CN112798084B - Standard meter method gas flow testing device and variable frequency adjustment control algorithm thereof - Google Patents
Standard meter method gas flow testing device and variable frequency adjustment control algorithm thereof Download PDFInfo
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- CN112798084B CN112798084B CN202110162542.9A CN202110162542A CN112798084B CN 112798084 B CN112798084 B CN 112798084B CN 202110162542 A CN202110162542 A CN 202110162542A CN 112798084 B CN112798084 B CN 112798084B
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- 238000012360 testing method Methods 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000001514 detection method Methods 0.000 claims abstract description 34
- 230000007246 mechanism Effects 0.000 claims abstract description 20
- 238000005070 sampling Methods 0.000 claims description 6
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000007689 inspection Methods 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 25
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 8
- 239000003345 natural gas Substances 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
- G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
- G01F25/15—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters specially adapted for gas meters
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B11/00—Automatic controllers
- G05B11/01—Automatic controllers electric
- G05B11/36—Automatic controllers electric with provision for obtaining particular characteristics, e.g. proportional, integral, differential
- G05B11/42—Automatic controllers electric with provision for obtaining particular characteristics, e.g. proportional, integral, differential for obtaining a characteristic which is both proportional and time-dependent, e.g. P. I., P. I. D.
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D7/00—Control of flow
- G05D7/06—Control of flow characterised by the use of electric means
- G05D7/0617—Control of flow characterised by the use of electric means specially adapted for fluid materials
- G05D7/0629—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means
- G05D7/0676—Control of flow characterised by the use of electric means specially adapted for fluid materials characterised by the type of regulator means by action on flow sources
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Fluid Mechanics (AREA)
- Measuring Volume Flow (AREA)
Abstract
The standard meter method gas flow testing device comprises a bracket, a detection mechanism and a centrifugal fan, wherein the detection mechanism comprises a ball valve, a standard meter, a steady flow tank and a converging tank, the converging tank is arranged at the lower part of the bracket, the steady flow tank is arranged at the upper end of the bracket, one side of the converging tank is connected with the centrifugal fan through a hose, the upper end of the converging tank is connected with the lower end of the ball valve, the upper end of the ball valve is connected with the lower end of the standard meter through a first pipeline, the upper end of the standard meter is connected with the lower end of the steady flow tank through a second pipeline, the pressure sensor is arranged on the second pipeline, and a meter interface to be detected is arranged at one side of the steady flow tank; aiming at the problems of error expansion and the like caused by the difference between the detection working condition of a laboratory and the actual use working condition of a flowmeter in the conventional gas flow detection and inspection time, the on-site service type standard meter method gas flow testing device can save the standby time of the flow parameter testing device, improve the use efficiency of laboratory equipment of enterprises and bring remarkable economic benefit.
Description
Technical Field
The invention relates to the field of flow metering equipment, in particular to a standard meter method gas flow testing device and a variable frequency regulation control algorithm thereof.
Background
Flow metering is an important parameter in energy metering, and has a universal connection with national economy development and people's life. The flow metering is not related from gas meters and water meters for metering and charging in resident families and heat meters for heat supply to crude oil and natural gas trade settlement at import and export in China. Particularly, with the great development of natural gas oil fields, natural gas is becoming a material for people to live as a high-quality and high-efficiency energy source. Especially, the rapid promotion of the 'western gas east transport' project will continuously transport the natural gas resources in northwest of China to the wide market in the eastern part through underground pipelines. Therefore, the accuracy of detecting and calibrating the gas flow is the most important link in the transmission or tracing of the flow value, not only relates to the economic benefits of both trade parties, but also has important social benefits for the development of national economy in China.
The gas flow detection is more complicated in liquid flow detection, the gas flow is more sensitive to the influence of temperature and pressure, and the requirements on the pipeline joint are higher. For the detection of the gas flowmeter, a sonic nozzle gas flow device, a standard meter gas flow calibration device and a bell-jar gas flow calibration device are generally adopted, the devices are large in size and heavy in weight, the devices are required to be used in an open environment, and the temperature and the pressure specified by national regulations cannot be ensured. And the sonic nozzle is used at a fixed point, the flow rate cannot be continuously regulated, and the wanted flow rate point cannot be calibrated. The gas flowmeter is sent to an appointed detection unit address for offline detection, and is retrieved after detection, so that the gas flowmeter usually needs one to two days to send back and forth, and the detection time is added, so that the gas flowmeter can be reloaded on the device for use only by one worship at the fastest time, the production stopping time of enterprises is greatly increased, and the production efficiency is reduced. How to shorten the detection time of the laboratory detection device, save time for a user of the detection device, improve the production efficiency, accurately detect the flow parameter detection device and form a difficult problem in the quality inspection field. In order to ensure high precision and short-time detection, a set of equipment for detecting the flow parameter testing device on site is required.
