METHOD OF MEASURING VECTOR OF HARMONIC SIGNAL Russian patent published in 2012 - IPC G01R17/00 

FIELD: physics.

SUBSTANCE: method can be used in apparatus for measuring passive and active complex quantities, e.g., in bridges and alternating current compensators or in devices for measuring parameters of electrical circuits, as well as in vector voltmeter, by measuring the vector of a harmonic signal in case of several periodic interferences. Projections p' and p" of the measured signal S(t)=Asin(2πt/T+φ₀) on two orthogonal vectors of reference signals, associated with its amplitude A and the initial phase shift φ₀, are obtained via nonuniform sampling of the resultant signal and summation of its discrete values, sampling of which is carried out with instantaneous pulses acting at time instants which form, respectively for p' and p'', sets and where ΔT=(2r±1)T/4. r=0, 1, 2, …, which are formed step by step according to the condition where k_n = 1, 2, …, and is the number of the step matching the number of the interference signal P_n(t), such that and alternating-sign summation of discrete values σ(t) with coefficients a_i, wherein magnitude values of a_i are taken equal to one, and the signs are determined depending on the number of the discrete value according to the condition from the relationships: and where b_j=0.1 is the value of the j-th bit of the number of the sampling time of the i-th discrete value of the resultant signal (t), said number being presented in a binary number system, and is the number of the least significant bit, b_j, wherein k is defined as the number of the element b_j of the set {b₁}, where b₁=1, according to the condition k=inf1.

EFFECT: high accuracy of real-time measurement of the vector of a harmonic signal with a known period, acting together with periodic interference signals described by continuous functions, under the condition that their periods are also known and are not multiples of the period of the measured signal, and possibility of measuring useful harmonic signals from a number of interference signals.

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