RU2364881C1 - Device for calibration of measuring converter - Google Patents

Abstract

FIELD: physics, measurement.

SUBSTANCE: invention is related to metrology, namely to facilities for adjustment and calibration, and may be used for calibration of measuring converters. In order to achieve technical result, device comprises generator of signals, measuring converter, generator of radio pulses, power dividers, frequency metre, power amplifier, digital wattmetre, computer and two power supply units.

EFFECT: expansion of functional resources.

2 cl, 1 dwg

Description

The invention relates to metrology, and in particular to means of verification and calibration, and can be used to verify the measuring transducers of the average power level of a radio pulse signal to a constant voltage level.

A device for checking functional measuring transducers (AS USSR No. 1622863, publ. 23.01.91), containing a voltage calibrator, a comparison unit, a registration unit, input and output terminals for connecting a verifiable functional measuring transducer. To increase the reliability of the verification results, a temperature meter, a subtraction unit, and a computational-logical unit are introduced into the device.

A device is known that implements a method for monitoring the metrological characteristics of measuring transducers (AS USSR No. 1239663, publ. 23.06.86), comprising a control unit, a reversible counter, a digital-to-analog converter, valves, a generator, a divider, a measuring converter and four buses.

A device is known that implements a verification method for measuring instruments (AS USSR No. 1290218, publ. 15.02.87) containing a controlled key element, a comparison unit and a verified device.

A device is known that implements a method for determining the frequency errors of scale converters (AS USSR No. 1370591, publ. 30.01.88), comprising a reference frequency generator, a tunable controlled frequency generator, variable attenuators, an exemplary voltage divider, automatic switches, an investigated scale converter, balanced modulator, broadband amplifier, amplitude detector, switching frequency amplifier, synchronous detector, switching frequency generator and indicator.

There is also a device for calibrating a measuring transducer using the model instrument for calibrating primary measuring transducers (“Metrological support and operation of measuring equipment.” / Ed. By Kuznetsov VA M: Radio and communications, 1990, p. 97, Fig. 8.8) comprising a signal generator, a measuring transducer, a first exemplary measuring instrument and a second exemplary measuring instrument. The specified device is the closest analogue (prototype) of the claimed invention.

A common disadvantage of these devices is the inability to verify the measuring transducers of the average power level of the radio pulse signal to a constant voltage level.

The task to which the invention is directed is to expand the arsenal of technical means of the indicated purpose, namely, to create a device for checking measuring transducers of the average power level of a radio pulse signal to a constant voltage level.

The technical result in the implementation of the invention, in particular, is the ability to verify the measuring transducers of the average power level of the radio pulse signal to a constant voltage level both during their production and during operation; automation of the verification procedure of these measuring transducers; improving the accuracy of measuring the parameters of the conversion characteristics; increasing the completeness of calibration of measuring transducers (increasing the number and range of parameters to be verified).

To achieve the indicated technical result, a radio pulse generator, a first power divider, a frequency meter, a power amplifier, a second power divider, a digital wattmeter are introduced instead of the first model measuring instrument and the second model measuring instrument into a device for calibrating a measuring transducer using a reference instrument containing a signal generator and a measuring transducer. , a computer, a first power supply unit consisting of a first power module, a first digital voltmeter and a first digital second milliammeter, a second power supply unit consisting of a second power module, a second digital voltmeter and a second digital milliammeter, and a third digital voltmeter, the output of the signal generator being connected to the input of the radio pulse generator, the output of the radio pulse generator connected to the input of the first power divider, the first output of the first divider power is connected to the frequency meter, the second output of the first power divider is connected to the input of the power amplifier, the output of the power amplifier is connected to the input of the second power divider and, the first output of the second power divider is connected to the first input of the measuring transducer, the second output of the second power divider is connected to the input of the digital wattmeter, the output of the digital wattmeter is connected to a computer, the output of the first power module is connected to the input of the first digital voltmeter and the input of the first digital milliammeter, the output of the first the digital milliammeter is connected to the second input of the measuring transducer, the output of the second power module is connected to the input of the second digital voltmeter and the input of the second digital milliammeter output of the second digital milliammeter connected to the third input of the transmitter, the transmitter output is connected to the third input of digital voltmeter DVM third output connected to the computer. The first and second power dividers are double-arm and symmetrical with a power transmission coefficient of 0.5 in each arm.

