Design and Thermal Analysis of Cooling System for High-Power Density Motor Based on Air-flow

A great challenge due to recent advances in Artificial Intelligence (AI) is the construction of sophisticated and flexible AI-driven robots. Flexibility requires these robots to be light-weighted. To achieve this, robots are constructed with small-sized components of which electric motor is part of it. Unfortunately small-sized motors are faced with the problem of overheating. In this paper, a new structural design for electric motors, with cooling support based on air-flow, is presented. This is aimed at increasing the rate of heat convection in the motor, thereby cooling it. The new structure provides cooling to the motor without increase in weight and size. The cooling structure is investigated on a high power density motor rated at 2kW, 40Arms, 15000rpm speed with 2 pole pairs surface permanent magnet. A detailed thermal analysis of the motor is investigated by developing an analytical thermal model based on Lumped parameter and Finite Element Analysis (FEA). The strucute is validated by comparing the results of the analytical model with Computational Fluid Dynamics (CFD) simulation. The comparison shows a significant reduction of temperature due to the cooling structure.

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