LF static DC convertor - has auxiliary low power oscillator and varying width chopper circuit using sawtooth waveform

摘要

The static convertor providing a low frequency A.C. output from a D.C. supply using light transformers. The convertor utilises a pilot or auxiliary low power oscillator working at the required output frequency. This basic wave form is chopped by a sawtooth at a frequency of tens of kilohertz, whose pulse widths vary like the sinusoidal amplitude. The desired A.C. output is extracted from the chopped waveform. An output oscillator providing the basic low frequency waveform, feeds a series group of comparator/amplifiers and a detector which combine the input from a unijunction sawtooth generator to provide the chopping action.