RU2224261C1 - Procedure measuring complex impedance of bridge circuit with close inductive coupling and facility for its implementation - Google Patents

Abstract

FIELD: measurement technology. SUBSTANCE: invention refers to equipment giving signal when measured parameter achieves specified value. Procedure measuring complex impedance of bridge circuit with close inductive coupling consists in formation of signals in arms of bridge by action on them with signal of constant frequency, in comparison of values of signals formed in arms of bridge, in making judgment on relation of complex impedance by difference signal of arms. In contrast to prototype reference value of measured parameter is set, signals formed in arms of bridge circuit are shifted in phase through 90 degrees, phase of difference signal is measured, phase of difference signal is compared with phase of signal of constant frequency. Then moment of phase shift of difference signal through 180 degrees is recorded and this recorded moment is used to make judgment on equality of complex impedance. Facility measuring complex impedance of bridge circuit with close inductive coupling has generator of constant frequency connected to one diagonal of bridge circuit, amplifier connected to another diagonal of bridge circuit, adjustable amplifier and element of unbalance of bridge circuit with characteristic identical to arm resistance connected in series are connected in parallel with one of compared arms of bridge circuit. Output of amplifier is connected through filter and first amplitude comparator to first input of phase-sensitive recorder. Generator of constant frequency is connected to second input of phase-sensitive recorder which output is output of facility through phase shifter and second amplitude comparator connected in series. EFFECT: enhanced speed and accuracy of measurement of complex impedance of bridge circuit. 2 cl, 2 dwg

Description

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Claims (2)

1. A method of measuring the complex resistance of a bridge circuit with close inductive coupling, which consists in generating signals in the arms of the bridge circuit by applying a constant frequency signal to them, comparing the values of the signals formed in the arms of the bridge circuit, the difference signal of which judges the ratio of complex resistances, characterized in that set the reference value of the measured parameter, produce a phase shift of 90 ° of the signals generated in the shoulders of the bridge circuit, then measure the phase of the signal a difference produce a comparison phase difference signal with a constant frequency signal phase, whereupon the fixation of the time difference of the phase shift signal 180 ° and at a specified fixed point of equality judged complex impedances. 2. A device for measuring the complex resistance of a bridge circuit with close inductive coupling, comprising a constant frequency generator connected to one of the diagonals of the bridge circuit, an amplifier connected to another diagonal of the bridge circuit, characterized in that the adjustable amplifier and the unbalance element of the bridge circuit are connected in series with the characteristic identical to the shoulder resistance, connected in parallel to one of the compared shoulders of the bridge circuit, and the amplifier output through the filter and the first amplitude compara Op is connected to the first input of phase-sensitive lock, wherein the constant frequency generator through series-connected phase shifter and a second amplitude comparator is connected to the second input of the phase-sensitive latch, whose output is the output device.

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