寄生参数效应的共模扼流圈集中参数建模

为分析传导EMI用共模扼流圈寄生参数的效应和预测EMI滤波器的高频特征,需要建立其寄生参数的模型,为此提出了基于阻抗测量实现共模扼流圈集中参数的建模方法,模型包括共模电感、漏感、绕组寄生电容等参数。基于阻抗测量,阐述求解寄生电容的基本原理;运用电路等效原理,将磁心的损耗等效为电阻的损耗,经适当简化,该电阻仅是频率的函数,将非线性的磁心损耗用一个与频率有关的电阻元件来等效,适合于电路的设计和仿真。最后通过样品实验,用所提出的方法建立了共模扼流圈的高频模型。

Lumped-parameter Model of Parasitic Effect for Common Mode Chokes

The high frequency model of common mode chokes based on measurement method is introduced.A basic princi- ple to extract the stray capacitance is illuminated with the measurement method.The loss of magnetic core had been con- sidered by a frequency dependent equivalent series resistor through proper predigestion,which is convenient to design and simulate circuit.Finally,the experiment had been completed with the method of constructing the high frequency model of common mode chokes.