A PULSE GENERATOR FOR ELECTRIC FENCES

摘要

A circuit (700) for an electric fence energiser (examples are 6 or 24 Joule versions) which synthesises a pulse having a raised cosine waveform at a first or bus voltage uses a ferrite-cored output transformer (701) to multiply the voltage of the pulse to the required level. A raised cosine waveform has a low harmonic content and little filtering of high-power pulses is required in order to minimise electromagnetic emissions. On closure of a switch (707) in series with an inductor (705), a first capacitor bank (703) commences charging a second smaller capacitor bank (704) in parallel with the output primary, and after the peak of the pulse any remaining charge is dissipated in a resistor (708) with the aid of a saturable inductor (702), acting as a switch. The saturable inductor may be the output transformer itself for lower output energisers. The output exhibits little or any reversal of polarity when matched to its load. The circuit may also be useful for applications such as strobe flashers in aircraft.