Ammonia refrigerant remote integrated automatic control system and method

Abstract

The invention provides an ammonia refrigerant remote integrated automatic control system and method, and belongs to the technical field of automatic control. The ammonia refrigerant remote integrated automatic control system comprises a data acquisition subsystem and an intelligent control subsystem, wherein the data acquisition subsystem is used for acquiring running state data of the ammonia refrigerant system; and the intelligent control subsystem is used for setting threshold data of the operation of the ammonia refrigerant system, processing the state data and the threshold data according to a preset first control rule or a preset second control rule, and controlling the operation of the ammonia refrigerant system. According to the invention, the problems of remote accurate monitoring and energy-saving operation of the ammonia refrigerant system can be solved.

Description

Technical Field

[0001] The present disclosure relates to the field of automation control technology, and particularly to a remote integrated automatic control system and method for ammonia refrigerants. Background Art

[0002] In the field of refrigeration technology, ammonia refrigeration is widely used in many fields such as industrial refrigeration and cold storage due to its good thermodynamic performance, high refrigeration efficiency, and cost advantages. With the development of technology and the continuous improvement of industrial automation, higher requirements are put forward for the performance and control accuracy of ammonia refrigeration systems.

[0003] During the operation of traditional ammonia refrigerant systems, there are many problems to be solved urgently. In terms of control, most adopt a combination of on-site manual operation and simple automation control. Manual operation is not only inefficient but also difficult to achieve real-time and accurate monitoring and regulation of system operation parameters, easily leading to increased energy consumption of the refrigeration system and unstable refrigeration effects. In addition, the architecture of traditional ammonia refrigeration systems is relatively single, lacking an effective distributed control mechanism. Once a key component or control link fails, it is easy to seriously affect the operation of the entire system, and even cause shutdowns, etc., bringing huge losses to production and operation. Summary of the Invention

[0004] Embodiments of the present disclosure provide a remote integrated automatic control system and method for ammonia refrigerants to solve the problems of remote precise monitoring and energy-saving operation of ammonia refrigerant systems.

[0005] In a first aspect, embodiments of the present disclosure provide a remote integrated automatic control system for ammonia refrigerants, used to control an ammonia refrigerant system, including: a data acquisition subsystem and an intelligent control subsystem; wherein The data acquisition subsystem is used to collect the status data of the operation of the ammonia refrigerant system; The intelligent control subsystem is used to set the threshold data of the operation of the ammonia refrigerant system, and is also used to process the status data and threshold data according to a preset first control rule or second control rule to control the operation of the ammonia refrigerant system.

[0006] In an exemplary embodiment of the present disclosure, the intelligent control subsystem includes an operation station, a master station, and at least one slave station; The operation station is used to display the status data of the operation of the ammonia refrigerant system, and is also used to set the threshold data, the first control rule, and the second control rule of the operation of the ammonia refrigerant system.

[0007] The master station is used to generate data acquisition control instructions, send the data acquisition control instructions to each slave station, and is also used to process the status data and threshold data according to the first control rule or the second control rule, generate control rule instructions, and send the control rule instructions to each slave station; The slave station is used to transmit the status data of the operation of the ammonia refrigerant system to the master station according to the data acquisition control instructions, and is also used to control the operation of the ammonia refrigerant system according to the control rule instructions.

[0008] In an exemplary embodiment of the present disclosure, the ammonia refrigerant system includes an ammonia circulation subsystem and a refrigerant circulation subsystem; wherein, The ammonia circulation subsystem includes a compressor unit, a condenser unit, a thermosiphon tank, a high-pressure liquid storage tank unit, a gas-liquid separator unit, and an evaporator unit; Among them, the compressor unit is used to prepare the input ammonia gas into first ammonia gas and transport the first ammonia gas to the condenser unit; The condenser unit includes a plurality of condensers, which are used to cool the first ammonia gas and transform it into first ammonia liquid; and transport the first ammonia liquid to the thermosiphon tank; The thermosiphon tank is used to adjust the flow rate of the first ammonia liquid output by the condenser unit and transport the first ammonia liquid to the high-pressure liquid storage tank unit; The high-pressure liquid storage tank unit is used to store the first ammonia liquid and transport the first ammonia liquid to the gas-liquid separator unit; The gas-liquid separator unit is used to separate the first ammonia liquid input from the high-pressure storage tank from the second ammonia gas output by the evaporator unit, transport the first ammonia liquid to the evaporator unit, and transport the second ammonia gas to the compressor unit; The evaporator unit is used to enable the first ammonia liquid to absorb the heat of the first refrigerant in the refrigerant circulation subsystem to obtain a second refrigerant, and transport the second refrigerant to the refrigerant circulation subsystem; The refrigerant circulation subsystem includes a refrigerant storage tank unit and a refrigerant circulation pump; The refrigerant storage tank unit is used to store the refrigerant; The refrigerant circulation pump is used to transport the first refrigerant in the refrigerant storage tank unit to the evaporator unit.

