Source:Kyotoku
As we all know, inductance is a commonly used device, and its essence is a group of coils, which are used to realize many functions
1 inductance L
Inductance L represents the inherent characteristics of the coil itself, which is independent of the current. In addition to the special inductance coil (color code inductance), the inductance is generally not specially marked on the coil, but with a specific name.
2 inductive reactance XL
The resistance of inductance coil to AC current is called inductive reactance XL, and the unit is Ohm. Its relation with inductance L and AC frequency f is XL = 2 π fL
3 quality factor Q
The quality factor Q is a physical quantity representing the coil quality. Q is the ratio of inductive reactance XL to its equivalent resistance, i.e. q = XL / R. The higher the Q value of the coil, the smaller the loss of the loop. The Q value of the coil is related to the DC resistance of the conductor, the dielectric loss of the framework, the loss caused by the shield or iron core, and the influence of high frequency skin effect. The Q value of the coil is usually tens to hundreds. Mining
The Q value of the coil can be increased by using magnetic core coil and multi thick coil.
4 distributed capacitance
The capacitance between turns of coil, between coil and shield, between coil and bottom plate is called distributed capacitance. The existence of distributed capacitance makes the Q value of the coil decrease and the stability become worse, so the smaller the distributed capacitance is, the better. The distributed capacitance can be reduced by using sectional winding method.
5. Allowable error:
The percentage of the difference between the actual and nominal inductance divided by the nominal value.
6 nominal current:
It refers to the current allowed to pass through the coil, which is usually represented by letters a, B, C, D and e respectively. The nominal current values are 50mA, 150mA, 300mA, 700mA and 1600ma.