Polyphase mains-operated converter compensating for frequency changes - has sawtooth generators with integrators charged to same amplitude (NL 20.5.80)

摘要

A polyphase mains-operated converter has a triggering circuit which operates on the vertical control principle. It obviates the need of special circuits to compensate for the tolerances in the components and there frequency changes. The output voltage of each phase of a synchronising sawtooth generator is compared with a control voltage in a comparator. The integrators of the sawtooth generators are charged to the same peak value in the interval between two consecutive zero points of the control a.c. voltage. The latter is synchronised to the mains. The control circuit consists of a reference voltage source, a reversal amplifier an averaging circuit and a regulator.