CN202812387U - Constant pressure differential protecting control device for boiler water supply electric-control valve - Google Patents
Constant pressure differential protecting control device for boiler water supply electric-control valve Download PDFInfo
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- CN202812387U CN202812387U CN 201220360220 CN201220360220U CN202812387U CN 202812387 U CN202812387 U CN 202812387U CN 201220360220 CN201220360220 CN 201220360220 CN 201220360220 U CN201220360220 U CN 201220360220U CN 202812387 U CN202812387 U CN 202812387U
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Abstract
The utility model relates to a constant pressure differential protecting control device for a boiler water supply electric-control valve, in particular to an industrial control device. The constant pressure differential protecting control device for the boiler water supply electric-control valve comprises a PLC (programmable logic controller) control system, pressure transmitters I and II, a frequency converter and an operation panel. The PLC control system comprises a CPU (central processing unit) module, a power module, an Ethernet communication module, an analog input module, a digital input module, an analog output module and a digital output module, wherein the power module, the Ethernet communication module, the analog input module, the digital input module, the analog output module and the digital output module are respectively connected with the CPU module. The pressure transmitters I and II are disposed on inner pipe walls of front and rear pipes of the boiler water supply electric-control valve respectively. The frequency converter is connected to a motor of a boiler water supply pump and controls operation of the motor of the boiler water supply pump. The CPU module automatically controls frequency of the frequency converter according to pressure differential. The frequency of the frequency converter is controlled to adjust flow of the boiler water supply pump. Difference between front and rear pressures of the boiler water supply electric-control valve is small and stable. The constant pressure differential protecting control device for the boiler water supply electric-control valve has the advantages of safety, high control precision, low energy consumption, high automation level, high reliability and the like.
Description
Technical field
The utility model relates to a kind of industrial control device, particularly a kind of constant-pressure drop boiler water supply motorized adjustment valve protection control gear.
Background technique
In a lot of boiler feed systems, the boiler water supply pump generally is to need the H-Max Demand Design and with the driving of motor power frequency drive manner, then adopt the aperture of automatic controlling system water supply electric control valve to carry out liquid level control by boiler.Therefore raw water service pump lift surplus is very large, and the hydraulic pressure that electric control valve is produced is very high, needs the motor of electric control valve to be in higher load condition or overload state during the motorized adjustment valve events and could export enough power and move.When boiler is moving with wave, can cause that water level frequently changes; the water supply automatic control system can frequently provide action command to electric control valve; make the rear electric control valve motor overheating of the long-time high load of electric control valve or overwork; cause the electric control valve thermal protection for motors and quit work, thereby make water level uncontrollable.In this case, if boiler liquid level this moment is very low, can not in time strengthens again water output and carry out moisturizing, pot even producing boiler blast can occur doing, be breakneck potential safety hazard.
The model utility content
The purpose of this utility model is to shut down idle safety problem for prior art boiler water supply electric control valve because its motor internal overload protection causes electric control valve, a kind of energy Effective Raise boiler safety is provided, reaches high-accuracy and constant differential pressure control effect, makes the constant-pressure drop boiler water supply motorized adjustment valve protection control gear that boiler feed pump Energy Intensity Reduction, automaticity and reliability are high, simple to operate, man-machine interface is friendly, easy to adjust, simple in structure.
The technological scheme that the utility model adopts for achieving the above object is: a kind of constant-pressure drop boiler water supply motorized adjustment valve protection control gear; this motorized adjustment valve protection control gear comprises the PLC control system; the pressure transmitter I; the pressure transmitter II; frequency variator and operation panel; the PLC control system comprises CPU module and the power module that is connected with the CPU module respectively; the ethernet communication module; analog input module I; analog input module II; digital quantity input module; analog output module; the digital output module; the pressure transmitter I is installed on the outside tube wall of boiler water supply electric control valve front-end pipelines; the pressure transmitter II is installed on the outside tube wall of boiler water supply electric control valve rear end pipeline; the pressure transmitter I; the output terminal of pressure transmitter II is connected with the input end of analog input module I respectively; frequency variator is connected on the motor of boiler feed pump and controls the machine operation of boiler feed pump; the output terminal of frequency variator is connected with the input end of analog input module II and digital quantity input module respectively; the input end of frequency variator is connected with the output terminal of analog output module and digital output module respectively; analog input module I; analog input module II and digital quantity input module are connected with the CPU module by core bus; analog output module and digital output module are connected with the CPU module by core bus, and operation panel is connected with the ethernet communication module.
