Phone: 86-29-88685333
Mobile: 86-13620067891
E-mail: fks@fks-coils.com
Add:C2 Building, Western Cloud Valley, Fengxi New Town, Xixian New Area, Xi'an City, Shaanxi Province, China
Mobile: 86-13620067891
E-mail: fks@fks-coils.com
Add:C2 Building, Western Cloud Valley, Fengxi New Town, Xixian New Area, Xi'an City, Shaanxi Province, China
Chinese biggest factory of Air Core Coil shared the fuction of air core coils
Time: 2022-10-27 Source: Power Magnetic Components Wholesale Author: Terry Jin
The self-induced electromotive force in the air core coil is always resistant to the current change in the coil. The air core coil has a blocking effect on the alternating current, and the size of the blocking effect is called the inductive reactance xl, and the unit is ohm. Its relationship with inductance l and alternating current frequency f is xl=2πfl.
2. Tuning and frequency selection
The air core coil and the capacitor are connected in parallel to form an lc tuning circuit. That is, the natural oscillation frequency f0 of the circuit is equal to the frequency f of the non-AC signal, then the inductive reactance and capacitive reactance of the loop are also equal, so the electromagnetic energy oscillates back and forth in the inductor and capacitor, which is the resonance phenomenon of the lc loop. During resonance, the inductive reactance of the circuit is equal to and opposite to the capacitive reactance, the inductive reactance of the total loop current is the smallest, and the current is the largest (referring to the AC signal of f=“f0”). An AC signal of frequency f is selected.
The main parameters of the air core coil
1. Inductance
The inductance L is an inherent characteristic of the coil itself and has nothing to do with the current. Inductance is generally marked with a specific name.
2. Inductive resistance
The magnitude of the resistance of the inductive coil to the alternating current is called the inductive reactance XL, and the unit is ohm.
3. Quality factor
The quality factor Q is a physical quantity that represents the quality of the coil, and Q is the ratio of the inductive reactance XL to its equivalent resistance, namely: 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 wire, the dielectric loss of the skeleton, the loss caused by the shield or iron core, and the influence of the high-frequency skin effect. The Q value of the coil is usually tens to hundreds.
4. Distributed capacitance
The capacitance that exists between turns and turns of the coil, between the coil and the plate, and between the coil and the shield is called distributed capacitance. The existence of distributed capacitance reduces the Q value of the coil and deteriorates the stability, so the smaller the distributed capacitance of the coil, the better.
Winding method of air core coil
1. Single-layer winding method
The single-layer winding method is to wind the turns of the air core coil on the outer surface of the insulating pipe in a single-layer manner. The single-layer winding method is divided into indirect winding and tight winding. Indirect winding is generally used for some high-frequency resonance circuits. , because the winding method in this way can reduce the capacitance of the high-frequency resonance line graph, and at the same time stabilize some of its characteristics. The tight winding method is based on some coils with a smaller range of resonant coils.
2. Multilayer winding method
The inductance of the coil is relatively large. The winding method of the coil is a multi-layer winding method. The multi-layer winding method includes two types: dense winding and honeycomb winding. The dense winding method is arranged closely and needs to be distributed layer by layer. The capacitance generated by the coil it winds is relatively large. The honeycomb winding method is arranged at a certain angle. Its arrangement is not very flat, but compared with the tight winding method, its capacitance is relatively small. For some high-voltage resonant circuits, when winding the air-core coil, it is necessary to match the current value and the withstand voltage between the coils. When we wind the air-core coil, we also need to consider the heat of the coil.
FKS COILS offers many air core coils with different size. we partner with every customer to help them find the best unit for their specifications.
We also accept the custom, please contact us directly.
