Method of adjustment of the electrical power in three phase systems and related three phase static voltage regulator

Abstract From the Canadian patent

In a three phase static voltage regulator comprising a set of parallel-connected thyristor and diode between each phase R, S and T of a three phase supply source and the corresponding phase of a three phase load a pulse is produced in response to each single phase source voltage passing by a zero amplitude where the voltage amplitude changes from a negative to a positive value. A pulse is also produced in response to each such passage by a zero amplitude of the difference voltage between the phases R and S, which pulses are counted and digital-to-analog converted to produce a sawtooth signal of period To. During each period To, the sawtooth signal is compared with a reference signal to …