[0009] In an exemplary embodiment of the present disclosure, the data acquisition subsystem includes: A first temperature sensor is arranged at the outlet position of the compressor unit and is used to detect the temperature value of the first ammonia gas output by the compressor; A second temperature sensor, arranged at the inlet position of the compressor unit, for detecting the temperature value of the ammonia sucked into the compressor; A third temperature sensor, arranged at the inlet position of the evaporator unit, for detecting the temperature value of the first refrigerant input to the evaporator unit; A fourth temperature sensor, arranged at the outlet position of the evaporator unit, for detecting the temperature value of the second refrigerant output from the evaporator unit; A distributed temperature detection module, arranged in the refrigerant storage tank unit, for detecting the temperature value of the refrigerant in the refrigerant storage tank unit; wherein, the distributed temperature detection module includes a fifth temperature sensor, a sixth temperature sensor, a seventh temperature sensor and an eighth temperature sensor; A ninth temperature sensor, arranged in the high-pressure liquid storage barrel, for detecting the temperature value of the first ammonia liquid in the high-pressure liquid storage barrel; A first pressure sensor, arranged at the inlet position of the compressor unit, for detecting the pressure value at the inlet of the compressor unit; A second pressure sensor, arranged at the outlet position of the compressor unit, for detecting the pressure value at the outlet of the compressor unit; A third pressure sensor, arranged in the high-pressure liquid storage barrel unit, for detecting the pressure value of the first ammonia liquid in the high-pressure liquid storage barrel unit; A first liquid level sensor, for detecting the liquid level value in the high-pressure liquid storage barrel unit; A second liquid level sensor, for detecting the liquid level value in the refrigerant storage tank unit; A flow sensor, for detecting the flow rate of the refrigerant output by the variable-frequency refrigerant circulation pump; An ambient temperature sensor, for detecting the ambient temperature value of the ammonia refrigerant system.

[0010] In an exemplary embodiment of the present disclosure, the operation station includes: A condenser priority control module, for accumulating the operation time of each condenser in the condenser unit to generate a priority queue, and starting the condenser with the shortest operation time first; A hysteresis pressure control module, for when the pressure value at the outlet of the compressor unit is greater than the first preset pressure value threshold range for a duration exceeding the preset time, starting the condensers one by one until the pressure value at the outlet of the compressor unit returns to within the first preset pressure value threshold range; A refrigerant stratified temperature control module, for when the weighted average temperature value detected by the distributed temperature detection module is greater than the preset temperature value threshold, controlling the operation of the ammonia refrigerant system to eliminate the temperature difference of the refrigerant in the refrigerant storage tank unit; A dual - threshold alarm module, which is used to trigger an audible and visual alarm and issue an emergency shutdown instruction when it is detected that the temperature value of the first ammonia liquid in the high - pressure liquid storage barrel unit is greater than a second preset temperature value and / or the pressure of the first ammonia liquid is greater than a second preset pressure value; A compressor low - temperature protection module, which is used to stop sucking ammonia when it is detected that the inlet temperature value of the compressor unit is lower than a third preset temperature value.

