SU139739A1 - Digital phase meter for measuring small phase shifts - Google Patents

Description

Phasometric devices are known that contain a phase shift transducer into a measured pulse of variable duration, a calibrated frequency pulse generator, and a key counting circuit. Also known phase meter device with a multiplication of the pulse duration. These devices have low resolution, which makes it impossible to measure with short accuracy short time intervals on the order of 1.

The proposed device differs from the known ones in that a three-winding transformer made on a magnetic core with a rectangular hysteresis loop is used as a multiplier for the duration of the measuring pulses. This allows the phase meter to be used not only for accurate measurements of small phase shifts between periodic signals (as indicated by the above-mentioned stroboscopic devices), but also for measuring phase shifts in non-repeating processes.

In this part of the proposal is new and useful.

FIG. 1 is a block diagram of the device, and FIG. 2 - diagrams of frequency multiplier.

The device contains two amplifiers 1 forming pulses at the time of passing the measured voltages through a zero value, a differential pulse forming unit 2, a reference voltage generator 3, a multiplier 4 measuring pulse duration, a key circuit 5, a time standard 6 and a counter 7.

The voltage, the phase difference between which it is necessary to measure, is applied to the shaping amplifiers /, the outputs of which are connected to the block 2 forming a "differential impulse, producing a pulse of constant amplitude. The duration of this pulse is determined by the length of time between the pulses from the output of the amplifiers /. . Coming from the output of the multiplier 4 positive momentum opens a key

circuit 5, which passes to the input of the counter 7 the corresponding number of pulses from the generator of the standard 6 time.

Y) the duration multiplier (Fig. 2) is a ferrite ring with a rectangular ring 8. a hysteresis loop on which three windings are wound: a signal 9, a remagnetization JO, and an output / Y. A differential pulse is applied to the winding 9, a constant-amplitude voltage surge smaller than the amplitude of the initial pulse is applied to the JO winding, and the time-multiplied pulse is removed from the winding //. The multiplication of the duration occurs due to the dependence of the magnetic reversal time of the core on the amplitude of the magnetization reversal pulse, the appropriate choice of which ensures the required multiplication factor.

PREDEME; the invention

A digital phase meter for measuring small phase shifts, containing a phase shift to proportional to shift shift, a measured pulse of variable duration, a calibrated frequency pulse generator and a key counting circuit, characterized in that it measures the phase shifts between non-repeating voltages A multiplier for the duration of the measured pulse, made on a magnetic core with a rectangular hysteresis loop and containing three windings: signal, reversing and output.

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