CN106813007A - A kind of intelligent valve positioner - Google Patents
A kind of intelligent valve positioner Download PDFInfo
- Publication number
- CN106813007A CN106813007A CN201510861044.8A CN201510861044A CN106813007A CN 106813007 A CN106813007 A CN 106813007A CN 201510861044 A CN201510861044 A CN 201510861044A CN 106813007 A CN106813007 A CN 106813007A
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- China
- Prior art keywords
- valve
- signal
- piezo electric
- air chamber
- control unit
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K31/00—Actuating devices; Operating means; Releasing devices
- F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
- F16K31/126—Actuating devices; Operating means; Releasing devices actuated by fluid the fluid acting on a diaphragm, bellows, or the like
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K37/00—Special means in or on valves or other cut-off apparatus for indicating or recording operation thereof, or for enabling an alarm to be given
- F16K37/0025—Electrical or magnetic means
- F16K37/0041—Electrical or magnetic means for measuring valve parameters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K37/00—Special means in or on valves or other cut-off apparatus for indicating or recording operation thereof, or for enabling an alarm to be given
- F16K37/0075—For recording or indicating the functioning of a valve in combination with test equipment
- F16K37/0083—For recording or indicating the functioning of a valve in combination with test equipment by measuring valve parameters
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Indication Of The Valve Opening Or Closing Status (AREA)
Abstract
The invention discloses a kind of intelligent valve positioner, it is characterised in that：Including control unit, the deviation of valve position setting signal and feedback signal is received, realize high-precision conversion, computing and PWM output functions；Valve position collecting unit, the spool position of the controlled valve of measurement in real time；Execution unit, is made up of two piezo electric valve Formulas I/P electrical equipment converting units, and piezo electric valve exports pwm control signal controlling switch by ARM controller, realizes the air inlet and exhaust of executing agency's air chamber；Controlled system, is made up of pneumatic diaphragn actuating mechanism and Direct Travel plunger valve, and pneumatic diaphragn actuating mechanism is arranged on valve, and the air chamber of pneumatic diaphragn actuating mechanism connects two voltage valves；Front end input block, there is provided power supply and setting signal.Intelligent valve positioner of the present invention can realize being installed separately for locator and valve, realize Poul Dorset Sheep magnetic field, solve the problems, such as the high capacity of input circuit.
Description
Technical field
The present invention relates to a kind of valve positioner, especially a kind of valve positioner of Based Intelligent Control.
Background technology
Valve positioner, by structure point pneumatic positioner valve, electropneumatic valve positioner and intelligent valve positioner, it is the main accessories of regulating valve, generally supported the use with pneumatic control valve, it receives the output signal of adjuster, then goes to control pneumatic control valve with its output signal, after valve events are adjusted, the displacement of valve rod feeds back to valve positioner further through mechanical device, and valve position situation is transmitted to Upper system by electric signal.
In some severe field working conditions environment, such as too high, too low environment temperature, there are strong vibrations in valve or pipeline, and site environment has intense radiation, strong electromagnetic, intelligent valve positioner is arranged on valve and can not work very well, and the life-span can also substantially reduce.
Various mechanical transmission mechanisms and contact-cup anemometer are commonly used as sensor, so often there are the bad phenomenons such as abrasion, oxidation, aging, mechanical hysteresis, measurement and control accuracy is had a strong impact on.And Hall sensor, as a kind of contactless, linear, high-precision sensor, then can greatly compensate for the deficiency of traditional displacement detecting sensor.
Because the input impedance of intelligent valve positioner is higher, and increase with the increase of input current, therefore carrying load ability to Regulate signal has requirement higher.And under normal circumstances, the output on-load ability of digital regulated instrument is less than 300 ohm, therefore the carrying load ability of adjuster output control signal must be checked when from intelligent electric valve positioner, 500 ohm is should be greater than, the normal work of locator when just can guarantee that big aperture.The setting signal isolator in input signal loop, can increase the carrying load ability of control signal.
The content of the invention
Goal of the invention of the invention is：For above-mentioned problem, there is provided one kind can Poul Dorset Sheep, load capacity intelligent valve positioner high additionally provides the control method of intelligent valve positioner.
