PROCEDE ET DISPOSITIF POUR L'ELABORATION D'UN SIGNAL DE SYNCHRONISATION A PARTIR DES TENSIONS DE PHASE D'UN RESEAU

摘要

A microprocessor determines the zero cross-over times and direction of the phase voltages of the AC power line; a multiplexer has three parallel inputs which are respectively connected to the three phase conductors of the line and an output delivering a voltage formed by successive portions of the phase voltages; a flip-flop sensitive to the change of sign is connected to the output of the multiplexer; and EXCLUSIVE OR gate has an input connected to the output of the flip-flop and an other input to an output of the processor; and a NAND gate has an input connected to the output of the EXCLUSIVE OR gate and another input which receives a signal formed of a succession of square waves forming enabling windows.