[0011] In an exemplary embodiment of the present disclosure, the first control rule includes: Adjust the starting quantity of the condensers in the condenser unit according to the pressure value at the outlet of the compressor unit; Adjust the rotational speed of the refrigerant circulation pump according to the comparison result between the temperature value of the second refrigerant output by the evaporator unit and a fourth preset temperature value; Control whether ammonia liquid enters the gas - liquid separator according to the comparison result between the liquid level detection value in the gas - liquid separator unit and a preset liquid level threshold; Control the operation of the ammonia refrigerant system according to the comparison result between the weighted average temperature value detected by the distributed temperature detection module and a preset temperature value threshold.

[0012] In an exemplary embodiment of the present disclosure, the second control rule includes: Calculate a weighted sum according to the status data and a preset weighted - sum calculation formula; When the weighted sum is within a first preset interval, generate a control instruction to adjust the operation quantity of the condensers; When the weighted sum is within a second preset interval, generate a control instruction to adjust the rotational speed of the refrigerant circulation pump.

[0013] In an exemplary embodiment of the present disclosure, the weighted - sum formula is S = a×Y + b×J + c×K + d×L Wherein, S is the weighted sum, a is the weight coefficient of the temperature value of the second refrigerant output by the evaporator unit, b is the weight coefficient of the outlet pressure value of the compressor unit, c is the weight coefficient of the liquid level value in the refrigerant storage tank unit, d is the weight coefficient of the ambient temperature value; Y is the temperature value of the second refrigerant output by the evaporator unit, J is the outlet pressure value of the compressor unit, K is the liquid level value in the refrigerant storage tank unit, and L is the ambient temperature value.

[0014] In a second aspect, an embodiment of the present disclosure provides a control method applied to an ammonia refrigerant remote integrated automatic control system disclosed in the first aspect of the present invention, including Pre - process the first data and the second data; Process the pre - processed first data and second data according to a preset first control rule or second control rule to generate the control rule instruction; The first data is the status data during the operation of the ammonia refrigerant system; The second data is the threshold data preset before the operation of the ammonia refrigerant system; Control the ammonia refrigerant system according to the control rule instruction.

[0015] In an exemplary embodiment of the present disclosure, the preprocessing includes noise filtering processing and normalization processing of the first data.

[0016] The beneficial effects of an ammonia refrigerant remote integrated automatic control system and method provided by an embodiment of the present disclosure are as follows: The data acquisition subsystem disclosed in the present invention can accurately collect the operation status data of the ammonia refrigerant system; The present disclosure remotely automates the control of the ammonia refrigerant system through the collected data, improving the convenience and timeliness of the control; The ammonia refrigerant remote integrated automatic control system of the present disclosure can perform flexible and intelligent control according to different working conditions and requirements, keep the ammonia refrigerant system in the best energy-saving operation range, minimize energy consumption, and achieve long-term energy-saving operation of the ammonia refrigerant system. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the following drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a structural diagram of an ammonia refrigerant remote integrated automatic control system provided by an embodiment of the present disclosure; Figure 2 It is a schematic diagram of an ammonia refrigerant system provided by an embodiment of the present disclosure; Figure 3 It is a schematic diagram of the intelligent control subsystem controlling the ammonia refrigerant system provided by an embodiment of the present disclosure; Figure 4 It is a flowchart of the ammonia refrigerant remote integrated automatic control system controlling the operation of the ammonia refrigerant system provided by an embodiment of the present disclosure. Detailed Embodiments

[0019] In order to enable those skilled in the art of the present technology to better understand this solution, the following will be combined with the drawings in the embodiments of this solution Figures 1-4, the technical solutions in the embodiments of this solution are clearly described. Obviously, the described embodiments are part of the embodiments of this solution, rather than all of them. Based on the embodiments in this solution, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this solution.

[0020] The terms "including" and any other variations in the specification, claims, and above-mentioned drawings of this solution mean "including but not limited to", intending to cover non-exclusive inclusion and not limited to the examples listed in the text. In addition, terms such as "first" and "second" are used to distinguish different objects, rather than to describe a specific order.

[0021] The following is a detailed description of the implementation of this disclosure in conjunction with specific drawings: Figure 1 It is a schematic structural diagram of an ammonia refrigerant remote integrated automatic control system provided for an embodiment of this disclosure. Referring to Figure 1 , this ammonia refrigerant remote integrated automatic control system includes a data acquisition subsystem and an intelligent control subsystem; where The data acquisition subsystem is used to collect the status data of the operation of the ammonia refrigerant system; The intelligent control subsystem is used to set the threshold data for the operation of the ammonia refrigerant system, and is also used to process the status data and threshold data according to the preset first control rule or second control rule to control the operation of the ammonia refrigerant system.

