Digital phasemeter with counting system - measures zero crossings of two signals to determine phase angle, storing result in memory

摘要

A phasemeter is described which comprises a digital counting system of two durations: one duration relating to the time between the zero crossing of a first periodic signal and the zero-crossing of a second periodic signal; and the second duration relating to the time between two zero crossings of one of the signals. A digital memory stores the result (T1) of the first duration and a second digital memory stores the result (T2) of the second duration. A digital value representing the quotient T1/T2 is then produced, this representing the angular phase shift between the two periodic signals.