PULSE POWER SOURCE FOR FLUORESCENT LAMPS WITH COLD CATHODE Russian patent published in 2006 - IPC H05B41/30 H02M7/53 

FIELD: engineering of secondary power sources, possible use for engineering transformers of direct voltage to high-power alternating voltage of given frequency, in particular, for powering fluorescent lamps with cold cathode.

SUBSTANCE: device of fluorescent lamps power source has first semiconductor key, having first output, second output and controlling output, while first output is connected to output of ground of pulse power source, transformer, having primary winding with primary inductiveness, connected serially to first semiconductor key so, that its first end is connected to second output of first semiconductor key, and second end is connected to output of primary power source, powering pulse power source, and secondary winding, having number of coils at least ten times exceeding number of coils of primary winding, decoupling capacitor having first output, connected to first end of secondary transformer winding and connected serially with secondary winding of transformer, which by its second end is connected to first output of lamp, and second output of lamp is connected to second output of decoupling capacitor, second semiconductor key, having first, second and controlling outputs, and accumulating capacitor serially connected to the former on the side of first output, second output of accumulating capacitor is connected to second output of first key and to first end of primary transformer winding, controlling circuit, having first output, connected to controlling output of first semiconductor key, second output, connected to controlling output of second semiconductor key, and processing signals in a way to firstly enable first semiconductor key within limits of cycle, while second one is disabled, and then do the same vice versa, while controlling circuit enables and disables aforementioned keys with frequency, exceeding resonance frequency of circuit, consisting of primary inductiveness of transformer and capacitance of accumulating capacitor, second output of second semiconductor key is connected to output of primary power source. Second semiconductor key is connected to ground of pulse power source. Controlling circuit includes decoupling capacitor, serially connected to controlling output of second key, resistor, connected by its first output to controlling output of second key, and by its second output to ground of pulse power source, and a semiconductor diode, connected by its cathode to ground, and by its anode - to controlling output of second key.

EFFECT: decreased current oscillations in primary voltage source.

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