Measurement and Research of DC Magnetization Curves Based on DC Excitation Method

The DC magnetization characteristics of magnetic materials are difficult to be accurately measured in a wide range. In this paper, the DC excitation method is proposed to measure the intrinsic DC magnetization curve of magnetic materials, the measuring principle is analyzed in detail and the measuring platform is built, the on-off time of the switch is controlled reasonably through the communication of the host and lower computer, the voltage and current are sampled by high-precision sampling instrument and then process the data. Based on the measurement platform, the error sources are analyzed in detail and achieve a wide range of magnetic material DC magnetization curve measurement. Finally, the feasibility and accuracy of DC excitation method are verified by using air-core inductors whose permeability is close to vacuum permeability, the DC magnetization curves of ferrite and magnetic powder cores are measured based on the established measuring platform, the DC magnetization characteristics of the two magnetic materials are compared with the measured results of large signal AC method.