The working characteristics of induction coil
Induction is to use the principle of electromagnetic induction to work, when a current flows through a wire, the wire will be around the onset of certainelectromagnetic field, and the electromagnetic wire itself in the electromagnetic field scale wire attack induction effect. To attack attack electromagnetic wireitself effect, called "self" is the wire since episodes of changing the currentchange of magnetic field, the magnetic field is further affected the electric current in a wire; in attack other wires this electromagnetic field scale effect,called "mutual inductance". The high-frequency inductance coil resistance,electrical properties and capacitor instead, that is to say the high frequencysignal through the inductance coil will encounter great resistance, it is difficult to pass. Low pass, and the low-frequency signal after it is the resistance is small, i.e., low frequency signal can be simple through its inductance coilresistance on DC power is almost zero.
On the electrical signal in the circuit flow will appear a certain resistance, theresistance coil I call for the use of "impedance" inductance coil which appearson the current signal of the self inductance. The inductance coil and sometimes I call it the "inductive" or "coil", resistance. Letter L show. The winding inductance coil, the number of coils wound I usually call it the coilnumber of turns.
The measuring coil Q value method adopted is as follows:
(1) the selection of coil inductance coil with magnetic core with magnetic core,which can make the coil number and its resistance greatly cut, is conducive to the Q value of travel.
(2) according to the operation frequency selecting wire for winding coil. The inductance coil low-frequency operation should be selected with wire enameled wire insulating winding inductance coil. About the operating frequency in the tens of kHz to two MHz between, should choose multiple strands of insulatedwire, useful to add conductor cross-sectional area, cut the skin effect. The Q values up to 30% - 40%. The inductance coil on the operation frequency is higher than 2MHz, should choose single stranded thick wire winding, 0.3 - wirediameter is usually in the 1.5mm.
(3) reasonable selection of shield specification. Coil and shield, the loss will add coil, decrease of Q value. Therefore, shielding cover specification is not straight too big and too small in general, shield diameter and the coil diameter ratio should be 1 6-2.5, which can make the Q value decrease to less than 10%.
(4) selects the high quality skeleton cut dielectric loss. Usually on the inductance coil demand loss of small, high frequency of operation, should choose high-frequency Tao Shu, poly prison fluoride, polystyrene and otherhigh frequency dielectric material as the skeleton. The inductance coil on theultra high frequency operation, available without skeleton method of winding.
For details please visit our official website: http://www.www.wangchenyu.net.cn
Source: http://www.www.wangchenyu.net.cn (reproduced please specify the reproduced source)