The technical solution adopted by the present invention is as follows：
Intelligent valve positioner of the present invention, including
The collection of valve position Unit：Position sensor detects the displacement of valve element, and displacement is converted into voltage signal, and position detection amplifying circuit amplifies voltage signal, is sent to A/D collection plates, and voltage signal is converted into digital signaling zero 01, uploads to control unit by A/D collection plates；
Front end input block：The 4mA-20mA current signals of host computer input are converted into voltage 1V-5V by zener diode, as power supply, are used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；Current signal 4-25mA is sent to A/D collection plates by inspection stream and amplifying circuit simultaneously, and current signal is converted into digital signaling zero 02, uploads to control unit by A/D collection plates；
Control unit：The digital signaling zero 02 that the digital signaling zero 01 and front end input block of the collecting unit upload of valve position are uploaded is received, is compared, if value of 002 value more than 001, control unit sends to piezo electric valve and performs signal 01;If value of 001 value more than 002, control unit sends to piezo electric valve and performs signal 02；Reception comes from the signal of the pressure sensor set in executing agency's air chamber, is contrasted with preset value, if being more than preset value, sends alarm to alarm and performs signal；Use ARM controller；
Execution unit：Receive and perform signal 01, boosting piezo electric valve Vl is opened, output bleed pressure P1 increases, executing agency's air chamber pressure increase increases valve opening, reduces the two deviation;Receive and perform signal 02, exhaust piezo electric valve V2 is opened, be vented by gas extraction system and reduce output bleed pressure P2, executing agency's air chamber pressure reduces reduces valve opening, and the two deviation reduces；
Controlled system：It is made up of pneumatic diaphragn actuating mechanism and Direct Travel plunger valve, pneumatic diaphragn actuating mechanism is arranged on valve, the air chamber of pneumatic diaphragn actuating mechanism connects two voltage valves, one of them is connected to source of the gas control air inlet, and another is connected to gas extraction system；Pressure sensor, and control unit connection are provided with executing agency's air chamber.
Further, zena's safety barrier is respectively arranged with the power channel and signalling channel of the front end input block, reduces the input impedance in input signal loop, increase the carrying load ability of input signal.
Further, alarm is connected with described control unit, when the alarm for receiving control unit transmission performs signal, sends alarm signal.
Further, position sensor is magneto-dependent sensor described in the collecting unit of valve position, is arranged at the outer wall of magnetic valve.
Further, the execution unit is made up of two piezo electric valve Formulas I/P electrical equipment converting units, and piezo electric valve exports pwm control signal controlling switch by ARM controller, realizes the air inlet and exhaust of executing agency's air chamber.
A kind of intelligent valve positioner control method, including following steps：
Step one：The 4mA-20mA current signals that host computer sends are received, is changed by I/V, be converted to 1V-5V voltages, used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；The signal is by inspection stream simultaneously and amplifies, and is transferred to A/D collection plates, in uploading to control unit, as valve position setting signal；
Step 2：The actual opening amount signal of valve is picked up by stem position sensor, is changed by A/D and is changed into digitally encoded signal；
Step 3：The digitally encoded signal of actual opening amount signal conversion is contrasted with the digital coding of front end input block input (setting) signal in CPU, calculates the two deviation；
Step 4：If deviation exceeds positioning precision, CPU output orders make corresponding ON/OFF piezoelectricity valve events, i.e.,:When setting signal is more than valve position feedback, boosting piezo electric valve Vl is opened, and output bleed pressure P1 increases, executing agency's air chamber pressure increase is that valve opening increases, and reduces the two deviation;Piezo electric valve V2 being vented if setting signal is less than valve position feedback to open, being vented by gas extraction system and reduce output bleed pressure P1, it is that valve opening reduces that executing agency's air chamber pressure reduces, and the two deviation reduces；The size of output bleed pressure is adjusted by CPU control piezo electric valves makes input signal reach new balance with valve position.
The operation principle of intelligent valve positioner：The displacement of the valve that position sensor is measured is converted into digitally encoded signal, the digitally encoded signal converted with the current signal that host computer is input into is compared, calculate deviation, if deviation exceeds positioning precision, the air pressure of executing agency's air chamber is adjusted by piezo electric valve, input signal is reached new balance with valve position.
