Advanced unsteady three-dimensional thermal modeling of a line start permanent motor using a heat loss mapping method

This paper describes thermal modeling of a line start permanent magnet (LSPM) motor using a computational flow dynamics method. First, 2-dimensional electromagnetic design is carried out in order to comprehend heat losses at winding, stator, rotor and cage. New coupling method called Heat mapping method (HMM) will be introduced which converts 2-D information of electromagnetic domain to 3-D information of thermal domain. Transient thermal analysis under rated operating conditions is performed to identify the load saturation time and temperatures in the LSPM motor. Experimental results are collected under the same operating conditions and computational results are verified against the experimental data. Finally, thermal path analysis at a steady-state is conducted to figure out the direction and magnitude of heat flux in the LSPM motor. These results can be useful to design effective cooling systems of electrical motors