SU1037189A1 - Bridge-type measuring device - Google Patents

Abstract

1. A BRIDGE MEASURING DEVICE containing a start-up impulse generator, a supply impulse generator connected in series, a balanced pavement measuring circuit, a zero-organ whose second input connected to the output of the gating element, and an equilibrium indicator that, in order to improve noise immunity, short-term interference, repeated with a certain or chaotic frequency of the following, it is equipped with a pause maker, a normalizer and a pulse code selector, and the pause generator is connected between the output of the start pulse generator and the combined inputs of the generator of supply pulses and the gating element, and the serially connected normalizer and the selector of the pulse code are connected between the output of the zero-organ and the indicator / L equilibrium input. t

Description

2. The device according to claim 1, characterized in that the gap generator contains three series-connected delay elements and an OR element, and the outputs of the delay elements, as well as the output of the pulse generator, are triggered to the inputs of the OR element — the output of the OR element is an output the pause generator and the input of the first delay element is the input of the pause generator.

3. Device POP.1 / DIFFERENT THAT the selector

the pulse code contains four serially connected delay elements, the amplitude adder and the amplitude discriminator, the outputs of the delay elements are connected to the corresponding inputs of the amplitude adder, the fifth input of the amplitude adder and the input of the first delay element are the input of the pulse code selector, and the output of the amplitude discriminator is the output pulse code selector.

The invention relates to a measurement technique and is intended to measure multi-element two-terminal parameters by means of bridge measurement circuits on a pulsed power supply under conditions of short-term interference comparable in duration to the duration of the bridge-supplying pulses and repeated with a specific or random tracking frequency. complex impedances containing a generator of short starting pulses with a reference and delayed signal output Delay block Matora sum generators long and short rectangular pulse voltage measuring bridge circuit to the differential input of the oscilloscope. The measured parameters in the circuit are the two active and capacitive parameters of the three-element two-terminal LlJ. A disadvantage of this device is that it does not provide noise immunity. The closest in technical essence to the invention is a device comprising a trigger pulse generator, a power pulse generator connected in series, a balanced pavement measuring circuit, a null organ, the second input of which is connected to the output of the gating element, and the equilibrium indicator G2}. A disadvantage of the known device is low noise immunity. The purpose of the invention is to increase the noise immunity in the presence of short-term noise repeated at a certain or random tracking frequency. The goal is achieved by the fact that a bridge measuring device comprising a pulse generator. start-up, a supply pulse generator connected in series, a balanced pavement measuring circuit, a zero-body, the second input of which is connected to the output of the gating element, and an equilibrium indicator, is equipped with a pause generator, a normalizer and a pulse code selector, the pause generator is connected between the trigger pulse generator output and the combined inputs of the generator of supply pulses and the gate element, and the serially connected normalizer and pulse code selector are included Between the output of the null organ and the input of the equilibrium indicator. In this case, the gap generator contains three series-connected delay elements and an OR element, and the outputs of the delay elements, as well as the output of the start-up pulse generator, are connected to the inputs of the OR element, the output of the OR element is form-output. The pause selector and the input of the first delay element are the input of the form B ate pause. In addition, the pulse code selector contains four series-connected delay elements, an amplitude adder and an amplitude discriminator, the outputs of the delay elements connected to the corresponding inputs of the amplitude adder, the fifth input of the amplitude adder and the input of the first delay element are the input of the pulse code selector, and amplitude output. A dial-1-inator is the output of a pulse code selector. FIG. 1 shows a functional electrical circuit of a bridge measuring device; Fig. 2, according to his work.

The MocTdBoe measuring device contains a generator of 1 start pulse, a shaper of 2 pauses between bridge feeding pulses, consisting of delay elements 3-5 and a four-input element OR b, generator 7 of feeding pulses, gating element 8, balanced bridge measuring circuit 9, zero-body 10 , the normalizer 11, the pulse code selector 12, which contains delay elements 13-16, amplitude adder 17 and amplitude discriminator 18, indicator 19 equilibrium. FIG. 2 shows a diagram, where 20 is the clock pulse of the generator 1 start pulse; 21 - pulse sequence at the output of the shaper 2 pauses; 22-25 are the pulse sequences coming from the outputs of the delay elements 43-16, respectively; 26 output pulses of the amplitude adder 17.

