CN111623593A - Intelligent unit system for freezing, refrigerating and refrigerating system and control method thereof - Google Patents
Intelligent unit system for freezing, refrigerating and refrigerating system and control method thereof Download PDFInfo
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- CN111623593A CN111623593A CN202010515621.9A CN202010515621A CN111623593A CN 111623593 A CN111623593 A CN 111623593A CN 202010515621 A CN202010515621 A CN 202010515621A CN 111623593 A CN111623593 A CN 111623593A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D29/00—Arrangement or mounting of control or safety devices
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25D—REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
- F25D2600/00—Control issues
- F25D2600/06—Controlling according to a predetermined profile
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- Air Conditioning Control Device (AREA)
Abstract
The invention discloses an intelligent unit system for a freezing, refrigerating and refrigerating system and a control method thereof. The system comprises a compressor controller, wherein the compressor controller comprises a switching value input interface, a switching value output interface, a PT100 input interface, an analog quantity output interface, an energy carrier position acquisition input interface, an Ethernet interface and a serial port communication interface. The method comprises a generalized control method, an energy loading position high-precision acquisition method and a compressor load limit control method. The invention can meet the diversified design requirements of the compressor system, and the control of the freezing and refrigerating system is more generalized, accurate and intelligent by measuring the energy loading voltage percentage method and controlling the current and the exhaust pressure limit of the host machine.
Description
Technical Field
The invention relates to an intelligent unit of a freezing and refrigerating system and a control method of the intelligent unit.
Background
Due to the diversity of user demands, the existing freezing and refrigerating control unit system has the problem of poor universality, designers need to repeatedly design according to individual non-standard requirements, a large amount of investment of manpower and material resources is caused, and meanwhile, the error rate of the system is continuously increased.
On the other hand, the control of the conventional system is relatively extensive, the compressor position resistance value is influenced by the difference of instruments and the temperature of the compressor, the measurement deviation is relatively large, and the control precision is influenced.
Thirdly, the existing control system does not have a loading position limiting function, and a host is overloaded or the exhaust pressure is high due to various reasons in the use process of a user, so that the compressor is in a fault shutdown state, the service life of the compressor is influenced, and the production of the user is delayed.
Disclosure of Invention
The invention provides an intelligent unit system for a freezing, refrigerating and refrigerating system and a control method thereof, and aims to provide an intelligent unit system for a freezing, refrigerating and refrigerating system, which comprises the following steps: (1) the generalization control of the intelligent freezing and refrigerating system is realized; (2) the detection precision of the resistance value of the loading position of the compressor is improved; (3) and the position control of the compressor is realized.
The technical scheme of the invention is as follows:
the utility model provides an intelligent unit system for freezing refrigeration system, includes the compressor controller, the compressor controller includes switching value input interface, switching value output interface, PT100 input interface, analog quantity output interface, energy carry the position to gather input interface, ethernet interface and serial ports communication interface.
As a further improvement of the method, the switching value input interface has at least 16 paths, the switching value output interface has at least 24 paths, the PT100 input interface has at least 4 paths, the analog value input interface has at least 8 paths, the analog value output interface has at least 2 paths, and the ethernet interface has at least 2 paths.
As a further improvement of the method, the compressor controller further comprises a USB interface for connecting a mobile memory, and the collected data and the calculation result are automatically stored in the mobile memory during the operation process of the compressor controller; when the cloud platform requests data from the compressor controller, the compressor controller uploads the data in the mobile memory to the cloud platform.
As a further improvement of the method, all wiring lines connected with the compressor controller respectively use character marks and are distinguished by different colors, instrument points with the same function are connected on the same group of interface terminals of the compressor controller, and common instrument points of different units are placed on the same group of terminals.
As a further development of the method, the control method comprises several control steps; each control step comprises a plurality of logic modules, and when the control step is executed, the type of the compressor is judged, the corresponding logic module is selected according to the type of the compressor, and then the substeps in the logic modules are executed.
As a further improvement of the method, each control step is respectively corresponding to an execution identifier, before the type of the compressor is judged, whether the execution identifier is valid is judged, if yes, the control step is executed, and otherwise, the control step is skipped.
