Design and Thermal Analysis of a 300 Watt BLDC motor

This paper presents the mechanical design and transient thermal analysis of a permanent magnet Brushless DC motor to be replaced with an induction motor and its gearbox for a propulsion application requiring 300 W and 220 RPM. This work presents a suitable method for direct motor drive design. The critical design criterion is based on magnet demagnetization. The motor has magnets inset into the surface of the rotor to give a maximum field-weakening range. A prototype model is fabricated based on the presented method. Analytically based lumped circuit method for thermal analysis has been used to simulate the motor. Simulation results are compared with practical measurements. The comparison of the results shows that the presented method has a high efficiency in design and thermal analysis of BLDC motors.