Bridge measuring device operates as follows.

The start-up pulse generator 1 synchronizes the operation of the device by the time of transition of the network frequency after 0. Clock pulses (20) with a repetition period T, coming from the output of the trigger pulse generator 1 to the input of the pausing generator 2, are successively delayed in delay elements 3-5 for periods of time t - TK, respectively, Which do not. Be multiple to each other. Clock and output pulses of elements 3-5 of the delay arrive at the input of the element YAL I 6, forming at its output a sequence of 21 pulse signals with irregular pauses, ta / f b, T - (Ti + tTi) between the pulses, controlling the generator 7 supplying the bridge circuit of the PULSE and the gating element 8 operating in the standby mode. The gating element 8 extracts from the imbalance signal of the 1.speed measuring circuit 9 sections that carry information about the state of the bridge circuit 9 according to the corresponding measured parameter. If the bridge circuit 9 is in equilibrium state, the signal at the output of the zero-organ -10 is absent, therefore there is no signal at its output, correspondingly there are no signals at the output of the normalizer 11 and the selector 12 of the pulse code, and the equilibrium state of the measuring bridge scheme 9 will be fixed by indicator 19 equilibrium. If the bridge circuit 9 is unbalanced, a signal is output at the output of the null organ 10, the amplitude of which depends on the degree of mismatch of the measuring bridge junction 9. The pulse signal reduced to a standard value by the normalizer 11 is fed to the input of the pulse code selector 12, is successively delayed delay elements 13-16 on segments T (TGa + Tb, G%, Ta, T, respectively, the output signals of which are and

the input signal from the normalizer 11 goes directly to the corresponding inputs of the amplitude adder 17, the output impulse 26 of which through the amplitude discriminator 18 enters the equilibrium indicator 19. The transmission level of the amplitude discriminator 18 is chosen so that the operation of the equilibrium indicator 19 is possible only if the inputs of the amplitude adder 17 is simultaneously present for at least three pulses. Upon receipt at the input of the selector 12 of the pulse code pulses psmieh with chaotic or

a certain frequency of operation and {equilibrium of the equilibrium 19 is possible in the case of coincidence of the intervals between interference pulses with a delay time of at least

than in the three delay elements 15 and 16, which is less likely.

Thus, the bridge measuring device allows the selection of pulses carrying

information about the state of the measuring bridge circuit against the background of a random stream of short-term interference repeated with a specific or chaotic tracking frequency, the duration of which is much shorter or comparable to the duration of the pulse of the pulse signal bridge, but not more than the tracking period, which allows measurements of the parameters of multi-element two-pole at

shop conditions with a high level. high frequency interference as well. complex with equipment having a high level of its own high-frequency interference while maintaining the high metrological characteristics inherent in bridge measuring devices on a pulsed power supply.

Fig 2

Claims (3)

1. A BRIDGE MEASURING DEVICE comprising a trigger pulse generator, serially connected supply pulse generator, a balanced bridge measuring circuit, a zero-organ, the second input of which is connected to the output of the strobe element, and an equilibrium indicator, characterized in that, in order to increase the noise immunity at the presence of short-term interference, repeating with a certain or chaotic repetition rate, it is equipped with a pause former, a normalizer and a pulse code selector, and A pause generator is connected between the output of the trigger pulse generator and the combined inputs of the supply pulse generator and the gating element, and the normalizer and the pulse code selector are connected in series between the zero-organ and the input of the equilibrium indicator. SU, .. 103718 Figure 1 CO> 2. The device according to claim 1, characterized in that the pause driver contains three series-connected delay elements and an OR element, and the outputs of the delay elements, as well as the output of the pulse generator, trigger are connected to the inputs of the OR element, the output of the OR element is the output of the pause driver , and the input of the first delay element is the input of the pause former. 3. The device pop. 1, with the proviso that the pulse code selector contains four series-connected delay elements, an amplitude adder and an amplitude discriminator, and the outputs of the delay elements are connected to the corresponding inputs of the amplitude adder, fifth the input of the amplitude adder and the input of the first delay element are the input of the pulse code selector, and the output of the amplitude discriminator is the output of the pulse code selector. 1 ¹ ,