High voltage generator using rapid response boost / flyback converters for stun gun applications

Abstract

This paper presents high voltage generator for stun gun applications. The proposed high voltage generator consists of coupled-inductor boost and flyback converters, which adopts active clamp circuit to recover energy trapped in leakage inductances of coupled inductor and transformer in two converters simultaneously. With this approach, coupled-inductor boost converter can boost voltage of battery up to a high output voltage, while flyback converter is adopted to step up the output voltage up to the desired voltage of capacitated paralysis for convicts conferring. In order to increase safety of the stun gun, transformer of flyback with a high turns ratio is used by multi-winding method in secondary winding to speed up output response and to reduce charges supplied by stun gun for meeting maximum enduring charges of human body. Since switches in the proposed generator adopts switch integration technique, its weight and volume can be reduced and its conversion efficiency can be increased. As compared with conventional stun gun, the proposed one can achieve 210 ten-second firings which exceeds 1.5 times of ten-second firings of the conventional one. Finally, a prototype under maximum output voltage of 30kV and maximum output current of 5mA has been implemented to verify feasibility of the proposed high voltage generator.