation. The contact thermal resistance and the thermal conductivity of the core in axial direction have little influence on the temperature. The rank to the temperature rise is similar except the ambient temperature, which has little effect on the temperature rise.