CN112858771B - Distortion and pulsation signal testing method for airplane direct current 270V power supply system - Google Patents
Distortion and pulsation signal testing method for airplane direct current 270V power supply system Download PDFInfo
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- CN112858771B CN112858771B CN202110395160.0A CN202110395160A CN112858771B CN 112858771 B CN112858771 B CN 112858771B CN 202110395160 A CN202110395160 A CN 202110395160A CN 112858771 B CN112858771 B CN 112858771B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/005—Testing of electric installations on transport means
- G01R31/008—Testing of electric installations on transport means on air- or spacecraft, railway rolling stock or sea-going vessels
Abstract
The invention relates to a method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system, and belongs to the technical field of airplane power supply characteristic testing and calibration. The method is mainly used for accurately measuring the distortion and the pulsating signal of the airplane direct current 270V power supply system and tracing the distortion frequency spectrum and the pulsating voltage amplitude in the airplane direct current 270V power supply characteristic parameters to basic quantities. The invention subtracts the distortion and pulsation signals which are measured and superposed on the direct current 270V and the high-stability direct current 270V reference signal through a subtraction circuit which is formed by a high-voltage linear amplifier to obtain smaller distortion and pulsation signals; the signal satisfies the input range of an A/D converter with positive and negative signal measurements; meanwhile, the measured distortion and pulsation values are compensated and corrected by calibrating the amplitude-frequency characteristics of the high-stability direct-current reference signal and the subtraction circuit.
Description
Technical Field
The invention relates to a method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system, and belongs to the technical field of airplane power supply characteristic testing and calibration.
Background
The 270V DC power supply system of the airplane is the main power supply system of a new generation of fighters, and the existing 115V/400Hz AC power supply system is replaced to a great extent. The method is characterized in that: the brushless direct current generator has simple structure, reliable work and convenient parallel connection; the internal loss of the main power supply and the secondary power supply is small, and the efficiency is high; the reverse current protection diodes are connected in parallel, so that the power supply can not be interrupted due to the failure of a main power supply; the power grid has light weight; the harm ratio of 270V direct current to human bodies is smaller than that of 115V/400Hz alternating current; brushless starting power generation can be realized. Factors that cause distortion in the aircraft power supply system include the use of onboard generators, digital switching circuits, switching power supplies, and various rotating electrical machines. Factors that cause the ripple include regulation of the dc supply voltage, internal commutation or rectification of the dc supply, and load variations, among others. The quality of an airborne power supply is directly influenced by the sizes of distortion and pulse signals in an airplane power supply system, and the normal work of airborne electric equipment is greatly influenced. The existing airplane power supply characteristic testing device established for the 270V direct current power supply system lacks corresponding metering guarantee in the aspect of magnitude traceability, and particularly cannot effectively trace the source of distortion and pulsation signal parameters.
The dc distortion refers to an ac component contained in the dc voltage. The ratio of the DC distortion magnitude to the steady-state DC voltage is called the DC voltage distortion coefficient, and the square root mean value of each frequency component of the DC distortion is the distortion frequency spectrum. The distorted signal of the aircraft DC 270V power supply system is shown in FIG. 1. The essence is to superimpose several smaller ac signals on a 270V dc voltage. According to the relevant standard, the frequency range of the distorted signal is: 10Hz to 100kHz; the amplitude range is: 0.079V-3.162V. Ripple refers to the variation of instantaneous voltage around steady-state dc voltage during steady-state operation of the power supply system. The difference between the instantaneous voltage and the steady-state dc voltage is referred to as the ripple voltage amplitude. The pulsating voltage signal of the airplane direct current 270V power supply system is similar to a distortion signal, and is an alternating current small amplitude signal superposed on the 270V direct current voltage, and the frequency range is as follows: 1.2 kHz-16.8 kHz, the range of the pulse voltage amplitude is as follows: 0.24V-3.16V. Through the analysis, the main characteristic of the distortion and pulsation signal of the airplane direct current 270V power supply system is that a smaller alternating current signal (minimum to 0.079V) is superposed on a larger direct current signal (270V), and finally, the smaller alternating current signal needs to be directly measured (as shown in figure 1).