Disclosure of Invention
The invention aims to provide a standard meter method gas flow testing device and a variable frequency regulation control algorithm thereof.
In order to achieve the above object, the technical scheme of the present invention is as follows:
The standard meter method gas flow testing device is characterized by comprising a support, a detection mechanism and a centrifugal fan, wherein the detection mechanism comprises a ball valve, a standard meter, a steady flow tank and a confluence tank, the confluence tank is arranged at the lower part of the support, the steady flow tank is arranged at the upper end of the support, a third pipeline is arranged on one side of the confluence tank and connected with the centrifugal fan through a hose, the upper end of the confluence tank is connected with the lower end of the ball valve, the upper end of the ball valve is connected with the lower end of the standard meter through a first pipeline, the upper end of the standard meter is connected with the lower end of the steady flow tank through a second pipeline, a meter interface is arranged on one side of the steady flow tank, the detection mechanism is arranged on a vehicle body, the upper part of the vehicle body is provided with a fixed position which is used for accommodating a meter to be tested, the standard meter is connected with the meter in series, the meter to be tested is connected with the meter through a meter test meter pipeline, temperature sensor and a pressure sensor are arranged at two ends of the meter and the standard meter respectively, and the pressure sensor is arranged on the second pipeline.
The standard table adopts a gas roots flowmeter, the maximum error between Q t～Qmax is +/-1%, the maximum error between Q min～Qt is +/-2%, wherein Q t is 0.2Q max, and the repeatability is better than 0.1%.
The detection mechanism further comprises a display, an industrial personal computer, an adapter plate, a power supply box and a fan frequency converter, wherein the temperature sensor and the pressure sensor are both connected with the adapter plate, the power supply box supplies power for the display, the industrial personal computer, the temperature sensor, the pressure sensor and the centrifugal fan, and the fan frequency converter is connected with the centrifugal fan.
According to the variable frequency regulation control algorithm of the standard meter method gas flow testing device, the variable frequency regulation is used for stabilizing gas flow, the requirement of the standard meter method gas flow testing device regulation is met, the variable frequency regulation control algorithm adopts an incremental PID, the deviation is taken as e (k), and the control increment of two adjacent outputs of the PID controller is as follows:
△u(k)＝Kp[e(k)-e(k-1)]+Kie(k)+Kd[e(k)-2e(k-1)+e(k-2)]，
Wherein: k p is a proportionality coefficient; k i is an integral coefficient; k d is a differential coefficient; k is a sampling sequence number; e (k), e (k-1) and e (k-2) are the k-th, k-1-th and k-2-th sampling output offset values, respectively.
The frequency converter and the centrifugal fan are controlled by operation software of the industrial personal computer to form a stable air flow source for the standard meter and the tested meter, the industrial personal computer collects the pulse of the standard meter, the pulse of the tested meter, the pressure before the meter and the temperature after the meter, the data of the standard meter and the data of the tested meter enter the industrial personal computer through a data line, and the relative error of the tested meter is obtainedAnd repeatability, wherein: q m、Qs is the accumulated volume flow of the checked meter and the accumulated volume flow after standard meter temperature and pressure compensation respectively.
Aiming at the problems of error expansion and the like caused by the difference between the detection working condition of a laboratory and the actual use working condition of a flowmeter in the conventional gas flow detection and inspection time, the on-site service type standard meter method gas flow testing device can save the standby time of the flow parameter testing device, improve the use efficiency of laboratory equipment of enterprises and bring remarkable economic benefit.
Drawings
FIG. 1 is a schematic diagram of the front structure of the present invention;
FIG. 2 is a schematic side view of the present invention;
Fig. 3 is a schematic diagram of another side structure of the present invention.