In sum, by adopting the above-described technical solution, the beneficial effects of the invention are as follows：
1st, measurement, control accuracy are high.
The detection of valve location has used magneto-dependent sensor, it is a kind of contactless, linear, high-precision sensor, the bad phenomenons such as the abrasion, oxidation, the aging, mechanical hysteresis that occur when can overcome mechanical transmission mechanism and contact-cup anemometer as sensor, improve measurement and control accuracy.
2nd, the load capacity of signal requirement higher is resolved.
The setting signal isolator in input signal loop, can increase the carrying load ability of control signal, more than 500 ohm, reach the job requirement of locator.
Brief description of the drawings
Examples of the present invention will be described by way of reference to the accompanying drawings, wherein：
Fig. 1 is the structural representation of intelligent valve positioner of the present invention.
Specific embodiment
All features disclosed in this specification, or disclosed all methods or during the step of, in addition to mutually exclusive feature and/or step, can combine by any way.
This specification（Including any accessory claim, summary）Disclosed in any feature, unless specifically stated otherwise, can alternative features equivalent by other or with similar purpose replaced.I.e., unless specifically stated otherwise, each feature is an example in a series of equivalent or similar characteristics.
Such as Fig. 1, intelligent valve positioner of the present invention, including
The collection of valve position Unit：Position sensor detects the displacement of valve element, and displacement is converted into voltage signal, and position detection amplifying circuit amplifies voltage signal, is sent to A/D collection plates, and voltage signal is converted into digital signaling zero 01, uploads to control unit by A/D collection plates；
Front end input block：The 4mA-20mA current signals of host computer input are converted into voltage 1V-5V by zener diode, as power supply, are used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；Current signal 4-25mA is sent to A/D collection plates by inspection stream and amplifying circuit simultaneously, and current signal is converted into digital signaling zero 02, uploads to control unit by A/D collection plates；
Control unit：The digital signaling zero 02 that the digital signaling zero 01 and front end input block of the collecting unit upload of valve position are uploaded is received, is compared, if value of 002 value more than 001, control unit sends to piezo electric valve and performs signal 01;If value of 001 value more than 002, control unit sends to piezo electric valve and performs signal 02；Reception comes from the signal of the pressure sensor set in executing agency's air chamber, is contrasted with preset value, if being more than preset value, sends alarm to alarm and performs signal；Use ARM controller；
Execution unit：Receive and perform signal 01, boosting piezo electric valve Vl is opened, output bleed pressure P1 increases, executing agency's air chamber pressure increase increases valve opening, reduces the two deviation;Receive and perform signal 02, exhaust piezo electric valve V2 is opened, be vented by gas extraction system and reduce output bleed pressure P2, executing agency's air chamber pressure reduces reduces valve opening, and the two deviation reduces；
Controlled system：It is made up of pneumatic diaphragn actuating mechanism and Direct Travel plunger valve, pneumatic diaphragn actuating mechanism is arranged on valve, the air chamber of pneumatic diaphragn actuating mechanism connects two voltage valves, one of them is connected to source of the gas control air inlet, and another is connected to gas extraction system；Pressure sensor, and control unit connection are provided with executing agency's air chamber.
In implementation, zena's safety barrier is respectively arranged with the power channel and signalling channel of the front end input block, reduces the input impedance in input signal loop, increase the carrying load ability of input signal.
In implementation, alarm is connected with described control unit, when the alarm for receiving control unit transmission performs signal, sends alarm signal.
In implementation, position sensor is magneto-dependent sensor described in the collecting unit of valve position, is arranged at the outer wall of magnetic valve.
In implementation, the execution unit is made up of two piezo electric valve Formulas I/P electrical equipment converting units, and piezo electric valve exports pwm control signal controlling switch by ARM controller, realizes the air inlet and exhaust of executing agency's air chamber.