Wherein said analog input module I is 8 tunnel 12 4-20mA 2 lines analog amount load modules processed, pressure transmitter I, pressure transmitter II are 2 lines 4-20mA pressure transmitter processed, and pressure transmitter I, pressure transmitter II are connected with the input end of analog input module I by 2 core cables respectively.
Wherein said analog input module II is 8 tunnel 12 4-20mA 4 lines analog amount load modules processed, digital quantity input module is 32 railway digital amount load modules, and the output terminal of frequency variator is connected by the input end of multicore cable with analog input module II and digital quantity input module respectively.
Wherein said analog output module is 8 tunnel 12 4-20mA analog input modules, the digital output module is 32 railway digital amount output modules, and the input end of frequency variator is connected by the output terminal of multicore cable with analog output module and digital output module respectively.
Wherein said power module is the DC24V DC power supplier.
Wherein said PLC control system is the S7-300 series of PLC, the CPU module is CPU315-2DP, power module is PS307, the ethernet communication module is CP343-1 Lean, analog input module I, analog input module II and analog output module are SM331, and digital quantity input module, digital output module are SM321.
The quantity of wherein said frequency variator and the quantity of boiler feed pump are complementary, i.e. boiler feed water pump work of the corresponding control of frequency variator.
Have following beneficial effect owing to adopted such scheme, the utility model to compare with existing other similar technology:
1, improves boiler safety
After using the constant-pressure drop boiler water supply motorized adjustment valve protection control gear of the utility model, by the pressure transmitter I, before II gathers the boiler water supply electric control valve, rear pressure signal, pressure signal is passed to the CPU module of PLC control system by analog input module I, the CPU module is controlled the frequency of frequency variator automatically according to pressure difference, the uninterrupted of frequency adjustment boiler feed pump by the control frequency variator, boiler water supply electric control valve front and back pressure reduction diminishes and is stable, the power that needs when making boiler water supply motorized adjustment valve events diminishes, and the motor of electric control valve can not shut down because the overload heating causes protection; Electric control valve phenomenon of being failure to actuate out of control can not appear in boiler (especially Emergency time) in running; Significantly improved boiler safety.
2, can reach the effect of high-accuracy and constant differential pressure control
In the constant-pressure drop boiler water supply motorized adjustment valve protection control gear of the utility model, be connected with analog input module II by digital quantity input module between frequency variator and the CPU module, obtain frequency variator work at present status information, by operation panel (can be touch screen or PC computer) the differential pressure controlling value is set, the control parameter foundation of Fuzzy PID when processing as the differential pressure control information; Pressure transmitter I, II gather boiler water supply electric control valve rear and front end current pressure value, after standard signal is sent into analog input module I, analog input module I is given signal the CPU module again, the PLC control system is exported to frequency variator by analog output module with the pressure reduction controlling value after by the fuzzy computing, make frequency variator carry out VFC to boiler feed pump, the experiment proved that in running overshoot can be above 5% of differential pressure value is set.
3, boiler feed pump Energy Intensity Reduction
In the constant-pressure drop boiler water supply motorized adjustment valve protection control gear of the utility model; owing to adopt frequency variator VFC boiler feed pump to feed water; make boiler feed pump when normal production; can not work according to demand when not needing at full speed power frequency running; namely under the speed of needs, turn round; can effectively reduce the power consumption of boiler feed pump; owing to design for security consideration; boiler feed water pumping head surplus is large; and boiler is when normally producing; boiler feed pump only needs turn round under about 60% speed at full speed and gets final product, so compared with prior art can save electric weight 30% at least.
4, automaticity and reliability are high, simple to operate
When using the constant-pressure drop boiler water supply motorized adjustment valve protection control gear of the utility model; only need press parameter arranges button; namely entering the differential pressure controlling value arranges state or differential pressure control parameter state is set; at this moment, the operator only need by operation panel (can be touch screen or PC computer), can arrange status parameter setting to differential pressure control; the differential pressure control procedure is full automatic; reliability is high, does not need to use miscellaneous equipment, and it is very convenient to operate.
5, man-machine interface is friendly
Use in the constant-pressure drop boiler water supply motorized adjustment valve protection control gear process of the utility model; can show in real time the dynamic value of differential pressure and controlling value is set by operation panel (display screen of touch screen or PC computer) is upper; arrange in the differential pressure parametric procedure by operation panel again; also can show the parameter value that arranges by operation panel; operating process is very clear, and man-machine interface is friendly.