The main parameter of the measuring transducer is its characteristic of converting the average power level of the radio pulse signal to the constant voltage level, expressed by the equation u = A × P + B, where P is the average power of the radio pulse signal measured at the input of the measuring transducer; U is the DC voltage level measured at the output of the measuring transducer; A and B are constant coefficients. In the process of calibration of the measuring transducer, the values of the coefficients A and B are determined, as well as the standard deviation S _{p of} measuring these coefficients.

The drawing shows a structural diagram of a calibration device measuring transducer.

The calibration device of the measuring transducer comprises a signal generator 1; generator 2 radio pulses; first power divider 3; frequency counter 4; power amplifier 5; a second power divider 6; a measuring transducer 7 of the average power level of the radio pulse signal to a constant voltage level; digital wattmeter 8; computer 9; a first power supply unit 10, consisting of a first power supply module 11, a first digital voltmeter 12 and a first digital milliammeter 13; a second power supply unit 14, consisting of a second power module 15, a second digital voltmeter 16 and a second digital milliammeter 17; the third digital voltmeter 18. The output of the signal generator 1 is connected to the input of the generator 2 radio pulses, the output of the generator 2 radio pulses is connected to the input of the first power divider 3, the first output of the first power divider 3 is connected to the frequency counter 4, the second output of the first power divider 3 is connected to the input of amplifier 5 power, the output of the power amplifier 5 is connected to the input of the second power divider 6, the first output of the second power divider 6 is connected to the first input of the measuring transducer 7 of the average pulse power about the signal to the DC voltage level, the second output of the second power divider 6 is connected to the input of the digital power meter 8, the output of the digital power meter 8 is connected to the computer 9. The first power supply unit 10 consists of a first power supply module 11, a first digital voltmeter 12 and a first digital milliammeter 13, moreover, the output of the first power module 11 is connected to the input of the first digital voltmeter 12 and to the input of the first digital milliammeter 13, and the output of the first digital milliammeter 13 is connected to the second input of the measuring transducer 7 levels of average power of a radio pulse signal to a constant voltage level. The second power supply unit 14 consists of a second power module 15, a second digital voltmeter 16 and a second digital milliammeter 17, the output of the second power module 15 being connected to the input of the second digital voltmeter 16 and to the input of the second digital milliammeter 17, and the output of the second digital milliammeter 17 connected to the third input of the measuring transducer 7 of the average power level of the radio pulse signal to the DC voltage level. The output of the measuring transducer 7 of the average power level of the radio pulse signal to the DC voltage level is connected to the input of the third digital voltmeter 18, and the output of the third digital voltmeter 18 is connected to the computer 9.

The calibration device of the measuring transducer operates as follows. The signal generator 1 generates video pulse signals that are supplied to the radio pulse generator 2. The generator 2 radio pulses using video pulses modulates a continuous radio signal and generates a radio pulse signal. The modulated radio pulse signal is supplied to the first power divider 3. From the first power divider 3 power 0,5P ₂ radio signals

(P ₂ is the power of the radio signal from the generator 2 radio pulses) is supplied to the frequency counter 4, which measures the frequency of the filling of the radio pulse, and 0.5 R _{2 of the} radio signal is supplied to the power amplifier 5. The power amplifier 5 amplifies the power of the radio signal and transfers it to the second power divider 6. From the second power divider 6, the power of the 0.5P ₅ radio signal (P ₅ is the power of the radio signal from the power amplifier 5) is supplied to the measuring transducer 7, and the 0.5P ₅ radio signal is supplied to the digital wattmeter 8. Using the digital wattmeter 8, the average level of the radio signal power is measured , which is equal to the value of the average power level of the radio signal at the first input of the measuring transducer 7, and the measured value is transmitted to the computer 9. At the first power supply unit 10 and the second power supply unit 14 using the first digital oltmetra 12 and digital voltmeter 16 of the second set value of the supply voltage E ₁ and E ₂ is input to the transmitter 7. Then use contained in the first block 10 and the second power supply unit 14 first digital milliammeter 13 and second digital milliammeter 17 measured values of the currents I _{and 1} and I _{and 2} , arriving at the measuring transducer 7, respectively, along the voltage circuits E ₁ and E ₂ . The measured values of currents I _{and 1} and I _{and 2} are entered into the computer 9. In addition, the values of the modules of permissible deviations are preliminarily entered into the computer 9