A kind of intelligent valve positioner control method, including following steps：
Step one：The 4mA-20mA current signals that host computer sends are received, is changed by I/V, be converted to 1V-5V voltages, used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；The signal is by inspection stream simultaneously and amplifies, and is transferred to A/D collection plates, in uploading to control unit, as valve position setting signal；
Step 2：The actual opening amount signal of valve is picked up by stem position sensor, is changed by A/D and is changed into digitally encoded signal；
Step 3：The digitally encoded signal of actual opening amount signal conversion is contrasted with the digital coding of front end input block input (setting) signal in CPU, calculates the two deviation；
Step 4：If deviation exceeds positioning precision, CPU output orders make corresponding ON/OFF piezoelectricity valve events, i.e.,:When setting signal is more than valve position feedback, boosting piezo electric valve Vl is opened, and output bleed pressure P1 increases, executing agency's air chamber pressure increase is that valve opening increases, and reduces the two deviation;Piezo electric valve V2 being vented if setting signal is less than valve position feedback to open, being vented by gas extraction system and reduce output bleed pressure P1, it is that valve opening reduces that executing agency's air chamber pressure reduces, and the two deviation reduces；The size of output bleed pressure is adjusted by CPU control piezo electric valves makes input signal reach new balance with valve position.
The invention is not limited in foregoing specific embodiment.The present invention expands to any new feature for disclosing in this manual or any new combination, and disclose any new method or process the step of or any new combination.
Claims (6)
1. a kind of intelligent valve positioner, it is characterised in that：Including valve position collecting unit：Position sensor detects the displacement of valve element, and displacement is converted into voltage signal, and position detection amplifying circuit amplifies voltage signal, is sent to A/D collection plates, and voltage signal is converted into digital signaling zero 01, uploads to control unit by A/D collection plates；
Front end input block：The 4mA-20mA current signals of host computer input are converted into voltage 1V-5V by zener diode, as power supply, are used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；Current signal 4-25mA is sent to A/D collection plates by inspection stream and amplifying circuit simultaneously, and current signal is converted into digital signaling zero 02, uploads to control unit by A/D collection plates；
Control unit：The digital signaling zero 02 that the digital signaling zero 01 and front end input block of the collecting unit upload of valve position are uploaded is received, is compared, if value of 002 value more than 001, control unit sends to piezo electric valve and performs signal 01;
If value of 001 value more than 002, control unit sends to piezo electric valve and performs signal 02；Reception comes from the signal of the pressure sensor set in executing agency's air chamber, is contrasted with preset value, if being more than preset value, sends alarm to alarm and performs signal；Use ARM controller；
Execution unit：Receive and perform signal 01, boosting piezo electric valve Vl is opened, output bleed pressure P1 increases, executing agency's air chamber pressure increase increases valve opening, reduces the two deviation;Receive and perform signal 02, exhaust piezo electric valve V2 is opened, be vented by gas extraction system and reduce output bleed pressure P2, executing agency's air chamber pressure reduces reduces valve opening, and the two deviation reduces；
Controlled system：It is made up of pneumatic diaphragn actuating mechanism and Direct Travel plunger valve, pneumatic diaphragn actuating mechanism is arranged on valve, the air chamber of pneumatic diaphragn actuating mechanism connects two voltage valves, one of them is connected to source of the gas control air inlet, and another is connected to gas extraction system；Pressure sensor, and control unit connection are provided with executing agency's air chamber.
2. a kind of intelligent valve positioner according to claim 1, it is characterised in that：Zena's safety barrier is respectively arranged with the power channel and signalling channel of the front end input block, the input impedance in input signal loop is reduced, increases the carrying load ability of input signal.
3. a kind of intelligent valve positioner according to claim 1, it is characterised in that：Alarm is connected with described control unit, when the alarm for receiving control unit transmission performs signal, alarm signal is sent.
4. a kind of intelligent valve positioner according to claim 1, it is characterised in that：Position sensor is magneto-dependent sensor described in the collecting unit of valve position, is arranged at the outer wall of magnetic valve.
5. a kind of intelligent valve positioner according to claim 1, it is characterised in that：The execution unit is made up of two piezo electric valve Formulas I/P electrical equipment converting units, and piezo electric valve exports pwm control signal controlling switch by ARM controller, realizes the air inlet and exhaust of executing agency's air chamber.
