SU983574A1 - Digital average value phase meter - Google Patents

Description

(54) DIGITAL PHASE MEASUREMENT MEDIUM VALUE

The invention relates to an electrical measuring technique and can be used in information measuring systems for measuring the average value of phase shifts.

A digital mean phase meter is known for a value containing drivers, a four trigger and four elements AND ij.

The disadvantage of the phase meter is the complexity of the design, in particular, due to the use of four triggers and matching schemes.

The closest in technical essence to the proposed is a device containing drivers, the output of the first of which is connected to the counting input of the first trigger, the inverse output of which is connected to. one of the inputs, the first element And, the second trigger, the outputs of which are connected to the first inputs of the second and third elements And, the second inputs of which are connected to the output of the calibrator for measuring the average value of phase shifts, the third inputs to the output of the generator of counting pulses, and the outputs with inputs of addition and subtraction of a reversible counter, third trigger

and the fourth element And, and the output of the second driver is connected to the counting input of the third trigger, the direct output of which is connected to one of the inputs of the fourth element And, the other inputs of the first and fourth elements And are connected to the outputs; drivers, and outputs - from the input of the second trigger C2.

ten

The disadvantage of this phase meter is the complexity of the design, due, in particular, to the use of three triggers and four c) coincidence.

15

The aim of the invention is to simplify the design of the phase meter.

The goal is achieved by the fact that in the device, co-Gaming girls shapers, the output of the first of which is connected

20 to the counting input of the first trigger, the inverse output of which is connected to one of the inputs of the first element And, the second trigger, the outputs of which are connected to the first inputs of the second and

25 of the third And elements, the second inputs of which are connected with the output of the measurement time calibrator, the third inputs with the output of the calculator x generator, and the outputs with the inputs of the addition and subtraction of the reversible counter, the outputs of the first driver and the first element And are connected to the inputs of the second trigger, and the output of the second driver - to another input of the first element I.

Figure 1 shows the structural scheme of the device; figure 2 - temporary diagrams, illustrations of the general principle of operation.

The digital average phase meter contains a shaper 1, the output of which is connected to the counting input of trigger 2 and one of the inputs (S) of the trigger 3, a driver 4, the output of which is connected to one of the inputs of the element 5, the other input of which is connected to the inverse output trigger 2, and the output to another input (R) of trigger 3, and elements Ib and 7, one inputs of which are connected to the outputs of trigger 3, other inputs to the output of the calibrator measuring the average value of phase shifts, third inputs to the output of the counting pulse generator (not yet en), and outputs - to the inputs of the adding and subtracting the down counter 8 ..

The device works as follows.

The input signals 1% and U arrive at shapers 1 and 4, which at time points, the corresponding transition of said signals through a zero value in a certain direction, for example, from a negative to a positive region, form pulses (figure 2, a and b, respectively; for convenience and impliedness, all pulses are numbered). : The first impulse (1) from the output of shaper 1 sets the trigger 2 at the counting input to the position at which at its single output there is a high potential corresponding to a logic one (figure 2, c) and at zero it is a low one corresponding to a logical one (figure 2 , d) The same impulse sets trigger 3 to input S (FIG. 2, e), and element 6 transmits counting pulses which follow with frequency ω to the addition input (+) of the reversing counter 8 (figure 2, w if the resolving potential from the output of the calibrator time measurement Tp of the average value of phase shifts (Fig.2, i).

At the moment of time corresponding to the appearance of the first pulse (l) from the output of the imaging device 4 (element 5 is closed, since one of its inputs is connected to the inverse output of trigger 2, and at this output at a given moment in time there is a low potential close to zero ; figure 2, d), therefore, the specified pulse does not pass to the input R of the trigger 3.

The second impulse (2) from the output of the imaging device 1 throws the trigger 2 at the counting input to the initial position O, at which at its direct output - low potential (figure 2, c), and at the inverse - high (figure 2, g ), preparing element AND 5 for passing the second impulse (2) from the output of shaper 4. When this driver is triggered, the second impulse (2) from its output passes through element 5 (figure 2, d) to the input R of trigger 3 and throws the latter in the O position; at the direct output of the trigger 3 is now low potential (figure 2, e), and at the inverse is high, therefore the element And 7 passes the counting pulses following with frequency f to the input of the subtraction (-) reversible counter 8 (figure 2, u until the appearance of the third impulse (3) from the output of the former 1.

The following sequence of operations is similar to that discussed above.

The number of counting pulses accumulated in the meter during the measurement time

N kU27r4f) - (2ft: - / i),

where k is the number of averaged periods of input signals, the phase shift f between which is measured.

Thus, by introducing new connections, the proposed device provides the same result as the known one, while simultaneously simplifying the design of the phase meter (it has fewer triggers and coincidence circuits) and preserving all metrological characteristics.

Claims (2)

1.Glychenko A.S. and others. Digital methods for measuring the phase shift. M. Science, 1979, p. 231, fig. 7.4. 2. USSR author's certificate №473121, cl. G 01 R 25/00, 1975.