[0022] In this embodiment, the data acquisition subsystem adopts high-precision and anti-interference sensors and data transmission components, and is deployed at each key node of the ammonia refrigerant system through a distributed architecture, and is used to collect the status data of the operation of the ammonia refrigerant system in real time and accurately, covering key parameters such as temperature, pressure, liquid level, and flow rate, and has a data caching and preliminary verification function to ensure that data is not lost when data transmission is abnormal; The intelligent control subsystem, based on industrial automation control algorithms and artificial intelligence algorithms, sets the threshold data for the operation of the ammonia refrigerant system, and is also used to process the status data and threshold data according to the preset first control rule or second control rule to control the operation of the ammonia refrigerant system.

[0023] This disclosure can collect various status data of the operation of the ammonia refrigerant system in real time and accurately. Through the accurate acquisition and analysis of these data, the actual operation status of the ammonia refrigerant system can be clearly understood. When it is monitored that the operation parameters of a certain device deviate from the normal range, the status data and threshold data are processed according to the preset first control rule or second control rule to control the operation of the ammonia refrigerant system, avoid unnecessary energy waste, and achieve energy-saving operation.

[0024] In this embodiment, there are differences between the first control rule and the second control rule in terms of control basis, control method, control objective, etc., including I. Control basis: The first control rule makes control decisions based on the specific parameters of different units within the ammonia refrigerant remote integrated automatic control system, including the pressure value at the outlet of the compressor unit, the temperature value of the second refrigerant output by the evaporator unit, the liquid level detection value of the gas-liquid separator unit, and the weighted average temperature value detected by the distributed temperature detection module, etc. These parameters directly reflect the operating states of various parts of the ammonia refrigerant system. For example, the pressure value at the outlet of the compressor unit is used to understand the working load of the compressor and the system pressure condition, and this is used as the basis for adjusting the number of condensers started. The second control rule makes control decisions based on the weighted sum obtained by passing the state data through a preset weighted sum calculation formula. Here, the state data includes multiple aspects such as the temperature value of the second refrigerant output by the evaporator unit, the pressure value at the outlet of the compressor unit, the liquid level value in the refrigerant storage tank unit, and the ambient temperature value, etc. For example, these different types of state data are calculated to obtain the weighted sum according to a certain weight coefficient, and corresponding control instructions are generated by judging the interval where the weighted sum is located.

[0025] II. Control method: The first control rule adopts the direct control method and independently controls each specific unit in the ammonia refrigerant system. According to the comparison results of different parameters, it directly controls the operation of the condenser, the refrigerant circulation pump, the gas-liquid separator, and the ammonia refrigerant system as a whole. For example, when the temperature value of the second refrigerant output by the evaporator unit is compared with the fourth preset temperature value, the rotation speed of the refrigerant circulation pump is directly adjusted. The second control rule adopts the indirect control method. First, a comprehensive calculation is performed on multiple state data to obtain the weighted sum, and then control instructions are generated according to the interval where the weighted sum is located. This method is a control carried out after a comprehensive evaluation of the overall operating state of the system. For example, when the weighted sum is within the first preset interval, a control instruction for adjusting the number of condensers in operation is generated, rather than directly based on the parameter of a specific unit.

[0026] III. Control objective: The first control rule focuses on the refined control of each unit within the system to ensure that each unit can operate within a suitable parameter range, thereby ensuring the stable operation of the entire ammonia refrigerant system. For example, by controlling whether ammonia liquid enters the gas-liquid separator, the liquid level of the gas-liquid separator unit is maintained stable. The second control rule pays more attention to the regulation from the overall perspective of the system, comprehensively considering multiple state factors, and making the operating state of the entire system reach a better balance by adjusting the number of condensers in operation and the rotation speed of the refrigerant circulation pump, etc. For example, the number of condensers in operation is adjusted according to the weighted sum to adapt to the overall load change of the system.

