The Hv generator for 1000V from a 50 Hz mains supply, has its input transformer secondary coupled over a triac power switch to a HV multiplier cascade consisting of diodes and capacitors. The cascade HV output is divided and passed back to a comparator, where it is compared in amplitude with the output of a sawtooth generator. The sawtooth generator is synchronised with the supply frequency and that of the oscillator at twice the latter frequency, i.e. 100 Hz. The comparator output produces control pulses whose width depends upon the amplitude difference between the sawtooth and HV output waveforms. The control pulses are applied to the triac gate.
展开▼
