MEASURING TRANSDUCER FOR CURRENT AND VOLTAGE HARMONIC COMPONENTS Russian patent published in 1997 - IPC

FIELD: electric measurement technology. SUBSTANCE: voltage being measured is filtered off; clock pulses and measurement interval equal to fundamental period are shaped according to filtered-off signal by means of frequency multiplier 13, frequency divider 19, and write and reset pulse shapers 12 and 14, respectively; reference sine- and cosine-wave signals of same frequency as harmonic being measured are shaped by means of first and second functional transducers 6 and 7. Orthogonal components of current and voltage harmonics are measured in base of reference harmonic signals of respective frequency by digital integration of products of current and voltage derivatives by reference sine- and cosine-wave signal with aid of four reversing counters 30-33 whose content is re-entered at end of each measurement period in buffer registers 34-37 wherefrom it is entered in microcomputer 38. Current and voltage harmonics, phase shift angle between them, active, reactive, and total power are calculated by means of microcomputer. EFFECT: enlarged functional capabilities, improved accuracy in measuring fundamental component of current and voltage. 3 dwg