At present, distortion and pulsation signals of an airplane direct current 270V power supply system are measured by adopting a broadband voltage divider to attenuate unseparated direct current and alternating current signals at the same time, then a data acquisition system is adopted to measure the attenuated signals, and the obtained measurement data is subjected to alternating current and direct current separation in a mathematical calculation mode to further obtain values of the distortion and pulsation signals. Such a method usually uses a voltage divider with a large voltage division ratio (usually 40. Meanwhile, the bandwidth limitation of the voltage divider also has different degrees of influence on distortion and pulse signals, which causes larger errors to measurement results.
Disclosure of Invention
The invention aims to solve the problem of inaccurate measurement in the prior art and provides a method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system; the method is mainly used for accurately measuring distortion and pulse signals of the airplane direct current 270V power supply system and tracing the distortion frequency spectrum and the pulse voltage amplitude in the airplane direct current 270V power supply characteristic parameters to basic quantities. The method comprises the steps of subtracting a measured distortion and pulsation signal superposed on a direct current 270V from a high-stability direct current 270V reference signal through a subtraction circuit formed by a high-voltage linear amplifier to obtain a smaller distortion and pulsation signal; the signal shown satisfies the input range of an A/D converter with positive and negative signal measurements; meanwhile, the measured distortion and pulsation values are compensated and corrected by calibrating the amplitude-frequency characteristics of the high-stability direct-current reference signal and the subtraction circuit.
The purpose of the invention is realized by the following technical scheme.
A method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system comprises the following specific steps:
step one, a direct current high-stability reference signal source outputs a high-stability direct current reference signal;
and secondly, subtracting the direct current high-stability reference signal from the detected signal through a subtraction circuit to obtain distortion and pulse signals meeting the input range of the A/D converter. As shown in fig. 2;
step three, the A/D converter measures the values V of the distortion and pulsation signals n ；
Step four, calibrating the subtraction circuit by using standard 270V direct current distortion and pulse signals to obtain calibration data x n And compensating and correcting distortion and pulsation signal values through the calibration data.
The standard 270V DC distortion and pulsation signal V is measured by a subtraction circuit n Said signal V n Corresponding standard distortion and pulsation value x n N is a frequency point;
since the subtraction circuit uses a linear amplifier, the correction coefficient of the frequency point is:
by a correction factor k n Measuring the measured 270V direct current distortion and pulsation signal y obtained by the measurement in the step two n Performing compensation correction to obtain a corrected result U n Comprises the following steps:
U n ＝k n ×y n
and accurate measurement of distortion and pulse signals is realized.
The device for realizing the method comprises the following steps: the high-stability direct-current reference signal source, the subtraction circuit formed based on the high-voltage linear amplifier and the A/D converter. As shown in fig. 3.
The direct current high-stability reference signal source is used for generating a high-stability direct current reference signal and consists of a high-stability reference source and an independent high-voltage linear amplifier.
The subtraction circuit formed based on the high-voltage linear amplifier is used for subtracting a 270V direct-current power supply characteristic signal (including distortion and pulse signals) to be measured from a high-stability direct-current reference signal to obtain the distortion and pulse signals of the input range of the ADC meeting the measurement of positive and negative signals.
The A/D converter is used for measuring the values of the distortion and pulsation signals.
Advantageous effects
The method for testing the distortion and the pulsation signals of the airplane direct current 270V power supply system is used for accurately measuring the distortion and the pulsation signals of the airplane direct current 270V power supply system and ensuring the accuracy and the reliability of measured data. For airplane design and manufacturing departments, the method can be applied to an electric appliance parameter testing system of a power grid test bed, and the accuracy of the measurement of distortion and pulse signals of the testing system can be improved. For a test department, the method can be applied to an aircraft power grid quality monitoring system in a flight test, and real-time monitoring of distortion and pulse signals in the test flight process is guaranteed. For a metering department, the method can be applied to a power supply characteristic parameter calibration device, and the tracing problem of distortion and pulsation parameters can be solved.