Reference numerals:
1 detection mechanism, 2 centrifugal fan, 3 support, 4 ball valve, 5 standard meter,
6 Steady flow tank, 7 confluence tank, 8 first pipeline, 9 second pipeline, 10 third pipeline,
11 Interface of the detected meter, 12 temperature sensor, 13 pressure sensor, 14 display,
15 Industrial personal computers, 16 adapter plates, 17 power supply boxes, 18 fan frequency converters and 19 hoses.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The invention discloses a standard meter method gas flow testing device, which is shown in fig. 1, and comprises a bracket 3, a detection mechanism 1 and a centrifugal fan 2, wherein the detection mechanism 1 comprises a ball valve 4, a standard meter 5, a steady flow tank 6 and a confluence tank 7, the confluence tank 7 is arranged at the lower part of the bracket 3, the steady flow tank 6 is arranged at the upper end of the bracket 3, a third pipeline 10 is arranged at one side of the confluence tank 7, the third pipeline 10 is connected with the centrifugal fan 2 through a hose 19, and the upper end of the confluence tank 7 is connected with the lower end of the ball valve 4.
As shown in fig. 1 and 3, both ends of the detected meter and the standard meter 5 are provided with a temperature sensor 12 and a pressure sensor 13, and temperature and pressure compensation of on-site flow measurement is performed according to the temperatures and pressures measured by the temperature sensor 12 and the pressure sensor 13, so that the problem that the gas flow is sensitive to the temperature and the pressure in the pipeline and the environment is solved.
As shown in fig. 3, the upper end of the ball valve 4 is connected with the lower end of the standard meter 5 through a first pipeline 8, the upper end of the standard meter 5 is connected with the lower end of the steady flow tank 6 through a second pipeline 9, the pressure sensor 13 is arranged on the second pipeline 9, and a meter interface 11 to be inspected is arranged on one side of the steady flow tank 6.
The interface 11 of the detected meter adopts a DN80 pipeline, the first pipeline 8 and the second pipeline 9 at the upper end and the lower end of the standard meter 5 and the ball valve 4 adopt DN50 or DN100 pipelines, and preferably, the invention comprises two groups of detection mechanisms 1, wherein one group of detection mechanisms 1 adopts DN50 pipelines, and the other group of detection mechanisms 1 adopts DN100 pipelines.
The detection mechanism 1 is arranged on a vehicle body, a fixed position is arranged on the upper portion of the vehicle body and used for accommodating a detected meter, the standard meter 5 is connected with the detected meter in series, and the detected meter is connected with the detected meter interface 11 through a detected meter pipeline.
As shown in fig. 2, the detection mechanism 1 further includes a display 14, an industrial personal computer 15, an adapter plate 16, a power box 17 and a fan frequency converter 18, the temperature sensor 12 and the pressure sensor 13 are both connected with the adapter plate 16, the power box 17 supplies power to the display 14, the industrial personal computer 15, the temperature sensor 12, the pressure sensor 13 and the centrifugal fan 2, and the fan frequency converter 18 is connected with the centrifugal fan 2.
According to the preferred embodiment of the invention, the control algorithm of the variable frequency regulation is an incremental PID, compared with the traditional position PID, the position digital PID has the operation of accumulating the deviation e (k), and the operation amount is large after long-time operation, so that the integral saturation phenomenon is easy to generate; when the computer system fails, the jump of the output value u (k) will cause the executing mechanism to change greatly, so that the control system oscillates.
In order to improve the defects of a position type PID control algorithm, the invention provides an incremental type PID control, and control increments output by the position type PID controller twice adjacent are sent to an executing mechanism:
△u(k)＝Kp[e(k)-e(k-1)]+Kie(k)+Kd[e(k)-2e(k-1)+e(k-2)]，
Wherein: k p is a proportionality coefficient; k i is an integral coefficient; k d is a differential coefficient; k is a sampling sequence number; e (k), e (k-1) and e (k-2) are the k-th, k-1-th and k-2-th sampling output offset values, respectively.
Compared with the position type PID, the increment type PID outputs increment, thereby reducing the influence of misoperation of the control system and avoiding larger oscillation of the system.
The standard table 5 adopts a gas roots flowmeter, the maximum error between Q t～Qmax is +/-1%, the maximum error between Q min～Qt is +/-2%, wherein Q t is 0.2Q max, and the repeatability is better than 0.1%.