As a further improvement of the method, the compressor types comprise a single-machine refrigeration compressor, a brine unit, an NH3 high-temperature machine, a CO2 low-temperature machine, a CO2 defrosting compressor, a single-machine double-stage refrigeration compressor and a double-stage match-match refrigeration compressor;
the control step comprises a starting step, a variable frequency adjusting step, an internal volume ratio adjusting step, an oil content temperature detecting step, an oil filter differential pressure detecting step and a single-double oil pump control step.
As a further improvement of the method, the method for collecting the energy carrying position comprises the following steps: and adding base voltage on two sides of the bit loading resistor, and determining the bit loading percentage by calculating the ratio of the voltage of the middle measuring position of the bit loading resistor to the base voltage.
As a further improvement of the method, the bit loading control is realized by the following method: detecting exhaust pressure, and executing a load shedding electromagnetic valve instruction when the exhaust pressure is greater than the sum of a set value and a return difference; when the exhaust pressure is greater than the set value and less than the sum of the set value and the return difference, executing an instruction of closing the load reduction electromagnetic valve; when the exhaust pressure is smaller than the set value and larger than the difference between the set value and the return difference, executing a load-increasing electromagnetic valve closing instruction; when the exhaust pressure is smaller than the difference between the set value and the return difference, the compressor allows the load-increasing electromagnetic valve to be opened.
Compared with the prior art, the invention has the following beneficial effects: (1) the hardware platform provided by the system can meet the requirement of more than 95% of the number of the meters of the machine type, is provided with a special measuring channel for customizing the energy carrying position, and can meet the requirement of a high-precision energy carrying position acquisition method; (2) the invention provides a generalized flow method for a refrigeration system, designers can integrate related control logics of various types of compressors and control logics of various nonstandard requirements into one control system software, increase and decrease the steps and functions according to needs, and can automatically execute corresponding control flows according to actual compressor types, thereby realizing the generalization and intellectualization of the system control method and reducing the development cost and the maintenance cost of the system; (3) the invention collects the energy loading position by the voltage percentage method, eliminates the loading position measuring error caused by instrument or temperature difference, and has high precision; (4) the intelligent unit controls the action of the electromagnetic valve by detecting and early warning the current and the exhaust pressure of the compressor host, limits the running load position of the compressor, and regulates and controls the current and the exhaust pressure of the host in advance, so that the fault shutdown caused by the overload of the host and the high alarm of the exhaust pressure is avoided, the fault shutdown frequency of the compressor is successfully reduced, and the requirement of users on continuous production is met; (5) the system has the capability of edge computing and edge storage, and data is uploaded according to the request of the cloud platform, so that the data pressure of the cloud platform is reduced; (6) the wiring of the controller adopts a fool-proof design, so that the production efficiency is improved, and the operation error rate is reduced.
Drawings
FIG. 1 is a diagram of an interface layout for a smart cell compressor controller.
Fig. 2 is a schematic diagram of the energy carrying potential voltage detection.
FIG. 3 is a schematic flow chart of the present intelligent unit for bit limit control.
FIG. 4 is a schematic flow chart of the intelligent unit performing a generalized control.
Detailed Description
The technical scheme of the invention is explained in detail in the following with the accompanying drawings:
an intelligent cell system for a refrigerated refrigeration system including a compressor controller, the compressor controller comprising: 16 paths of switching value input, 24 paths of switching value output, 4 paths of PT100 input, 8 paths of 4-20 mA input, 2 paths of energy carrying position signal acquisition, 2 paths of 4-20 mA output, 2 paths of Ethernet communication and 1 path of 485 communication. The number of the points can cover more than 95% of the machine types of the refrigeration compressor, the functions are comprehensive, and the hardware requirements of universalization, precision and intellectualization of the control unit are met.
The interface components of the compressor controller are shown in fig. 1, and include:
16 switching value inputs: X00-X07, X10-X17;
24 switching value outputs: Y00-Y07, Y10-Y17 and Y20-Y27;
4-way PT100 input: three-wire systems R0-R4;
8 paths of 4-20 mA input: AI 0-AI 3, AI 5-AI 6, AI 8-AI 9;
2-path energy carrying position signal acquisition: AI4, AI 7;
2 paths of 4-20 mA outputs: I0/V0, I1/V1;
2-path Ethernet communication;
1 path of 485 communication: d +, D-.
