Abstract: Permanent magnet synchronous motors have the advantages of low speed, high torque, high power density, and high efficiency, making them ideal driving devices for large scraper conveyors and belt conveyors used in mining. However, in practical work, there are many heating problems that restrict the better development of permanent magnet motors. Therefore, it is generally adopted to set up cooling channels inside the casing to cool and dissipate heat through water cooling for the entire motor, However, there are significant differences in the heat dissipation of permanent magnet motors with different channel structures. Therefore, based on computational fluid dynamics (CFD) software, numerical simulation studies were conducted on the heat dissipation characteristics of permanent magnet motors under axial and circumferential Z-shaped water channel structures. Three dimensional geometric models of the casing and complex flow channels were extracted, and grid division was carried out using ICEM. Boundary condition settings were completed, and the pressure field, flow rate, and temperature field under different flow channel structures were obtained through simulation analysis, Analyzed the influence of different flow channel structures on the heat dissipation effect of the motor. The results show that there is a significant imbalance in the temperature of the casing in different areas of the casing. The temperature of the casing in the axial Z-shaped water channel shows a circumferential distribution imbalance, while the temperature of the casing in the circumferential Z-shaped water channel shows an axial distribution imbalance. Under the same flow rate, the pressure difference between the inlet and outlet of the axial Z-shaped water channel and the average flow velocity of the cooling level are significantly greater than those in the circumferential Z-shaped water channel. Due to the faster average flow velocity of the cooling level inside the axial Z-shaped water channel, The maximum temperature of the casing and cooling water channel is lower than that of the circumferential Z-shaped water channel 6K-7K, so the axial Z-shaped water channel has better heat dissipation effect and can better control the casing temperature. The research results provide theoretical basis and technical support for the optimization design of the complex flow channel structure of permanent magnet synchronous motors, improving the cooling and heat dissipation effect of the motor, and driving performance.