The fan frequency converter 18 and the centrifugal fan 2 are controlled by the operation software of the industrial personal computer 15 to form a stable air flow source for the standard meter 5 and the tested meter, the industrial personal computer 15 collects the pulse of the standard meter 5 and the pulse of the tested meter and the pressure before and temperature after the meter, the data of the standard meter and the data of the tested meter enter the industrial personal computer through a data line to obtain the relative error of the tested meterAnd repeatability, wherein: q m、Qs is the accumulated volume flow of the checked meter and the accumulated volume flow after standard meter temperature and pressure compensation respectively.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (5)
1. The standard meter method gas flow testing device is characterized by comprising a support, a detection mechanism and a centrifugal fan, wherein the detection mechanism comprises a ball valve, a standard meter, a steady flow tank and a confluence tank, the confluence tank is arranged at the lower part of the support, the steady flow tank is arranged at the upper end of the support, a third pipeline is arranged on one side of the confluence tank and connected with the centrifugal fan through a hose, the upper end of the confluence tank is connected with the lower end of the ball valve, the upper end of the ball valve is connected with the lower end of the standard meter through a first pipeline, the upper end of the standard meter is connected with the lower end of the steady flow tank through a second pipeline, a meter interface is arranged on one side of the steady flow tank, the detection mechanism is arranged on a vehicle body, the upper part of the vehicle body is provided with a fixed position which is used for accommodating a meter to be tested, the standard meter is connected with the meter in series, the meter to be tested is connected with the meter through a meter test meter pipeline, temperature sensor and a pressure sensor are arranged at two ends of the meter and the standard meter respectively, and the pressure sensor is arranged on the second pipeline.
2. The standard meter gas flow test set of claim 1, wherein the standard meter uses a gas flow meter with a maximum error between Q t～Qmax of ± 1% and a maximum error between Q min～Qt of ± 2%, wherein Q t is 0.2Q max and repeatability is better than 0.1%.
3. The standard meter method gas flow testing device of claim 1, wherein the detection mechanism further comprises a display, an industrial personal computer, an adapter plate, a power box and a fan frequency converter, the temperature sensor and the pressure sensor are both connected with the adapter plate, the power box supplies power for the display, the industrial personal computer, the temperature sensor, the pressure sensor and the centrifugal fan, and the fan frequency converter is connected with the centrifugal fan.
4. The variable frequency regulation control algorithm of the standard meter method gas flow test device according to claim 3, wherein the air flow is stabilized by variable frequency regulation, the requirement of the standard meter method gas flow test device regulation is met, the variable frequency regulation control algorithm adopts an incremental PID, the deviation is e (k), and the control increment of two adjacent outputs of the PID controller is as follows:
△u(k)＝Kp[e(k)-e(k-1)]+Kie(k)+Kd[e(k)-2e(k-1)+e(k-2)]，
Wherein: k p is a proportionality coefficient; k i is an integral coefficient; k d is a differential coefficient; k is a sampling sequence number; e (k), e (k-1) and e (k-2) are the k-th, k-1-th and k-2-th sampling output offset values, respectively.
5. The variable frequency regulation control algorithm according to claim 4, wherein the operation software of the industrial personal computer controls the frequency converter and the centrifugal fan to form a stable air flow source for the standard meter and the tested meter, the industrial personal computer collects the pulse of the standard meter and the pulse of the tested meter and the data of the pressure before and the temperature after the meter, the data of the standard meter and the data of the tested meter enter the industrial personal computer through a data line to obtain the relative error of the tested meterAnd repeatability, wherein: q m、Qs is the accumulated volume flow of the checked meter and the accumulated volume flow after standard meter temperature and pressure compensation respectively.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110162542.9A CN112798084B (en) | 2021-02-05 | 2021-02-05 | Standard meter method gas flow testing device and variable frequency adjustment control algorithm thereof |
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| CN202110162542.9A CN112798084B (en) | 2021-02-05 | 2021-02-05 | Standard meter method gas flow testing device and variable frequency adjustment control algorithm thereof |
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| CN112798084B true CN112798084B (en) | 2024-06-04 |
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2021
- 2021-02-05 CN CN202110162542.9A patent/CN112798084B/en active Active
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| CN202092737U (en) * | 2011-05-30 | 2011-12-28 | 上海工业自动化仪表研究院 | Standard meter type gas flow standard device capable of self-check |
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