[0027] In this embodiment, the intelligent control subsystem has the ability of self-learning. It can dynamically optimize the control rules and threshold settings according to the long-term collected status data and system operation feedback, so as to adapt to different working conditions and environmental changes, and improve the overall operation efficiency and stability of the system. At the same time, the intelligent control subsystem has a visual interaction interface, which is convenient for operators to monitor the system operation status in real time, adjust control parameters, and view historical data reports. It also supports multi-user permission management to ensure the security and standardization of system operations. In addition, the ammonia refrigerant remote integrated automatic control system is also equipped with a redundant power supply module, which can seamlessly switch to the standby power supply in case of main power failure to ensure the continuous and stable operation of the system. And it has a perfect communication module, supporting multiple communication protocols such as Modbus (Modicon bus, now part of Schneider Electric), OPC (OLE for Process Control), and UA (OPC Unified Architecture), etc., which can perform efficient data interaction and collaborative work with the upper monitoring system or other industrial automation devices to achieve remote monitoring and centralized management.

[0028] The data acquisition subsystem disclosed in the present invention can remotely and accurately collect the operation status data of the ammonia refrigerant system. The present invention performs automatic control on the system through the coordination of multiple control rules, enabling the system to perform flexible and intelligent control according to different working conditions and requirements, getting rid of the limitations of traditional on-site manual operation, and improving the convenience and timeliness of control. It can make decisions and adjustments quickly and accurately according to the preset rules, keep the ammonia refrigerant system in the best energy-saving operation range, avoid energy waste, and thus achieve the purpose of energy saving.

[0029] In an exemplary embodiment of the present disclosure, as Figure 2 shown, the intelligent control subsystem includes an operation station, a main station, and at least one sub-station; The operation station is used to display the status data of the ammonia refrigerant system operation, and is also used to set the threshold data, the first control rule, and the second control rule for the ammonia refrigerant system operation.

[0030] The main station is used to generate data acquisition control instructions, send the data acquisition control instructions to each sub-station, and is also used to process the status data and threshold data according to the first control rule or the second control rule, generate control rule instructions, and send the control rule instructions to each sub-station; The sub-station is used to transmit the status data of the ammonia refrigerant system operation to the main station according to the data acquisition control instructions, and is also used to control the operation of the ammonia refrigerant system according to the control rule instructions.

[0031] In this embodiment, the operation station uses a high-performance industrial computer as the hardware carrier, equipped with a powerful and user-friendly professional control software. Additionally, multiple operation stations can be configured to provide redundancy control for the ammonia refrigerant system in case of a failure of one operation station.

[0032] Operators can intuitively set parameters such as the frequency, range, and method of data collection through the graphical interface of the operation station according to the actual operation requirements and working conditions of the ammonia refrigerant system. The operation station automatically generates accurate data collection control instructions based on these settings. Meanwhile, the operation station can automatically adjust the collection strategy according to the changes in the system operation state. For example, when the system starts up, shuts down, or an abnormality occurs, it increases the collection frequency of key parameters to obtain more detailed data information.

[0033] The operation station is equipped with a high-resolution display screen to visually display the operation state data of the ammonia refrigerant system, the execution status of control instructions, and system fault information in the forms of intuitive graphs, tables, and curves, etc. Operators can remotely monitor and manage the ammonia refrigerant system through the operation station, adjust control parameters and operation modes at any time, and also view the historical operation data and statistical reports of the system, providing a strong basis for system optimization and maintenance.

[0034] The operation station supports the configuration and management of various parameters of the intelligent control subsystem, including the modification and update of the address of the sub-station, communication protocol, and control rules. Meanwhile, the operation station also has system diagnosis and troubleshooting functions, which can automatically detect hardware failures and software abnormalities in the system, and provide detailed fault information and solutions, facilitating rapid repair and recovery by maintenance personnel.

[0035] In this embodiment, the master station, as the data processing center of the intelligent control subsystem, undertakes the important tasks of data collection control and rule processing. The master station regularly generates data collection control instructions and sends these instructions to each sub-station. These instructions contain information such as the type of data to be collected and the time interval for collection. After receiving the instructions, the sub-station collects the status data of the ammonia refrigerant system as required and transmits it back to the master station. In this way, the master station realizes the real-time monitoring of the operation state of the entire system. The master station processes the status data and threshold data received from the sub-station according to the first control rule or the second control rule set by the operator at the operation station. When the status data exceeds the threshold range or meets specific rule conditions, the master station generates corresponding control rule instructions.

