SU1195274A1 - Zero indicator of phase shift - Google Patents

Description

The invention relates to the field of phase-measuring technology and can be used in digital compensation phase meters. The purpose of the invention is to simplify the null indicator and increase its speed. Everything

the zero-indicator inputs are connected to the inputs of the first driver (Φ) 4 short pulses and F1 rectangular pulses. The output of the first F4 short pulses is connected to the K-input of the KZ-flip-flop, and the output of F1 rectangular pulses - to the first input of the first element I 5 directly, to the first input of the second element And 6 through an inverter 7. The second F2 short pulse is connected to the 5-input KZ-trigger 3. Direct and inverse outputs of the KZ-trigger connected to the second inputs of the first and second elements And 5 and 6, respectively. The third inputs of the elements And 5 and 6 are connected to the synchronization input of the zero-indicator, their outputs are connected to the inputs of the reversible counter 8. The outputs of the reversible counter are the outputs of the zero-indicator. 1 il.

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The invention relates to phase-measuring technology and can be used in digital compensation phase meters.

The purpose of the invention is to simplify the nullindicator and increase its speed. '

The drawing shows a structural diagram of the zero-phase shift indicator.

Zero — indicator contains shaper 1 square pulse, shaper 2 short pulses, short-circuit trigger 3, shaper 4 short pulses, elements 5 and 6, inverter 7, reversible counter 8, with inputs of the zero indicator connected to the inputs of the first shaper 4 short pulses and shaper '1 rectangular pulses,' the output of the first shaper 4 short pulses is connected to the K-input of the short-circuit trigger 3 ,. and the output of the rectangular pulse shaper 1 to the first input of the first element I 5 directly, to the first input of the second element 6 through the inverter 7. The second shaper 2 short pulses are connected to the 5-input of the short-circuit trigger 3, the direct and inverse outputs of which are connected with the second inputs of the first and second elements And 5 and 6, respectively, the third inputs of which are connected to the synchronization input of the null indicator, their outputs are connected to the inputs of the reversible counter 8, the outputs of the latter are the outputs of the null indicator.

The zero-indicator phase shift works as follows.

Shaper 1 provides the formation of pulses, the temporal position of the fronts of which corresponds to the moments of zero values of one of the input signals of the zero indicator.

At the output of shaper 2 short pulses are formed, the leading edge of which coincides with the trailing edge of positive pulses at the output of shaper 3. The pulses from the shaper 2 output go to the 3rd input of the trigger 3, while the short pulses from the shaper 4 output to the K input of the trigger 3 whose leading edge coincides with the moment of transition of the input voltage of the zero-through-to-pos. direction. At the exit Trig40

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Gera 3 rectangular pulses are formed, the duration of which depends on the phase angle of the input signals C and 11 ^. The signals from the direct output 5 of the trigger 3 are sent to the first input of the element And 5, and from the inverse to the first input of the element 6, while the second input of the element 5 gives signals from the output of the driver 1, and 10 to the second input of the element 6 the same signals are fed through the inverter 7, the third inputs of the elements 5 and 6 receive high-frequency pulses at the synchronization input of the null indicator. At (5 output one of the elements 5 and 6 (depending on the sign of the phase shift of the input signals C, and IR, high-frequency pulse packets are formed, and the number of pulses in the packet is proportional to the phase shift of the signals and. The specified pulse packets enter the summation or subtraction input reversible counter 8. At the moment when the reversible counter is perepol-

25 is fed along the summation input (subtraction), a pulse is generated at the output of the forward (reverse) transfer, which arrives at the corresponding output of the null indicator. In this case, the signal generation circuit for the initial code recording of the initial code that forms part of the reversing counter generates a pulse “establishing the initial code of the reversible counter, after which the cycle of operation 35 of the reversible counter repeats.

To the synchronization input zero-indicator20

torus, if used in

the digital compensation phase meter circuit, pulses are applied with the repetition rate £ from the driver

generator, part of the phase meter. This generator is a necessary part of a digital compensation phase meter tracking with a discretely controlled phase shift measure and serves to synchronize the phase shift measure, which operates at the same frequency £ _βχ as the zero indicator, and provides a phase shift control resolution of Δ4. In the case of using a null indicator in other devices, the synchronization input of the null indicator must be 55 sent from a separate generator, pulses with a frequency of £ _m , where l is the required resolution of the zero indicator.

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The average frequency of the pulses at the output of the null indicator is proportional to the current value of the phase angle of the input signals, and with a large value of this angle it can be. many times 5 to exceed the frequency of the input signals.

This ensures a high speed zero-indicator. When the phase shifts of the input signals are close to zero, the signals at the inputs of the reversible 10 counter 8 are either absent, or in packets of one or several pulses (in case of large fluctuations of the phase shifts of the input signals) come with equal probability of each of the inputs of the reversible counter 8, while there is no significant change in the initial code of the reversible counter and pulses at the outputs of the null indicator do not form 20. Thus, when the phase shift of the input signals is close to zero, high accuracy and noise immunity of the zero indicator are ensured.

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Claims (1)

Claim The zero indicator of the phase shift, containing the first shaper of short pulses, the shaper of the direct 30 coal impulses, inverter, K3thrigger, two elements AND, reversible counter, inputs of a null indicator connected to the inputs of the first shaper of short pulses and the former of rectangular pulses through the inverter, the outputs of the elements And are connected to the inputs of the reversible counter, characterized in that, in order to simplify the null indicator and increase its speed, a second form is inserted into it short pulse pulses, the output of the first short pulse shaper is connected to the K-input of the short-circuit trigger; accordingly, the third inputs of the elements And, are connected to the synchronization input of the null-indicator, the outputs of the reversible counter are connected to the outputs of the null indicator.