Design and Modal Analysis of End-Winding Support Systems in Induction Motors

The design of an electric motor must account for multiple structural requirements to ensure sufficient resistance against operational stresses and prevent premature failures. Among these considerations, frequency analysis of different components plays a critical role in evaluating their dynamic behaviour. This study investigates the modal characteristics of the end-winding region of a medium-power, four-pole induction motor. Due to the machine configuration, the dominant structural response under excitation corresponds to an eighth nodal diameter mode shape. To enhance vibration resistance, various supporting system designs were developed and analysed using modal analysis. Several alternatives were proposed based on the number of roping rows and the placement of aluminium support rings. Comparative frequency analysis revealed that using an aluminium annular ring roped around the coils significantly improves system stiffness and raises natural frequencies. The location of this ring was found to be a critical parameter, with positioning near the coil bends yielding superior results. Based on the results, the best-designed model demonstrated the highest natural frequencies and was identified as the most effective configuration.

کلیدواژه ها:

Induction motor ، end-winding ، modal analysis ، natural frequency