SU564717A1 - Converter of periodical time intervals into direct current - Google Patents

Description

one

The transform can be used, for example, the dp of forming the control current in the windings of the syp sensors of accelerometers and gyroscopes is proportional to a given periodic interval.

of time.

A known conversion of periodic time intervals into direct current, comprising a bridge circuit, in the arms of which there are keys; a load is included in one diagonal of the bridge; in the other, a power source, the time of the on state of the two opposite arms of the bridge being determined by the transformable interval 1.

A converter of periodic time intervals into direct current is also known, comprising a bridge circuit consisting of four keys, the control inputs of which are connected to the output of the control unit, for example a trigger, and a load 2 is included in one of the diagonals of the bridge circuit.

A disadvantage of the known devices is the leakage associated with unstable

by the nature of the delay in switching keys in a bridge circuit associated with the inertia of the keys and caused, for example, a change in the temperature of the external medium and {other determinative factors.

The circuit of the invention — an increase in the accuracy of the conversion — is achieved by the fact that in a known converter of periodic time intervals into a direct current comprising a trigger and a bridge circuit consisting of four keys, the control inputs of which are connected to the outputs of the trigger, a second bridge circuit with four keys is inserted iB is one of the diagonals of which the first bridge circuit is included, and the other is the power source, the second trigger, the outputs of which are connected to the control inputs of the keys of the second bridge. six elements coincide, the outputs of the first and second of them are connected to the first input of the first trigger, the outputs of the third and fourth to the second one of the first trigger, the outputs of the fifth and sixth, respectively, to the first and second inputs of the second grid gsra, a delay element connected between the first input of the converter and the first inputs of the first, fourth, fifth and sixth elements of the match, the third trigger, the first output of which is connected to the second inputs of the first, third and matching elements, and the second to the second input ladies; the second, fourth and sixth elements of the match and the frequency depot, inserted between the first input of the converter and the counting input of the third trigger, the second input of the converter connected to the first inputs of the second and third elements of the match. FIG. 1 shows a functional electrical circuit of the converter; FIG. 2 - time diagrams for his work. The outputs of the trigger 1 are connected to the control of the next inputs of the keys 2-5 of the first prototype circuit, one of the diagonals of which include the load. The power source 6 is included in one of the diagonals of the second bridge circuit on the keys 7-10, the diagonal of which includes the first bridge uenbt. The control inputs of the keys of the second bridge circuit are connected to the outputs of trigger 11. The inputs of the delay element 12 and the divider are connected to the first input of the converter. frequency 13, to the output of which the counting input of the trigger 14 is connected. To the first input of the trigger 1, the outputs of the matching elements 15 and 16 are connected to its second input - the outputs of the matching elements 17 and 18. The outputs of the trigger 11 are connected to the outputs of the joint Aden 19 and 2O. The first output of the trigger 14 is connected to the second inputs of the element match 15, 17, 19, and its second output to the second inputs of the elements match 16, 18,20. The second input of the converter is connected to the first inputs of matching elements 16, 17. The device operates as follows. The input pulses corresponding to the beginning of the convertible interval are sent to the First input of the converter (Fig. 2), and the pulses corresponding to its end are sent to the second input Bxj. After the delay element 12 (point O in Fig. 1 and 2) the interval between pulses is equal. De.: The frequency 13 frequency divides - the input pulse frequency (for the particular case shown in FIG. 2) into three. Let | trigger 14 is in a position where the point has a positive potential. At the same time, elements of coincidence 15, 17, 19 pulses, following in Bx, are prepared for OT1FYTY and open the element of coincidence 15 and the keys 2 11 5 (points 3 and g). and the impulse n Bhl open the coincidence 17 and the keys 4 and 3 (points e and h). Thus, there is a high-frequency switching of the current in the load with the frequency of the input pulses f ifTfj- Frequency divider 13 divides the frequency of the pulses by Bxj by AND 3 and, accordingly, trigger 14 is flung with this frequency. 17, 19 and the coincidence elements 16, 18, 20 open. The next one with a delay of t: Bx pulse. enters through the element of coincidence | l8 to the input: e of trigger 1, but since the trigger was already transferred before the impulse software ON Bxj through the element of coincidence 17, the trigger does not change its state. At the same time, trigger 11 is moved through the match element 2O (see graphs and, K in FIG. 2); the keys 8.9 are opened and the keys 7 and 10 are closed. Thus, the low-frequency switching of the current in the load occurs at a frequency equal to the frequency at the output of the splitter 13. There is no high-frequency switching at the specified time (see the graphs F, C and L, m in Fig. 2). After the flip-flop of the trigger 14, for the time ZT of the upper-frequency switching of keys 3,4, pulses are executed according to Bxj (via the coincidence element 18), and keys 2.5 - are executed by Bx (through the match epec of 1b). At the time of the next flip of the trigger 14, the coincidence elements 15, 17, 19 are reopened and the trigger 11 is again transferred. At the same time, keys 2 and 5 control the impulses B / through the coincidence element 15, and keys 3 and 4 the impulses Bx. j through match element 17, etc. Consider the case when a fault occurs, which implies a delay in the time for switching the keys relative to the trigger pulses by g1. At those moments when the keys 2 and 5 are controlled, an error occurs (see FIG. Mi 2 H) 1–2 At-error of the output current j-voltage, source 6; T is the load resistance. At the moment of controlling the pulses, respectively, E 2d. Thus, for. The period of PT switching error is compensated.

In the described transducer, the polarity of the power supply voltage of the first bridge circuit periodically changes, which makes it possible to mutually compensate for the errors caused by the instability of the switching delay for the two low-frequency switching periods, so that the average error for the low-frequency switching period is zero. In this case, switching the power supply of the first bridge circuit does not cause a change in the direction of the current in the load, since at the same time the phase of key management of the first bridge circuit changes. As a result, i increases the accuracy of the conversion.

Claims (2)

1.Konev Yu.I. Transistor Pulse Device Controls for Electric Motors and Electromagnetic Mechanisms, Energie, 1964. 2.Novitsky P.V. and others. Digital devices with frequency sensors, Energy p. 28O, fig. U- 40. 1