SU759989A1 - Meter of integral parameters of periodic pulses - Google Patents

Description

The invention relates to electrical engineering and can be used in measuring systems with direct reading of measured values.

The closest to the present invention in its technical essence is a pulse parameter meter containing three integral pulse converters, three preamplifiers, a switch, an amplifier with an adjustable gain factor, a synchronization unit, a unit for measuring and indicating the duration of pulses, an analog pulse selector and a dial indicator {one].

A disadvantage of this device is low measurement accuracy.

In order to improve accuracy, the meter of integral parameters of periodic pulses, containing three integral pulse converters, the first inputs 20 of which are connected to the input of the meter, and the outputs are connected to the inputs of three preamplifiers, the output of the third preamplifier is connected to the input of the measurement and indication unit of the pulse duration, and the outputs of the first and 25 second preamplifiers to the fixed contacts of the switch, the output of which is connected to the amplifier input with adjustable gain, and the control input to the output of the block with nhronizatsii 30

2

the first input of which is connected to the output of the first integrated pulse converter, is equipped with an electronic key, an analog-digital converter, two digital-to-analog converters, a register, a code conversion and digital display unit, a reference level code source and a digital selection and switching unit, the first input of which is connected to the output analog-to-digital converter, the second input - with the output of the source code reference level, the first output - with the second input of the synchronization unit, the second output - with the input of the bl Formation of codes and digital indications, the third output is converted to the second digital-to-analog input, the fourth output to the register input, the output of which is connected to the input of the first digital-to-analog converter, the output connected to the control input of the amplifier with adjustable gain, and the output of the second digital-analog converter connected with the second input of the second integral pulse converter and the second input of the measuring and indicating unit of the pulse duration, and the input of the analog-digital converter the distributor is connected to the output of the electronic key, the input of which is connected to the output of the amplifier with adjustable

four

759989

I gain the gain, and the control input - with the output of the synchronization unit.

The structural electrical circuit of the device shown in the drawing.

The device consists of integrated pulse converters 1, 2, 3, preamps 4, 5, 6, an amplifier with adjustable gain 7, a unit for measuring and indicating the duration of pulses 8, a first digital-to-analog converter 9, a synchronization unit 10, an electronic switch 11, analog-digital converter 12, register 13, second digital-to-analog converter 14, digital selection and switching unit 15, code conversion and digital indication unit 16, switch 17 and reference level code source 18.

The device works as follows.

At the first stage of operation (when setting the gain), the expanded pulses from the output of the first integral converter 1 are fed through the switch 17, controlled by the synchronization unit 10, to the input of the amplifier 7 with an adjustable gain factor. Enhanced extended pulses using the key 11 controlled by the synchronization unit 10 and the memory element in the input circuit of the analog-digital converter 12 is converted into a quasi-constant voltage supplied to the converter 12. The output signal of the converter 12 in binary code is fed to the first input of the digital selection unit 15 and switching. In the first adder unit selection 15 is the difference of the codes of the signals from the transducer 12 and the source 18 code reference level. This difference is accumulated in the second adder with the register of the selection block 15, through the first multiplexer of the selection block 15 is transmitted to the register 13 and then converted by the first digital-to-analog converter 9 to a constant voltage, determining the gain of the amplifier 7. The gain is set until the codes on the outputs the converter 12 and the source 18 code of the reference level do not match, after which the signal from the first output of the selection unit 15 is fed to the second input of the synchronization unit 10, which translates the switch p 17 into second position. At the second stage of operation (when measured), the gain of the amplifier 7 does not change. Expanded pulses from the output of the second integrated converter are fed through switch 17, amplifier 7 and key 11 to the input circuit of converter 12, which converts the quasi-constant voltage into a binary code signal, which goes to the code conversion and digital display unit 16, where the magnitude of the generalized pulse amplitude is displayed . Simultaneously, from the third output of the selection unit 15, the signal of the converter 12 in binary code is fed to the input of the second converter 14, from the output of which the compensating direct voltage 1 / _k (established in steps) is fed to the nonlinear element of the second integral converter 2, shifting the operating point on the current-voltage characteristic such that the amplitude of the extended pulses decreases from the output of the second integral converter 2. The compensating voltage increases until the amplitude of the signal at the input of analog-to-digital converter 12 will not be equal (within the low-order digit of converter 12, which determines the comparison accuracy) to the amplitude of the reference voltage of source 18. Compensating voltage ύ'κ is used to measure the pulse duration, which is determined in block 8 of measurement and indication from ratios

/ and _caps

where (7 | _ШЗ - the amplitude of the pulses at the output of the third integral transducer 3.

The introduction of new units into the meter made it possible to significantly reduce the drift of memory devices, to increase the stability of the gain in the main path and the stability of the characteristics of the expander of the measured pulses.

The measurement error of the integral parameters decreased by 4-5 times as compared with the prototype, the adjustment of the meter was simplified.

Claims (3)

Claim Measuring instrument of integral parameters of periodic pulses, containing three integral pulse converters, the first inputs of which are connected to the input of the meter, and the outputs - to the inputs of three preamplifiers, the output of the third preamplifier is connected to the input of the measuring and indicating unit of pulse duration, and the outputs of the first and second preamplifiers - to fixed ones contacts of the switch, the output of which is connected to the input of the amplifier with adjustable gain, and the control input - with the output of the synchronization unit, the first input cat It is connected to the output of the first integral pulse converter, which is different in that it is equipped with an electronic key, an analog-to-digital converter, two digital-to-analog converters, a register, a code conversion unit and a digital display, a source code 759989 ' five the reference level and the digital selection and switching unit, the first input of which is connected to the output of the analog-digital converter, the second input - with the output of the source code of the reference level, the first output - with the second input of the synchronization unit, the second output - with the input of the code conversion unit and the digital display , the third output - with the input of the second digital-to-analog converter, the fourth output - with the input of the register, the output of which is connected to the input of the first digital-analog converter, the output connected to the control input will amplify A variable gain, wherein the output of the second digital to analog Preben the generator is connected to the second input of the second integral pulse converter and the second input of the measuring and indicating unit of the pulse duration, and The input of the analog-to-digital converter is connected to the output of the electronic switch, the input of which is connected to the output of the amplifier with adjustable gain and the control input to the output of the unit 10 sync.