METHOD FOR DIGITAL MEASUREMENT OF VOLTAGE OF ZERO SEQUENCE OF THREE-PHASE NETWORK

摘要

A method for digital measurement of voltage of zero sequence of three-phase network is based on analog-digital conversion and storage of codes of phase A, B, C voltages in the A-, B-, C- massifs of codes of phase instantaneous values, respectively, with obtaining through adding the codes of the A-, B-, C- massifs of codes of phase instantaneous values of the massif of codes of instantaneous values of voltage of measured symmetrical sequence of the main and higher harmonics. From the massif obtained through adding the codes of voltage of measured symmetrical sequence of each frequency separately are chosen. The number of measurements of the codes of phase instantaneous values is adjusted to the frequency fof network voltage and in each phase it is 3k (k=1, 2, 3, 4...). The codes of the i-th memory cells of the A-massif, B-massif and C-massif of codes of the phase instantaneous values are added, respectively, in sequence, beginning from the first memory cells for each massif of the codes of phase instantaneous values to obtain the massif of codes of instantaneous values of voltage of zero sequence.