Basic properties of magnetic materials
In the design of soft magnetic devices, the voltage and current characteristics of the device must be determined according to the requirements of the circuit. The voltage to current characteristics of the device are closely related to the geometry and magnetization of the core. The designer must be familiar with the magnetization process of the material and master the relationship between the magnetic parameters of the material and the electrical parameters of the device. The design of soft magnetic device usually consists of three steps: the correct selection of the magnetic material; reasonably determine the shape and size of the magnetic core; the magnetic parameters according to the requirements, the electrical parameters of the corresponding simulation core working condition.
Saturation magnetic induction intensity Bs: its size depends on the composition of the material, and its corresponding physical state is the material inside the magnetization vector neatly arranged.Residual magnetic induction intensity Br: the characteristic parameter on the hysteresis loop, and the B value of H when it goes back to 0.
The magnetic material is composed of ferromagnetic or ferrimagnetic material, in the magnetic field under the action of H, there will be magnetization M or magnetic induction intensity corresponding to the B, they change with the magnetic field strength H curve known as the magnetization curve (M ~ H or B ~ H curve). The magnetization curve is nonlinear in general and has 2 characteristics: magnetic saturation and hysteresis. When the magnetic field intensity H is large enough, the magnetization M reaches a certain saturation value Ms, continue to increase H, Ms remained unchanged; and when the value of M reached saturation, the external magnetic field H is reduced to zero, M does not restore to zero, but along the MsMr curve. The working state of the material is equivalent to the M to H curve or a point on the B to H curve, which is often referred to as the work point.
