| 摘要 |
PURPOSE:To suppress the generation of a high voltage induction ringing by connecting a choke coil whose resistive component satisfies a specific relation in series with a secondary winding. CONSTITUTION:The resistive component R of the choke coil 7 is decided to satisfy the relation of R<2>>4L/C, where L is the inductance of section widings 51-5n of the secondary winding 5 sectioned by diodes 61-6n and C is a line capacitance. The secondary winding is as shown in an equivalent circuit in figure, a secondary resonance by the inductance L and the line capacitance C of the secondary winding 5 is blocked and the generation of a high voltage induction ringing is suppressed. As the choke coil 7, a coil with a low Q aud having a large loss coefficient is suited to increase the resistive component R thereby increasing the core loss. That is, the impedance Z of the choke coil 7 is expressed as Z=R+jdivided by La, where La is the inductance and omega is the angular frequency, then the Q is obtained by Q=omegaLa/R. That is, the lower Q is better to increase the resistive component R for a increased core loss. |