6, simple, good, the reliable operation, easy to adjust of parameter modification stability of the constant-pressure drop boiler water supply motorized adjustment valve protection control gear overall structure of the utility model.
Below in conjunction with drawings and Examples the utility model constant-pressure drop boiler water supply motorized adjustment valve protection control gear is described further.
Description of drawings
Fig. 1 is the block diagram of the utility model constant-pressure drop boiler water supply motorized adjustment valve protection control gear.
Embodiment
As shown in Figure 1; the utility model constant-pressure drop boiler water supply motorized adjustment valve protection control gear; it is the permanent difference pressure control device of a kind of closed loop fuzzy PID; this motorized adjustment valve protection control gear comprises PLC control system 1; the pressure transmitter I; the pressure transmitter II; frequency variator and operation panel; PLC control system 1 comprises CPU module and the power module that is connected with the CPU module respectively; the ethernet communication module; analog input module I; analog input module II; digital quantity input module; analog output module; the digital output module; electric control valve is installed in the pipeline of boiler feed water pump output terminal; the pressure transmitter I is installed on the outside tube wall of boiler water supply electric control valve front-end pipelines; the pressure transmitter II is installed on the outside tube wall of boiler water supply electric control valve rear end pipeline; the pressure transmitter I; the output terminal of pressure transmitter II is connected with the input end of analog input module I respectively; frequency variator is connected on the motor of boiler feed pump and controls the machine operation of boiler feed pump; the quantity of frequency variator and the quantity of boiler feed pump are complementary; the motor of transducer power and boiler feed pump is complementary; a frequency variator and a boiler feed pump only are shown among the figure; the quantity of frequency variator can be many; as long as corresponding with the quantity of boiler feed pump, namely a frequency variator correspondence is controlled a boiler feed water pump work.The output terminal of frequency variator is connected with the input end of analog input module II and digital quantity input module respectively, the input end of frequency variator is connected with the output terminal of analog output module and digital output module respectively, analog input module I, analog input module II and digital quantity input module are connected with the CPU module by core bus, analog output module and digital output module are connected by core bus and CPU module, and operation panel is connected with the ethernet communication module.Each module of PLC control system 1 is separately positioned on the PLC backboard, and links to each other by the PLC backboard.
Described analog input module I is 8 tunnel 12 4-20mA 2 lines analog amount load modules processed, pressure transmitter I, pressure transmitter II are 2 lines 4-20mA pressure transmitter processed, and pressure transmitter I, pressure transmitter II are connected with 1 tunnel analog input channel terminal (not shown) of analog input module I input end by 2 core cables respectively.Described analog input module II is 8 tunnel 12 4-20mA 4 lines analog amount load modules processed, digital quantity input module is 32 railway digital amount load modules, and the output terminal of frequency variator is connected with 1 tunnel analog input channel (not shown) of analog input module II input end and 3 railway digital amount input channel (not shown)s of digital quantity input module input end by multicore cable respectively.Described analog output module is 8 tunnel 12 4-20mA analog input modules, the digital output module is 32 railway digital amount output modules, the input end of frequency variator respectively 1 tunnel analog input channel (not shown) by multicore cable and analog output module output terminal and digital output module output terminal 2 the tunnel be that digital output passage respective channel terminal (not shown) is connected.Described power module is the DC24V DC power supplier, and PLC control system 1 inner all modules are powered by the PLC backboard by the DC24V DC power supplier.PLC control system 1 is the S7-300 series of PLC, the CPU module is CPU315-2DP, power module is PS307, the ethernet communication module is CP343-1 Lean, analog input module I, analog input module II and analog output module are SM331, and digital quantity input module, digital output module are SM321.
