摘要: SPWM逆变器在工作时产生共模电压,会诱发电机轴电压,引起轴电流,可能损坏电机轴承。文章运用JMAGdesigner软件建立了永磁同步电机模型和轴承模型,对电机内部的耦合电容和轴承电容进行计算,重点针对电机内部几何尺寸和端部绕组对耦合电容的影响进行研究。结果表明:气隙宽度和槽口宽度对定、转子之间耦合电容Crf影响很大,但齿顶高和绕组绝缘厚度对其影响可忽略不计;气隙宽度、齿顶高、绕组绝缘厚度和槽口宽度均对定子绕组和转子之间的耦合电容Csr有一定影响;槽口宽度和定子绕组绝缘厚度对定子绕组和定子之间的耦合电容Csf有影响;Csf和Csr的大小与端部效应有很大关系。上述结论对进一步深入研究永磁同步电机轴电流具有重要参考价值。 关键词:永磁同步电机;共模模型;耦合电容
Abstract: SPWM inverter will generate commonmode voltage at working status, the common mode voltage induced shaft voltages, and common mode currents may damage the motor shaft bearing. In this paper, the PMSM model was established by JMAGdesigner software. The thesis calculated the bearing capacitor and coupling capacitor inside the motor, focusing on research of the coupling capacitance's influence produced by the geometry and end winding of motor. The results show that the air gap width and notch width have a great influence on the coupling capacitors Crf between stator and rotor, but the influence of addendum and winding insulation thickness can ignore; Air gap width , addendum , winding insulation thickness and width of the slot have a certain impact on both the coupling capacitance Csr between the rotor and the stator winding; Slot width and thickness of the winding insulation have an effect on the coupling capacitors Csf stator windings and stator. The value of Csr and Csf have a great relationship with the end effect. The above conclusion brings important reference value for the further research of shaft currents of permanent magnet synchronous motor. Key words: permanent magnet synchronous motor; commonmode model; coupling capacitor |