Drawings
FIG. 1 illustrates the characteristics of 270V DC distortion, pulsation signals of an aircraft;
FIG. 2 shows the distortion and ripple signals obtained by the subtraction circuit;
FIG. 3 illustrates the principle of a 270V DC distortion and pulsation signal testing method for an aircraft;
fig. 4 shows the principle of the aircraft 270V dc distortion and pulsation signal test circuit.
Detailed Description
The invention is further described with reference to the following figures and examples.
Example 1
The 270V direct current power supply adaptability experimental equipment of the airborne product is an important testing device for evaluating the power supply quality of the airborne electric equipment adaptive to the airplane power supply. The main function of the simulation test device is to simulate the working state of the airplane power supply under various extreme conditions, so as to detect the capability of airborne electric equipment to adapt to the airplane power supply. The calibration device for the equipment needs to calibrate and trace the various analog power signals generated by the equipment, which involves accurately measuring 270V direct current distortion and pulsation signals contained in the signals.
As shown in fig. 4, the distortion and ripple measurement part of the calibration apparatus is composed of a highly stable dc reference signal source, a subtraction circuit, and an a/D converter.
The high-stability direct-current reference signal source consists of a voltage reference and a composite linear amplification circuit. Through the adjustment of the gain of the amplifier, the output high-stability direct current reference signal is 270V. The voltage reference is a high stability voltage reference source ADR4550 with a temperature characteristic of 2 ppm/DEG C. In the amplifier part, because the maximum input offset voltage of a PA94 chip is 5mV, and the temperature drift is 50 muV/DEG C, the measurement requirement cannot be met, an internal-external ring cascade system is formed by the ADA4522 and the PA94 by adopting a composite linear amplifying circuit, and the output error of the power amplifying part caused by the input offset and the temperature drift is reduced. The maximum steady-state precision error of the amplification channel due to the input offset voltage is 5 μ V × 2.5 × 14=0.175mv.
The subtracting circuit based on the high-voltage linear amplifier is composed of a high-voltage linear amplifier PA94, and the maximum allowable input voltage of the subtracting circuit is 350V. The 270V DC distortion and pulsation signal to be measured is added to the non-inverting input end of the amplifier through the voltage division circuit, and the 270V DC reference signal is fed back to the inverting input end through the resistor. When the four resistance values are the same, the output voltage of the amplifier is equal to 270V direct current distortion and pulsation signals to be measured minus 270V direct current reference signals, namely distortion and pulsation signals to be measured.
The A/D converter adopts a 16-bit ADC converter AD9656 based on an oversampling technology, the sampling rate of the ADC converter is 125MSPS, and the input voltage range of the A/D converter is enabled to be +/-10V through a pre-conditioning circuit.
A method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system comprises the following specific steps:
step one, a high-stability direct current reference signal source outputs a 270V direct current reference signal.
And step two, subtracting the 270V direct current distortion and pulsation signal to be detected from the 270V direct current reference signal by the subtraction circuit to obtain a smaller distortion and pulsation signal, wherein the voltage amplitude of the smaller distortion and pulsation signal is within the range of +/-10V.
And step three, the A/D converter performs digital-to-analog conversion on the distortion and pulsation signals obtained by the subtracter to obtain measured values of the distortion and pulsation signals.
And step four, calibrating the amplitude-frequency characteristic of the subtraction circuit by adopting standard 270V direct current distortion and pulse signals.
1) A sinusoidal signal with the amplitude of 1V is used as a standard distortion and pulsation standard signal, and the frequencies are respectively as follows: distorted signal frequency: 10Hz, 25Hz, 50Hz, 8230, 100k Hz. The signal is superimposed on a standard DC 270V signal to form a standard 270V DC distortion and pulsation signal.
2) And measuring the standard signal by using a subtraction circuit, and calculating the correction coefficient of each frequency point according to the measurement result.