[0036] The master station is also equipped with data storage equipment, which can store and back up the instructions issued by the operation station and the status data uploaded by the substation in real time. The stored data can be classified and managed according to time, parameter type, etc., which is convenient for operators to query and analyze; at the same time, the master station also supports remote transmission and sharing of data, so that the superior management department can conduct real-time monitoring and decision-making.

[0037] In this embodiment, the substation collects the operating status data of the ammonia refrigerant system in real time through the connected data acquisition sensors according to the data acquisition control instructions issued by the main station, including parameters such as temperature, pressure, liquid level, and flow rate. The substation adopts an industrial controller with high reliability and strong processing capability, such as a programmable logic controller PLC; the substation performs preliminary processing and verification on the collected data, removes noise and abnormal values, and then uploads the processed data to the main station in accordance with the prescribed communication protocol and format. During the data collection process, the substation has a data caching function. When the communication is interrupted, the collected data can be temporarily saved, and the data will be resent to the main station after the communication is restored. The substation can also monitor the operating status of the control equipment in real time, and feed back the execution results to the main station so that the operation station can monitor and adjust in real time.

[0038] In an exemplary embodiment of the present disclosure, Figure 2 As shown, the ammonia refrigerant system includes an ammonia circulation subsystem and a refrigerant circulation subsystem; wherein, The ammonia circulation subsystem includes a compressor unit, a condenser unit, a thermosyphon tank, a high-pressure liquid storage barrel unit, a gas-liquid separator unit and an evaporator unit; The compressor unit is used to prepare the input ammonia gas into the first ammonia gas and transport the first ammonia gas to the condenser unit; The condenser unit includes a plurality of condensers, which are used to cool the first ammonia gas and convert it into a first ammonia liquid; and transport the first ammonia liquid to a thermosyphon tank; Thermosyphon tank is used to adjust the flow rate of the first ammonia liquid outputted by the condenser unit and to deliver the first ammonia liquid to the high-pressure liquid storage barrel unit; A high-pressure liquid storage barrel unit, used for storing the first ammonia liquid and transmitting the first ammonia liquid to the gas-liquid separator unit; A gas-liquid separator unit is used to separate the first ammonia liquid input from the high-pressure liquid storage tank from the second ammonia gas output from the evaporator unit, and to transport the first ammonia liquid to the evaporator unit and the second ammonia gas to the compressor unit; An evaporator unit is used to make the first ammonia liquid absorb the heat of the first refrigerant in the refrigerant circulation subsystem to obtain a second refrigerant, and transmit the second refrigerant to the refrigerant circulation subsystem; The refrigerant circulation subsystem includes a refrigerant storage tank unit and a refrigerant circulation pump; A refrigerant storage tank unit, used for storing refrigerant; A refrigerant circulation pump is used to transfer the first refrigerant in the refrigerant storage tank unit to the evaporator unit.

[0039] In this embodiment, the compressor unit is the power source of the ammonia circulation subsystem. Its main function is to compress the input low-pressure and low-temperature ammonia gas. Through the mechanical movement inside the compressor, the pressure and temperature of the ammonia gas are increased to prepare high-temperature and high-pressure first ammonia gas. The compressor unit usually consists of one or more compressors, and these compressors can operate in parallel or series according to the refrigeration demand of the system. The compressor unit transports the prepared first ammonia gas (high-temperature and high-pressure ammonia gas) to the condenser unit through pipelines, providing a source of high-temperature and high-pressure ammonia gas for the subsequent refrigerant cooling process.

[0040] In this embodiment, the condenser unit includes multiple condensers, which can adopt different types, such as shell-and-tube condensers, air-cooled condensers, etc., to adapt to different application scenarios and environmental conditions. A large number of heat exchange tubes are arranged inside the condenser to achieve heat exchange between ammonia gas and the cooling medium. When the high-temperature and high-pressure first ammonia gas enters the condenser, it exchanges heat with the cooling medium (such as cooling water or air), transfers the heat to the cooling medium, and thus cools the first ammonia gas and transforms it into liquid first ammonia liquid (high-pressure ammonia liquid). The condenser unit transports the cooled first ammonia liquid to the thermosyphon tank through pipelines, providing conditions for subsequent ammonia liquid regulation and storage.

