Design of the forced water cooling system for a claw pole transverse flux permanent magnet synchronous motor

This paper presents a detailed finite element analysis-based design procedure of the forced water cooling system for a low voltage claw pole transverse flux permanent magnet motor (TFPM), which is used in marine propulsion systems. Iron and copper losses density distributions are obtained using commercial finite element method software JMAG 10.5. Surface water cooling system, with spiral cooling ducts passing through the aluminum hosing of the stator, is chosen as the proper cooling system. To prevent any thermal and electrical unbalanced situation, for each phase separate water input and output are considered. Dimensions of the cooling ducts, as well as the velocity of water flowing through these ducts are calculated in a way that makes the water flow completely turbulent, having the right speed for cooling purposes. Number of required cooling ducts for an acceptable temperature distribution, below the thermal limits of motor, is determined by finite element thermal analysis. To consider the worst case scenario, a number of assumptions are made in the thermal analysis of the motor.