Thermosetting plastic package type small solenoid valve coil AN1024

Accounting method for motor inductance, inductance coil, electromagnetic coil

1. Motor inductance accounting method Motor inductance accounting (perhaps reactance accounting, the difference between the two is an electrical angular frequency of 2×Txf) determines the function of the motor, which is the key parameter for motor analysis and design.

2. For motors with uniform air gap, such as asynchronous motors, because the magnetic potential wave and the magnetic density wave have the same shape, they differ only by an air gap permeability constant, so only the magnetic density wave needs to be integrated to obtain the flux linkage and inductance. For motors with uneven air gaps, such as synchronous motors and switched reluctance motors, the magnetic density wave depends not only on the magnetic potential, but also on the shape of the air gap. Because of the uneven air gap, it is more difficult to calculate the inductance. At this time, two methods can be selected. One is the finite element method. As long as the model is built, the software will actively calculate the magnetic density and inductance. But sometimes it is necessary to know the analytical solution of inductance, which is convenient for qualitative analysis of the motor. At this time, the so-called permeance function analysis method can be used. The analysis method of permeance function is to decompose the air-gap magnetic guided waves by Fourier to obtain constant terms, fundamental waves and high-order magnetic guided waves. In order to determine the Fourier coefficient in the air gap permeance function, it is necessary to use finite element method to check a family of air gap specific permeance curves. By determining the air gap permeance function, we can calculate the air gap magnetic density = air gap magnetic potential × air gap permeance function. When the air gap magnetic density is obtained, the flux linkage and inductance can be calculated by the same integration method as that of the air gap uniform motor.