3) And correcting and compensating the distortion and pulsation signal values measured in the step three according to the calculated correction coefficient.
The subtraction circuit was calibrated with a standard 270V dc distortion, ripple signal, with the results shown in the table below:
table 1: subtraction circuit calibration data table
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (2)
1. A method for testing distortion and pulsation signals of an airplane direct-current 270V power supply system is characterized by comprising the following steps: the method comprises the following specific steps:
step one, a direct current high-stability reference signal source outputs a direct current high-stability reference signal;
subtracting the direct current high-stability reference signal from the measured signal through a subtraction circuit to obtain distortion and pulse signals meeting the input range of the A/D converter;
step three, the A/D converter measures the values of distortion and pulsation signalsy n ；
Step four, calibrating the subtraction circuit by using standard 270V direct current distortion and pulse signals to obtain calibration datax n By said calibration datax n Compensating and correcting the values of the distortion and the pulsation signals;
measuring standard 270V DC distortion and pulsation signal by subtraction circuitV n Corresponding calibration datax n ，nIs a frequency point;
since the subtraction circuit uses a linear amplifier, the correction coefficient of the frequency point is:
k n ＝V n / x n ；
by correction factork n The measured 270V DC distortion and pulsation signal values obtained by the measurement in the third stepy n Performing compensation correction to obtain the corrected resultU n Comprises the following steps:
U n ＝k n ×y n ；
and accurate measurement of distortion and pulse signals is realized.
2. An apparatus for implementing the method of claim 1, wherein: the method comprises the following steps: the high-stability direct-current reference signal source, the subtraction circuit formed based on the high-voltage linear amplifier and the A/D converter are connected with the output end of the high-voltage linear amplifier;
the direct-current high-stability reference signal source is used for generating a direct-current high-stability reference signal and consists of a high-stability reference source and an independent high-voltage linear amplifier;
the subtraction circuit formed based on the high-voltage linear amplifier is used for subtracting a measured signal from a direct-current high-stability reference signal to obtain distortion and pulsation signals meeting the input range of an A/D converter with positive and negative signal measurement.
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| CN114039479A (en) * | 2021-11-12 | 2022-02-11 | 天津航空机电有限公司 | 270V direct current ground power supply voltage ripple protection circuit |
| CN116593757B (en) * | 2023-07-17 | 2023-11-03 | 济南巧步思仪器仪表有限公司 | Alternating current ratio measuring method, system and digital alternating current comparator |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201382997Y (en) * | 2009-02-11 | 2010-01-13 | 深圳市普禄科智能检测设备有限公司 | DC power detecting device |
| JP2012225798A (en) * | 2011-04-20 | 2012-11-15 | Nippon Denki Keiki Kenteisho | Oscillation device for ac measurement instrument testing power source |
| CN206387850U (en) * | 2016-11-28 | 2017-08-08 | 珠海格力电器股份有限公司 | A kind of ripple voltage detects circuit |
| CN108549039A (en) * | 2018-04-13 | 2018-09-18 | 同济大学 | A kind of Switching Power Supply ripple measuring circuit |
| CN109541311A (en) * | 2018-12-17 | 2019-03-29 | 西北工业大学 | Aviation conversion power supply system alternating voltage distortion parameter test system and its method |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201382997Y (en) * | 2009-02-11 | 2010-01-13 | 深圳市普禄科智能检测设备有限公司 | DC power detecting device |
| JP2012225798A (en) * | 2011-04-20 | 2012-11-15 | Nippon Denki Keiki Kenteisho | Oscillation device for ac measurement instrument testing power source |
| CN206387850U (en) * | 2016-11-28 | 2017-08-08 | 珠海格力电器股份有限公司 | A kind of ripple voltage detects circuit |
| CN108549039A (en) * | 2018-04-13 | 2018-09-18 | 同济大学 | A kind of Switching Power Supply ripple measuring circuit |
| CN109541311A (en) * | 2018-12-17 | 2019-03-29 | 西北工业大学 | Aviation conversion power supply system alternating voltage distortion parameter test system and its method |
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