| ΔI _p1 | and | ΔI _n2 |. All values can be entered into computer 9 by the operator. Computer 9 for a given program performs the following calculations:

- calculates the deviations | ΔI _{and 1} | and | ΔI _{and 2} | measured currents I _{and 1} and I _{and 2} of the rated values of I _n1 and I _n2, respectively, by the formulas:

- carries out verification of the implementation of the relations:

If at least one of the relations (3) or (4) is not satisfied, then the measuring transducer 7 is rejected and given for repair. If both ratios (3) and (4) are satisfied simultaneously, then the calibration of the transmitter continues.

Using the generator 2 radio pulses at the input of the measuring transducer 7 sets the average power value P _n from the set of powers P _n , where n = 1, 2, ..., N. Digital wattmeter 8 measures the average power of the radio signal P _n , where n = 1, 2 , ..., N, which is equal to the average power at N points at the first input of the measuring transducer 7. The measured values are sent to computer 9. The third digital voltmeter 18 measures the value of the constant voltage U _n , where n = 1, 2, ..., N, in the same points N at the output of the measuring transducer 7. Measure These values are sent to computer 9. In addition, the value of the permissible mean square error S _p . Computer 9 for a given program performs the following calculations:

- calculates the values of the coefficients A and B by linear regression;

- calculates the standard error of S _and measuring the coefficients A and B;

- carries out verification of compliance

If relation (5) is not satisfied, then the measuring transducer 7 is rejected and given for repair. If the ratio (5) is fulfilled, then the measuring transducer 7 is recognized as fit for use.

The resulting information is displayed as a protocol of verification results, which indicates:

- the values of the measured currents I _{and 1} and I _{and 2} ;

- the values of permissible | ΔI _p1 |, | ΔI _p2 | and calculated | ΔI _{and 1} |, | ΔI _{and 2} | deviations of the measured currents of power supply units 10 and 14;

- values of the coefficients A and B;

- the values of permissible S _p and calculated S _and standard errors of the measurement results of the coefficients A and B.

According to the results of verification, a decision is made to reject or recognize the measuring transducer as usable.

Claims (2)

1. The calibration device of the measuring transducer, comprising a signal generator and a measuring transducer, characterized in that it contains a radio pulse generator, a first power divider, a frequency meter, a power amplifier, a second power divider, a digital wattmeter, a computer, a first power supply unit consisting of a first power supply module, a first digital voltmeter and a first digital milliammeter, a second power supply unit consisting of a second power module, a second digital voltmeter and a second digital milliammeter, and t a third digital voltmeter, wherein the output of the signal generator is connected to the input of the radio pulse generator, the output of the radio pulse generator is connected to the input of the first power divider, the first output of the first power divider is connected to the frequency meter, the second output of the first power divider is connected to the input of the power amplifier, the output of the power amplifier is connected to the input the second power divider, the first output of the second power divider is connected to the first input of the measuring transducer, the second output of the second power divider is connected with the input of the digital wattmeter, the output of the digital wattmeter is connected to the computer, the output of the first power module is connected to the input of the first digital voltmeter and the input of the first digital milliammeter, the output of the first digital milliammeter is connected to the second input of the measuring transducer, the output of the second power module is connected to the input of the second digital voltmeter and the input of the second digital milliammeter, the output of the second digital milliammeter is connected to the third input of the measuring transducer, the output is a converter coupled to the input of the third digital voltmeter DVM third output coupled to an input of the computer. 2. The calibration device of the measuring transducer according to claim 1, characterized in that the power dividers are double-arm and symmetrical.

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