低频叠加PWM波复合励磁下磁心损耗的测量与模型

Test and model of core losses under complex excitation of superimposing of low frequency and high frequency PWM waveforms

针对功率因数校正电路(PFC)和逆变器等的应用,分析低频和PWM波复合励磁工况下磁心损耗的特点,提出一种可独立控制低频和高频磁通密度分量,并能获得两种分量磁心损耗的测量方案。通过测量该工况下的动态磁滞回线,深入研究了各个高频周期的动态磁滞回线状态,得出了励磁和去磁过程中高频周期内低频和高频损耗分量面积的计算公式,从而实现了低频和高频损耗分量的分离和模型的建立。最后,通过实验验证了模型的准确性。

For PFC circuit and inverter applications,the characteristics of core losses under complex excitation of the superimposing of low frequency and high frequency PWM waveforms are analyzed. A test platform is established which can control the low frequency and high-frequency components of magnetic flux density individually. And the states of dynamic hysteresis loop of magnetics on every high-frequency cycle are researched through testing dynamic hysteresis loop under corresponding working condition. Furthermore,the theoretical calculation formulas for areas of low frequency and high-frequency components of core losses are given within the high-frequency cycle under exciting and resetting procedure. Therefore,the loss separation between the low frequency and high-frequency components can be accomplished and its model is then built. Finally the accuracy of the model is verified by the experiments.