FIELD: electric measurement technology. SUBSTANCE: all phase currents are sequentially time-integrated within half-cycle of modulating voltage whose frequency is three-fold that of current being measured, that is, within space T/6, where T is period of current under measurement. Measurement time and yield of results make up one sixth of period and all phase currents are measured by means of one channel. EFFECT: improved speed and facilitated procedure. 2 dwg