The compressor controller also comprises a USB interface used for connecting the mobile memory, and the compressor controller automatically stores the acquired data and the calculation result into the mobile memory in the running process, so that the edge storage and the edge calculation are realized. When the cloud platform requests data from the compressor controller, the compressor controller uploads the data in the mobile memory to the cloud platform, and data pressure of the cloud platform is reduced.
The wiring part connected with the compressor controller adopts a fool-proof design, each wiring line respectively uses character marks and is distinguished by different colors, instrument points with the same function are connected on the same group of interface terminals of the compressor controller, and common instrument points of different units are placed on the same group of terminals, so that the production in a workshop is facilitated, the production efficiency is improved, and the error rate is reduced.
The controller also increases the 24V output. The conventional PLC only has two terminals of AI + and AI-, and a pressure sensor usually needs to be powered by a loop, the 24V + of a direct-current power supply needs to be connected to the + terminal of the sensor, and the-terminal of the sensor is connected to the AI + terminal of the PLC again, so that the shielding of the wiring of a twisted pair is not facilitated. The controller integrates 24V +, AI + and AI-, and the sensor + terminal and the sensor-terminal are directly connected to the 24V + terminal and the AI + terminal of the controller integration.
Referring to fig. 2, the method for the intelligent unit to collect the energy bits is: and adding base voltage on two sides of the bit loading resistor, and determining the bit loading percentage by calculating the ratio of the voltage of the middle measuring position of the bit loading resistor to the base voltage. In particular, V+And V-Based on the voltage, AI4 is the measurement point voltage feedback, V+AI4 and V-Respectively connected to the corresponding terminals of the controller. The controller collects V in real time+AI4 and V-Three point voltage by the formula Z = (AI 4-V)-）/（V+－V-) The current carry bit can be calculated. The measuring method is independent of the change of the resistance value R, can solve the problem of the measurement error of the load signal caused by the difference of the instrument and the temperature, and can shield V from the measurement result of the method+Due to the influence of voltage fluctuation, the load position measurement is more accurate.
As shown in fig. 3, the method for implementing bit loading control by the intelligent unit includes: detecting exhaust pressure, and executing a load shedding electromagnetic valve instruction when the exhaust pressure is greater than the sum of a set value and a return difference; when the exhaust pressure is greater than the set value and less than the sum of the set value and the return difference, executing an instruction of closing the load reduction electromagnetic valve; when the exhaust pressure is smaller than the set value and larger than the difference between the set value and the return difference, executing a load-increasing electromagnetic valve closing instruction; when the exhaust pressure is smaller than the difference between the set value and the return difference, the compressor allows the load-increasing electromagnetic valve to be opened. The intelligent unit detects the early warning exhaust pressure through the control method, limits the operation loading position of the compressor, regulates and controls the exhaust pressure in advance, can avoid the fault shutdown caused by high exhaust pressure alarm, successfully reduces the fault shutdown frequency of the compressor, and guarantees the requirement of users on continuous production.
The control method of the system is a generalized program method, which comprises a plurality of control steps; each control step comprises a plurality of logic modules. Each control step is respectively corresponding to an execution identifier, before the type of the compressor is judged, whether the execution identifier is valid is judged, if yes, the control step is executed, and otherwise, the control step is skipped. When the control step is executed, the type of the compressor is judged, the corresponding logic module is selected according to the type of the compressor, and then the substeps in the logic module are executed.
The designer can set the execution identifier of the control step according to the non-standard requirement of the customer, so as to achieve the purpose of increasing and reducing functions, and meanwhile, the program can automatically select the corresponding logic module according to the type of the compressor. The designer only needs to maintain one set of system program to cover most compressors.
Specifically, the compressor types comprise a single-unit refrigeration compressor, a brine unit, an NH3 high-temperature machine, a CO2 low-temperature machine, a CO2 defrosting compressor, a single-unit double-stage refrigeration compressor and a double-stage matching refrigeration compressor.
