【目的】本文提出一种用于5.5 kW变频供电鼠笼式感应电机的转子导条消谐槽结构,用于改善转子导条电流密度分布,并尽可能避免槽口局部热点问题。【方法】首先从磁势和磁导出发,分析了感应电机气隙磁场分量和导条感应谐波电流,根据趋肤效应计算了不同谐波电流的透入深度;其次,根据转子槽口几何模型,建立了单个导条载流面积随消谐槽形状和参数变化的数学模型,并提出基于该数学模型和少量仿真数据的消谐槽优化设计流程;最后,通过仿真验证,确定了针对该感应电机的最优转子消谐槽参数。【结果】通过仿真分析发现,空载工况下,转子消谐槽可降低40.9%的谐波铜耗;满载工况下,可降低5.5%的谐波铜耗;且导条载流面积仅下降0.94%,故两种工况下消谐槽均不会显著影响其他电磁性能。【结论】本文所提转子消谐槽可以大幅降低转子谐波铜耗,使导条电流分布更加均匀,能有效降低局部热应力和高负载率电机温升,适用于电机频繁起停或电源包含谐波的工况。

[Objective] This paper proposes a harmonic elimination slot structure for the rotor bars of a 5.5 kW inverter-fed squirrel-cage induction motor, aiming to improve the current density distribution in the rotor bars and minimize local hot spots near the slot openings. [Methods] The analysis was initially conducted based on magnetomotive force and magnetic permeability to examine the air-gap magnetic field components and induced harmonics current in the rotor bars of the induction motor. The penetration depths of different harmonics current were calculated according to the skin effect. Subsequently, a mathematical model was established for the current-carrying area of individual bars as a function of harmonic elimination slot geometry and parameters, derived from the rotor slot opening geometric model. An optimization design process for the harmonic elimination slots was proposed by combining this mathematical model with limited simulation data. Finally, the optimal parameters for the rotor harmonic elimination slots of the specified induction motor were determined through simulation verification. [Results] Through simulation analysis, it was found that under no-load conditions, the rotor harmonic elimination slots reduced harmonic copper losses by 40.9%; under full-load conditions, a reduction of 5.5% was achieved. Additionally, the current-carrying area of the bars decreased by only 0.94%, indicating that the harmonic elimination slots did not significantly affect other electromagnetic performance in both operating conditions. [Conclusion] The proposed rotor harmonic elimination slots in this paper can significantly reduce rotor harmonic copper losses, leading to a more uniform current distribution in the bars. This effectively mitigates local thermal stress and temperature rise in high-load motors, making it suitable for motor operating conditions with frequent start-stop cycles or power supply containing harmonics.

国家自然科学基金项目(52177041)；2025开放课题(HLZDSY2025002)