SU415611A1 - - Google Patents

Description

one

The invention relates to the field of electrical measuring equipment, in particular to the field of phase measurements between two electrical voltages, used for phase meter calibration.

The well-known phase calibrator. Prirzy, contains a master oscillator with a set of dividers and a frequency multiplier, 1 connected in series, two identical channels, each of which is made of a series-connected circular phase shifter, Schmidt trigger, counting trigger, and counting circuit with a conversion factor, for example, 18, a low-pass filter, an output amplifier and an attenuator, as well as an additional phase shifter and a cathode-ray tube with horizontal and vertical amplifiers, the latter in turn connected with output clamps.

A disadvantage of the known calibrator is the low accuracy of the order of 0.1-0.2 ° and the impossibility of a fixed discrete setting of phase shifts, and therefore the calibration time is significant, since the setting of phase shifts is performed using a phase rotator and setting large angles close to 360 °, requires multiple rotations of the phase shift knob.

The aim of the invention is to increase the accuracy of the Phase Calibrators by about 0.01 -

0.02 ° due to a decrease in the time for setting the phase shift and automating the process of setting the phase shifts, as well as fixing the phase increments.

For this, the proposed calibrator is equipped with a sensor of a pair of pulses associated with a start button made of two Schmidt triggers, the inputs of which are connected via a switch to a master oscillator, and

two triggers connected to each other by closed outputs, the input of one of the triggers is connected to the start button, and the second key is connected to the output of one of the 111midt triggers, and the output of the second Schmidt trigger

through a differentiating circuit, a diode and a coincidence circuit is connected to the input of one of the mentioned counting triggers in the channel, while the inputs of Schmidt triggers in the said channels are connected to a circular phase rotator through a frequency divider with a factor of two.

FIG. 1 shows a block diagram of a proposed calibrator; in fig. 2 - work diagram.

The phase increment calibrator contains a master oscillator CG with a set of dividers and frequency multipliers UChh, connected in series, two identical channels, each of which is made of GF and VF, circularly connected phase shifter TCO, counting trigger CTi and CT2, and counting circuit nUi and PT with a conversion factor, for example, 18, low pass filter low pass filter and low pass filter, output amplifier VU | and BU And the attenuator AI and Az, as well as an additional phase shifter DF and a CRT tube with a vertical SVR and horizontal HGO amplifiers, the first is alternately connected via a switch Pz with output terminals Vi to Vz. The calibrator is equipped with a sensor for a pair of impulses DIP, connected with the start button K and made of two Schmidt triggers TShz TSh, 1, the inputs of which are connected via a non-switch FIi with a master oscillator SG, and two triggers Ti and TZ, connected with each other closed outputs, and its inputs - one TI-with the start button KN, and the other with the output of the Schmidt TShr trigger, and the output of the second Schmidt TSh4 trigger through differentiating DC DC, diode D and the SS coincidence circuit of the above mentioned counting Triggers in the channel, for example, ST ,, and in Odes of Schmidt Triggers TS and TS2 are connected to the GF and VF circular phase shifters through a DPhz frequency divider with a factor of two. The calibrator works as follows. Dividers DCH Д DCH and multiplier UCH, produce three signals with frequencies of, 72, 36 and 2.16 kHz. After DCH, signals with frequencies of 36, 18, and 1.08 kHz enter two channels, where the phase from them is divided (recalculated) 36 times. When phase shifters are 3–4 times, the output error will be 0.1–0.12 Pa. FIG. 2 shows the processes of pulse shift from the outputs of TSH1 and TCO: a) phase shifter shift less than 90 °; b) a shift of 180 °; c) a shift of 360 °. If in one channel the trigger state is changed (see Fig. 26, point y) and then returned again from point y to point x, then this will be equal to a shift of 360 °, and exactly for low frequencies, where trigger no delay Entering the two additional pulses of the moxphase at the output, but instantly moving the block, the DPI works as follows. The button K is pressed, the trigger TI is overturned and turns on the coincidence circuit CC, through which the double frequency pulses from TSH4 start to pass through DC and D to the input of CT Trigger T2, having calculated two pulses with TSHz, stops TI and from the coincidence circuit CC pulses on CTi they no longer pass, and the stationary mode is again restored there. The moment of the addition of two pulses to the sequence of pulses arriving at the input of CTi with TS (see Fig. 2d), as well as the change in the response of the trigger CTi from the initial (cm. Fig. 2e) is shown in Fig. 2e and fig. 2g. The subject of the invention is a phase increment calibrator containing a master oscillator with a set of dividers and a frequency multiplier, connected in series, two identical channels, each of which is made of a series-connected circular phase shifter, Schmidt trigger, counting trigger, conversion circuit with a conversion factor, for example, 18, filter of the lower frequencies, the output amplifier and the attenuator, as well as an additional phase shifter and a cathode ray tube with horizontal and vertical amplifiers, the latter alternately One is connected via a switch with output terminals, characterized in that, in order to increase accuracy and fix phase increments, it is equipped with a pulse pair sensor connected to a start button made of two Schmidt triggers, the inputs of which are connected via a switch to a master oscillator , and two triggers connected to each other by closed outputs, the input of one of the triggers connected to the start button, and the input of the other to the output of one of Schmidt's triggers, and the output of the second Schmidt trigger through a differentiating circuit, od and coincidence circuit is coupled to an input of one of said triggers counting channel. the inputs of the Schmidt triggers in these channels are connected to circular phase shifters through a frequency divider with a multiplicity of two.

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