The control step comprises a starting step, a variable frequency adjusting step, an internal volume ratio adjusting step, an oil content temperature detecting step, an oil filter differential pressure detecting step and a single-double oil pump control step.
The controller is also provided with a self-checking function, when the model of the unit is selected, signals of all channels are detected, and when the channel with the signal input does not detect the signals, the fault of the sensor is output; when the channel without signal input detects the signal, the output line is wrong.
Referring to fig. 4, an automatic start-up control process is taken as an example to show how the intelligent unit can implement a method for generalizing control processes of different units, so as to solve the problem of repeated design of designers caused by various types and non-standard combinations.
Compressor type = 1: represents a stand-alone refrigeration compressor;
compressor type = 2: represents a brine unit;
compressor type = 3: represents a NH3 high-temperature machine;
compressor type = 4: represents a CO2 cryocooler;
compressor type = 5: representative of a CO2 defrost compressor;
compressor type = 6: represents a single-unit two-stage refrigeration compressor;
compressor type = 7: representing a two-stage match refrigeration compressor.
The brine unit is automatically started and controlled by the outlet water temperature, when the outlet water temperature is higher than the set starting temperature, the brine unit executes the automatic starting process, the automatic starting of other compressor types is controlled by the local starting button instruction, and when the local starting button instruction is 1, the automatic starting process is executed.
When the type of the compressor is 6 or 7, because two energy loading positions of a high-pressure level and a low-pressure level exist, a high-pressure level zero loading position signal and a low-pressure level zero loading position signal are detected firstly after a starting process is started, and when the two zero loading position signals are both 1, a subsequent process is executed; when the compressor type is not 6 or 7, the compressor has only one energy carrying bit, only the zero carrying bit signal is detected, and when the zero carrying bit signal is 1, the subsequent process is executed.
When the type of the compressor is 7, starting the high-pressure-level host, then adjusting the high-pressure-level energy, and when the low-pressure level meets the starting condition, starting the low-pressure-level host, and then adjusting the low-pressure-level energy; when the compressor type is not 7, performing a host start; when the compressor type is 3, performing energy adjustment according to the condensing pressure; when the compressor type is 5, performing energy adjustment according to the exhaust pressure; when the compressor type is 2, energy adjustment is performed according to the outlet water temperature.
The difference of the automatic starting processes of the 7 different units is that corresponding control processes are respectively executed according to the description, the processes are the same, the control processes are universal, and the same action is executed.
Fig. 4 shows only the generalization of the automatic start control flow, and on the basis, if the control of a non-standard single-double oil pump is added at the moment, only one time needs to be added in the control flow. The non-standard control needs to be added in 7 different compressor type programs in the past, namely 7 non-standard programs appear, the universal idea of the intelligent unit solves the problem of repeated design of designers caused by various types and non-standard combinations, the design efficiency is improved, and the design error is reduced.
Claims (9)
1. An intelligent unit system for a refrigeration system, comprising: the energy storage device comprises a compressor controller, wherein the compressor controller comprises a switching value input interface, a switching value output interface, a PT100 input interface, an analog quantity output interface, an energy carrying position acquisition input interface, an Ethernet interface and a serial port communication interface.
2. The intelligent unit system for a refrigerated refrigeration system of claim 1 wherein: the switching value input interface at least comprises 16 paths, the switching value output interface at least comprises 24 paths, the PT100 input interface at least comprises 4 paths, the analog quantity input interface at least comprises 8 paths, the analog quantity output interface at least comprises 2 paths, and the Ethernet interface at least comprises 2 paths.
3. The intelligent unit system for a refrigerated refrigeration system of claim 1 wherein: the compressor controller also comprises a USB interface used for connecting the mobile memory, and the compressor controller automatically stores the acquired data and the calculation result into the mobile memory in the running process; when the cloud platform requests data from the compressor controller, the compressor controller uploads the data in the mobile memory to the cloud platform.
4. The intelligent unit system for a refrigerated refrigeration system of claim 1 wherein: the wiring lines connected with the compressor controller are respectively marked by characters and distinguished by different colors, instrument points with the same function are connected on the same group of interface terminals of the compressor controller, and common instrument points of different units are placed on the same group of terminals.
