【摘要】 变频器产生的高频重复激励脉冲会在电机定子绕组上产生不均匀且高幅值的过电压，从而加速电机绝缘系统老化甚至产生故障。本文基于暂态分析软件PSCAD/EMTDC，建立了2.5 MW永磁直驱发电机的三相定子绕组等效电路模型，并应用有限元方法计算了对应等效电路的分布参数。同时为了验证仿真计算结果的有效性，搭建了实验测试平台。结果表明：在三相脉宽调制脉冲电压的作用下，该永磁直驱风力发电机的定子绕组对地、线圈间以及匝间的过电压幅值沿电机接线端子到绕组中性点均呈现减小的趋势。实验测试结果进一步验证了三相定子绕组等效电路模型的准确性。更多还原

【Abstract】 The high frequency repetitive impulse generated by the inverter can lead to uneven overvoltage with high amplitude along the stator windings, which will accelerate the ageing of insulation system and even cause faults. On the basis of the transient analysis software PSCAD/EMTDC, the equivalent circuit model for threephase stator windings of 2.5 MW permanent magnet direct-drive generator was established, and the parameters of corresponding equivalent circuit were calculated by finite element method. Moreover, the experimental platform was built for verifying the validity of the calculation results. The results show that under the effect of three-phase pulse width modulation(PWM) pulse voltage, the amplitudes of the overvoltage to ground, coil to coil overvoltage, and turn to turn overvoltage of the stator winding for permanent magnet direct-drive wind generator show a decreasing trend from the connecting terminal of motor to the neutral point of winding. The experimental results further verify the accuracy of the equivalent circuit model of three-phase stator winding.更多还原