磁场强度波形畸变对交流磁滞回线形状的影响

Influence of the waveform distortion of magnetic field intensity on the shape of AC hysteresis loops

测量了软磁铁氧体环形样品在不同条件下的交流磁滞回线,发现磁滞回线形状随交流磁场强度H的幅值、频率而变化.交流磁滞回线形状的变化是由于磁场强度H波形畸变造成的,在弱交变场下,当磁感应强度B作正弦变化时,磁场强度H也作正弦变化,此时磁滞回线形状为椭圆;当磁场增强时,H-t曲线发生了不同程度畸变,且磁场强度越强,H-t曲线畸变程度越严重,此时磁滞回线变弯变尖,呈胖S形.通过理论分析及实验拟合对磁滞回线形状变化做出了解释.

AC hysteresis loops of soft ferrite ring sample are measured under different conditions.It is found that the shape of the hysteresis loops changes with the amplitude and frequency of AC magnetic field strength.The changes of the shape of the AC hysteresis loops are caused by the waveform distortion of magnetic field intensity H.In a weak AC magnetic field,when magnetic induction intensity B is changed sinusoidally,the magnetic field intensity H is also changed sinusoidally. At this time, the shape of the hysteresis loop is elliptical. When the magnetic field intensity increases, H-t curves show different degrees of distortion. The stronger the magnetic field is, the more severe the distortion of H-t curves is. At this time, the shape of hysteresis loops becomes bended and sharp, shows a fat “S”shape. These changes in the shape of hysteresis loops are explained through theoretical analysis and experimental fitting.