5. The control method of the intelligent unit system for the refrigerating and freezing refrigeration system according to any one of claims 1 to 4, wherein: the control method comprises a plurality of control steps; each control step comprises a plurality of logic modules, and when the control step is executed, the type of the compressor is judged, the corresponding logic module is selected according to the type of the compressor, and then the substeps in the logic modules are executed.
6. The control method according to claim 5, wherein: each control step is respectively corresponding to an execution identifier, before the type of the compressor is judged, whether the execution identifier is valid is judged, if yes, the control step is executed, and otherwise, the control step is skipped.
7. The control method according to claim 5, wherein: the compressor types comprise a single-machine refrigeration compressor, a brine unit, an NH3 high-temperature machine, a CO2 low-temperature machine, a CO2 defrosting compressor, a single-machine double-stage refrigeration compressor and a double-stage matching refrigeration compressor;
the control step comprises a starting step, a variable frequency adjusting step, an internal volume ratio adjusting step, an oil content temperature detecting step, an oil filter differential pressure detecting step and a single-double oil pump control step.
8. The control method according to claim 5, wherein the method for collecting the energy bits comprises: and adding base voltage on two sides of the bit loading resistor, and determining the bit loading percentage by calculating the ratio of the voltage of the middle measuring position of the bit loading resistor to the base voltage.
9. The control method according to claim 5, wherein the bit loading control is implemented by: detecting exhaust pressure, and executing a load shedding electromagnetic valve instruction when the exhaust pressure is greater than the sum of a set value and a return difference; when the exhaust pressure is greater than the set value and less than the sum of the set value and the return difference, executing an instruction of closing the load reduction electromagnetic valve; when the exhaust pressure is smaller than the set value and larger than the difference between the set value and the return difference, executing a load-increasing electromagnetic valve closing instruction; when the exhaust pressure is smaller than the difference between the set value and the return difference, the compressor allows the load-increasing electromagnetic valve to be opened.
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| CN202010515621.9A CN111623593A (en) | 2020-06-09 | 2020-06-09 | Intelligent unit system for freezing, refrigerating and refrigerating system and control method thereof |
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Citations (6)
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| CN1151512A (en) * | 1995-10-18 | 1997-06-11 | Lg电子株式会社 | Device and method for controlling temperature of refrigerating chamber in refrigerator |
| CN1322975A (en) * | 2000-05-04 | 2001-11-21 | 瓦苏技术有限公司 | Mountable electronic controller |
| CN201786626U (en) * | 2010-09-15 | 2011-04-06 | 重庆埃泰克能源科技有限公司 | Logic control system for air compressor |
| CN105223917A (en) * | 2015-09-16 | 2016-01-06 | 北京丰电科技股份有限公司 | A kind of complex control system based on dissimilar compressed air unit and method |
| CN206249043U (en) * | 2016-10-21 | 2017-06-13 | 北京和利时智能技术有限公司 | A kind of mining intrinsic safety type programable controller |
| CN107339851A (en) * | 2017-08-08 | 2017-11-10 | 苏州新亚科技有限公司 | A kind of intelligent management system for freezing and refrigeration |
-
2020
- 2020-06-09 CN CN202010515621.9A patent/CN111623593A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1151512A (en) * | 1995-10-18 | 1997-06-11 | Lg电子株式会社 | Device and method for controlling temperature of refrigerating chamber in refrigerator |
| CN1322975A (en) * | 2000-05-04 | 2001-11-21 | 瓦苏技术有限公司 | Mountable electronic controller |
| CN201786626U (en) * | 2010-09-15 | 2011-04-06 | 重庆埃泰克能源科技有限公司 | Logic control system for air compressor |
| CN105223917A (en) * | 2015-09-16 | 2016-01-06 | 北京丰电科技股份有限公司 | A kind of complex control system based on dissimilar compressed air unit and method |
| CN206249043U (en) * | 2016-10-21 | 2017-06-13 | 北京和利时智能技术有限公司 | A kind of mining intrinsic safety type programable controller |
| CN107339851A (en) * | 2017-08-08 | 2017-11-10 | 苏州新亚科技有限公司 | A kind of intelligent management system for freezing and refrigeration |
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Application publication date: 20200904 |