In this paper, a deep slot universal motor is designed for electric power tools. The deep slot structure can reduce the cost of universal motor materials and improve production efficiency. A mathematical model of a universal motor is established and a simulation model is established by MagNet finite element software. Then, the static magnetic field distribution and load characteristics of the deep slot universal motor are analyzed. Different methods are adopted to improve the commutation spark of a deep slot universal motor. Finally, three 550-W and 9500-rpm prototype motors are tested. Simulation and experimental results indicate that an uneven air gap, brush offset by a certain angle, as well as different turns of the lead coil and the lag coil can effectively improve the commutation spark of a deep slot universal motor.

中文翻译：

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电动工具深槽万能电机的设计与研究

本文针对电动工具设计了一种深槽通用电机。深槽结构可降低通用电机材料成本，提高生产效率。建立了通用电机的数学模型，并通过MagNet有限元软件建立了仿真模型。然后，分析了深槽通用电机的静磁场分布和负载特性。采用不同的方法来改善深槽通用电机的换向火花。最后，测试了三个 550-W 和 9500-rpm 原型电机。仿真和实验结果表明，不均匀的气隙、一定角度的电刷偏移以及超前线圈和滞后线圈的不同匝数可以有效改善深槽通用电机的换向火花。