6. a kind of intelligent valve positioner control method, it is characterised in that：Including following steps：
Step one：The 4mA-20mA current signals that host computer sends are received, is changed by I/V, be converted to 1V-5V voltages, used for CPU, peripheral hardware hardware circuit and piezoelectricity valve-driving circuit；The signal is by inspection stream simultaneously and amplifies, and is transferred to A/D collection plates, in uploading to control unit, as valve position setting signal；
Step 2：The actual opening amount signal of valve is picked up by stem position sensor, is changed by A/D and is changed into digitally encoded signal；
Step 3：The digitally encoded signal of actual opening amount signal conversion is contrasted with the digital coding of front end input block input (setting) signal in CPU, calculates the two deviation；
Step 4：If deviation exceeds positioning precision, CPU output orders make corresponding ON/OFF piezoelectricity valve events, i.e.,:When setting signal is more than valve position feedback, boosting piezo electric valve Vl is opened, and output bleed pressure P1 increases, executing agency's air chamber pressure increase is that valve opening increases, and reduces the two deviation;Piezo electric valve V2 being vented if setting signal is less than valve position feedback to open, being vented by gas extraction system and reduce output bleed pressure P1, it is that valve opening reduces that executing agency's air chamber pressure reduces, and the two deviation reduces；The size of output bleed pressure is adjusted by CPU control piezo electric valves makes input signal reach new balance with valve position.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510861044.8A CN106813007A (en) | 2015-12-01 | 2015-12-01 | A kind of intelligent valve positioner |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510861044.8A CN106813007A (en) | 2015-12-01 | 2015-12-01 | A kind of intelligent valve positioner |
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| CN106813007A true CN106813007A (en) | 2017-06-09 |
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| CN201510861044.8A Pending CN106813007A (en) | 2015-12-01 | 2015-12-01 | A kind of intelligent valve positioner |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107145092A (en) * | 2017-06-23 | 2017-09-08 | 重庆阿卡雷科技有限公司 | intelligent positioner control method and device |
| CN107489801A (en) * | 2017-09-21 | 2017-12-19 | 安徽荣达阀门有限公司 | A kind of high sensitivity steam valve |
| CN110985747A (en) * | 2019-08-09 | 2020-04-10 | 浙江中控技术股份有限公司 | Piezoelectric valve positioner and rapid positioning method thereof |
| CN111720618A (en) * | 2020-05-29 | 2020-09-29 | 深圳万讯自控股份有限公司 | Coding type stroke-adaptive lightning protection valve positioner and control method |
| CN113685610A (en) * | 2021-08-24 | 2021-11-23 | 中冶京诚工程技术有限公司 | Valve position signal transmitter |
| CN114001194A (en) * | 2020-07-28 | 2022-02-01 | 青岛海尔空调电子有限公司 | Method and device for adjusting and monitoring opening degree of electronic expansion valve |
-
2015
- 2015-12-01 CN CN201510861044.8A patent/CN106813007A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107145092A (en) * | 2017-06-23 | 2017-09-08 | 重庆阿卡雷科技有限公司 | intelligent positioner control method and device |
| CN107489801A (en) * | 2017-09-21 | 2017-12-19 | 安徽荣达阀门有限公司 | A kind of high sensitivity steam valve |
| CN107489801B (en) * | 2017-09-21 | 2019-03-26 | 安徽荣达阀门有限公司 | A kind of high sensitivity steam valve |
| CN110985747A (en) * | 2019-08-09 | 2020-04-10 | 浙江中控技术股份有限公司 | Piezoelectric valve positioner and rapid positioning method thereof |
| CN110985747B (en) * | 2019-08-09 | 2021-12-28 | 浙江中控技术股份有限公司 | Piezoelectric valve positioner and rapid positioning method thereof |
| CN111720618A (en) * | 2020-05-29 | 2020-09-29 | 深圳万讯自控股份有限公司 | Coding type stroke-adaptive lightning protection valve positioner and control method |
| CN114001194A (en) * | 2020-07-28 | 2022-02-01 | 青岛海尔空调电子有限公司 | Method and device for adjusting and monitoring opening degree of electronic expansion valve |
| CN114001194B (en) * | 2020-07-28 | 2024-05-14 | 青岛海尔空调电子有限公司 | Method and device for adjusting and monitoring opening of electronic expansion valve |
| CN113685610A (en) * | 2021-08-24 | 2021-11-23 | 中冶京诚工程技术有限公司 | Valve position signal transmitter |
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