| 摘要 |
PURPOSE:To miniaturize and lighten a transformer by a method wherein high-frequency DC voltage applied to the primary winding of the transformer is modulated by low frequency, and a high-frequency component is removed from the output of secondary winding and converted into AC. CONSTITUTION:An emitter of a TR8 for modulation is connected to a base of a switching transistor (TR)9 and a pulse width control type high-frequency oscillator 6 and a low-frequency oscillator 7 are each connected to a collector and a base of the TR8. When voltage rectified is appied to a series circuit of the primary winding 10a of the transformer 10 and the TR9, voltage having a waveform shaped by modulating high-frequency oscillation pulses by low frequency is applied to the base of the TR9, boosted by means of the transformer 10 and outputted to the secondary winding 10b. The high-frequency component is removed by means of a diode 11 and a capacitor 12 from the output, a DC section is removed by means of a resistor 13 and a capacitor 14, low-frequency high voltage ACs are outputted while being detected by means of a current detector 15, the pulse width of the oscillator 6 is changed, and fixed output is obtained. Accordingly, the transformer 10 can be miniaturized and lightened in weight. |