During work, main minute following step in the motorized adjustment valve protection control gear control procedure: differential pressure controlling value, electric control valve rear and front end pressure acquisition and the collection of frequency variator working state, differential pressure control information processing, differential pressure controlling value output control, demonstration that the electric control valve two ends are set monitor; Its step is as follows:
Step 1: the differential pressure controlling value that the electric control valve two ends are set: by the differential pressure controlling value of operation panel (can be touch screen or PC computer) input electric control valve rear and front end, the PLC control system is by its inner ethernet communication module and operation panel communication, the differential pressure controlling value of the electric control valve rear and front end of inputting on the PLC control system read operation panel is passed to the differential pressure controlling value of the electric control valve rear and front end set by the PLC backboard CPU module of PLC control system;
Step 2: electric control valve rear and front end pressure acquisition and frequency variator working state gather, electric control valve rear and front end pressure acquisition: from being installed in the pressure transmitter I on the pipeline of boiler water supply electric control valve front end and back end, the pressure transmitter II gathers the current force value in electric control valve rear and front end, the data that collect are through the pressure transmitter I, the II inside chip converts standard 4-20mA analog amount signal transmission to, transfer signals to the analog input module I of PLC control system 1 by 2 core cables, pressure signal is passed to the CPU module of PLC control system through the analog input module I of PLC control system and calculated for it; The frequency variator working state gathers: adopting boiler feed pump pattern of a transducer drive is the boiler coupling, the power of motor of transducer power and boiler feed pump is complementary, the CPU module that frequency variator work at present status information data is passed to the PLC control system by analog input module II and the digital quantity input module of PLC control system, be specially: frequency variator work at present status information data is transferred to the analog input module II of PLC control system and the input end of digital quantity input module by multicore cable, pass to the CPU module by analog input module II and digital quantity input module, for monitoring, analog input module II is with the instantaneous velocity of transmission boiler feed pump motor, and digital quantity input module is with switching signal and the trouble signal of transmission boiler feed pump;
Step 3: the differential pressure control information is processed: according to the current force value in differential pressure controlling value, the electric control valve rear and front end of electric control valve rear and front end, frequency variator work at present status information data, calculate the pressure reduction controlling value by the CPU module of PLC control system by fuzzy PID algorithm;
Step 4: the output control of differential pressure controlling value: the CPU module of PLC control system is passed to frequency variator with the pressure reduction controlling value that calculates in the step 3 by the analog output module of PLC control system, and the rotating speed that frequency variator changes boiler feed pump according to the frequency conversion of pressure reduction controlling value is realized the control to differential pressure before and after the electric control valve; Simultaneously, the CPU module of PLC control system by the PLC control system digital output module output control frequency variator start and stop or failure reset information to frequency variator; As manually press the start and stop key on operation panel, the CPU module of PLC control system namely can be passed to frequency variator with start stop signal by the digital output module of PLC control system after receiving signal; When boiler feed system broke down, the CPU module can quit work automatically by digital output module controls frequency variator, and boiler feed pump is corresponding quitting work also, and the control frequency variator automatically quits work and mainly realized by software control;
Step 5: show to monitor: the differential pressure of the actual differential pressure value at the differential pressure controlling value at the electric control valve two ends of display working condition, setting, electric control valve two ends and electric control valve control parameter on the display screen (not shown) of operation panel.
As variation of the present utility model: when the quantity of boiler feed pump was N (N for greater than 1 integer) platform, the quantity of frequency variator also be N (N for greater than 1 integer) platform, needs only the quantity of frequency variator and the quantity of boiler feed pump and is complementary; When the quantity of boiler feed pump and frequency variator is many, the quantity of the digital quantity input module of PLC control system, digital output module, analog input module (comprising analog input module I, II), analog output module with the matching relationship of N is respectively: the quantity of digital quantity input module is 3/32 of N *, 2/32 of the quantity N * of digital output module, the quantity N of analog input module/8+1 piece, the quantity N of analog output module/8 piece can add in the quantity of aforementioned matching relationship quantity any amount spare module simultaneously; The model of each module is not limited to the cited model of above-described embodiment in the PLC control system, also can be the device that has other model of same or similar performance with above-mentioned model, as long as the conversion of doing all belongs to category of the present utility model in scope of the present utility model.
Claims (7)
1. constant-pressure drop boiler water supply motorized adjustment valve protection control gear; it is characterized in that; this motorized adjustment valve protection control gear comprises the PLC control system; the pressure transmitter I; the pressure transmitter II; frequency variator and operation panel; the PLC control system comprises CPU module and the power module that is connected with the CPU module respectively; the ethernet communication module; analog input module I; analog input module II; digital quantity input module; analog output module; the digital output module; the pressure transmitter I is installed on the outside tube wall of boiler water supply electric control valve front-end pipelines; the pressure transmitter II is installed on the outside tube wall of boiler water supply electric control valve rear end pipeline; the pressure transmitter I; the output terminal of pressure transmitter II is connected with the input end of analog input module I respectively; frequency variator is connected on the motor of boiler feed pump and controls the machine operation of boiler feed pump; the output terminal of frequency variator is connected with the input end of analog input module II and digital quantity input module respectively; the input end of frequency variator is connected with the output terminal of analog output module and digital output module respectively; analog input module I; analog input module II and digital quantity input module are connected with the CPU module by core bus; analog output module and digital output module are connected by core bus and CPU module, and operation panel is connected with the ethernet communication module.
2. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1; it is characterized in that; described analog input module I is 8 tunnel 12 4-20mA 2 lines analog amount load modules processed; pressure transmitter I, pressure transmitter II are 2 lines 4-20mA pressure transmitter processed, and pressure transmitter I, pressure transmitter II are connected with the input end of analog input module I by 2 core cables respectively.
3. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1; it is characterized in that; described analog input module II is 8 tunnel 12 4-20mA 4 lines analog amount load modules processed; digital quantity input module is 32 railway digital amount load modules, and the output terminal of frequency variator is connected by the input end of multicore cable with analog input module II and digital quantity input module respectively.
4. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1; it is characterized in that; described analog output module is 8 tunnel 12 4-20mA analog input modules; the digital output module is 32 railway digital amount output modules, and the input end of frequency variator is connected by the output terminal of multicore cable with analog output module and digital output module respectively.
5. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1 is characterized in that described power module is the DC24V DC power supplier.
6. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1; it is characterized in that; described PLC control system is the S7-300 series of PLC; the CPU module is CPU315-2DP; power module is PS307; the ethernet communication module is CP343-1 Lean, and analog input module I, analog input module II and analog output module are SM331, and digital quantity input module, digital output module are SM321.
7. constant-pressure drop boiler water supply motorized adjustment valve protection control gear as claimed in claim 1 is characterized in that the quantity of described frequency variator and the quantity of boiler feed pump are complementary, i.e. boiler feed water pump work of the corresponding control of frequency variator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220360220 CN202812387U (en) | 2012-07-24 | 2012-07-24 | Constant pressure differential protecting control device for boiler water supply electric-control valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220360220 CN202812387U (en) | 2012-07-24 | 2012-07-24 | Constant pressure differential protecting control device for boiler water supply electric-control valve |
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| CN202812387U true CN202812387U (en) | 2013-03-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 201220360220 Withdrawn - After Issue CN202812387U (en) | 2012-07-24 | 2012-07-24 | Constant pressure differential protecting control device for boiler water supply electric-control valve |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102777887A (en) * | 2012-07-24 | 2012-11-14 | 柳州高新区欧亚自动化设备有限责任公司 | Protection control device and protection control method for constant-differential-pressure electric adjusting valve for water-supply of boiler |
| CN103529883A (en) * | 2013-10-22 | 2014-01-22 | 解波 | Programmable logic controller (PLC)-based temperature and liquid level combined monitoring system |
| CN106480471A (en) * | 2016-11-04 | 2017-03-08 | 柳州高新区欧亚自动化设备有限责任公司 | EMD Continuous leaching process chemical combination groove pH value control device and its control method |
| CN108181223A (en) * | 2017-12-26 | 2018-06-19 | 北京航空航天大学 | A kind of measuring device and measuring method for porous biomaterial permeability |
-
2012
- 2012-07-24 CN CN 201220360220 patent/CN202812387U/en not_active Withdrawn - After Issue
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102777887A (en) * | 2012-07-24 | 2012-11-14 | 柳州高新区欧亚自动化设备有限责任公司 | Protection control device and protection control method for constant-differential-pressure electric adjusting valve for water-supply of boiler |
| CN103529883A (en) * | 2013-10-22 | 2014-01-22 | 解波 | Programmable logic controller (PLC)-based temperature and liquid level combined monitoring system |
| CN106480471A (en) * | 2016-11-04 | 2017-03-08 | 柳州高新区欧亚自动化设备有限责任公司 | EMD Continuous leaching process chemical combination groove pH value control device and its control method |
| CN106480471B (en) * | 2016-11-04 | 2018-05-22 | 柳州高新区欧亚自动化设备有限责任公司 | EMD Continuous leaching process chemical combination slot pH value control devices and its control method |
| CN108181223A (en) * | 2017-12-26 | 2018-06-19 | 北京航空航天大学 | A kind of measuring device and measuring method for porous biomaterial permeability |
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| AV01 | Patent right actively abandoned |
Granted publication date: 20130320 Effective date of abandoning: 20140611 |
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