[0041] In this embodiment, the main function of the thermosyphon tank is to regulate the flow rate of the first ammonia liquid output by the condenser unit. It utilizes the density difference and gravity of the ammonia liquid to achieve the natural circulation and flow rate regulation of the ammonia liquid. When the amount of ammonia liquid output by the condenser increases, the liquid level in the thermosyphon tank rises, and the outlet flow rate is automatically regulated through the liquid level control device to ensure the stable transportation of the ammonia liquid. A liquid level sensor and a regulating valve are arranged inside the thermosyphon tank, which can monitor the liquid level change in real time and precisely control the output flow rate of the ammonia liquid. This flow rate regulation method can not only ensure the stable supply of the ammonia liquid but also improve the energy utilization efficiency of the system. The regulated first ammonia liquid is transported from the thermosyphon tank to the high-pressure liquid storage barrel unit through pipelines for further storage and processing.

[0042] In this embodiment, the high-pressure liquid storage barrel unit is a sealed container used to store the first ammonia liquid transported from the thermosyphon tank. It can provide a certain storage capacity to meet the ammonia liquid demand of the system under different working conditions. A pressure sensor and a liquid level sensor are arranged inside the high-pressure liquid storage barrel unit to monitor the pressure and liquid level changes in the barrel in real time. When the pressure or liquid level exceeds the set range, the system will automatically take corresponding measures for regulation, such as opening or closing valves, adjusting the operating state of the compressor, etc., to ensure the safe operation of the liquid storage barrel. The high-pressure liquid storage barrel unit transports the stored first ammonia liquid to the gas-liquid separator unit through pipelines, providing an ammonia liquid source for the subsequent gas-liquid separation process.

[0043] In this embodiment, the main function of the gas-liquid separator unit is to separate the first ammonia liquid input from the high-pressure liquid storage tank from the second ammonia gas output from the evaporator unit. It uses the density difference between ammonia gas and ammonia liquid to separate ammonia gas and ammonia liquid by gravity sedimentation, centrifugal separation and other methods. An efficient separation device is arranged inside the gas-liquid separator unit to ensure the effective separation of ammonia gas and ammonia liquid. At the same time, the separation effect is monitored in real time by a liquid level sensor and a gas flow sensor, and the separation parameters are adjusted according to the monitoring results to ensure the stability and efficiency of the separation process. The separated first ammonia liquid is transported to the evaporator unit through a pipeline to provide ammonia liquid for the refrigeration process of the evaporator; the separated second ammonia gas is transported to the compressor unit through a pipeline for recompression to realize the recycling of ammonia.

[0044] In this embodiment, the evaporator unit is the core refrigeration component of the ammonia refrigeration system. Its main function is to use the evaporation heat absorption principle of ammonia liquid to make the first ammonia liquid absorb the heat of the first refrigerant (the refrigerant exceeding the preset refrigerant temperature) in the refrigerant circulation subsystem. Inside the evaporator, the ammonia liquid evaporates into a gaseous state under a low-pressure environment and absorbs the heat of the surrounding environment, thereby reducing the temperature of the first refrigerant and obtaining a low-temperature second refrigerant. The evaporator unit adopts an efficient heat exchange structure design, such as a fin tube heat exchanger, a plate heat exchanger, etc., to increase the heat exchange area between the ammonia liquid and the refrigerant and improve the heat exchange efficiency. At the same time, through reasonable refrigerant distribution and flow control, it is ensured that the ammonia liquid evaporates evenly in the evaporator, further improving the refrigeration effect. The evaporator unit transmits the obtained second refrigerant to the refrigerant circulation subsystem through a pipeline to provide cooling for the place or equipment that needs refrigeration.

[0045] In this embodiment, the refrigerant circulation subsystem includes a refrigerant storage tank unit and a refrigerant circulation pump, which together complete the storage and circulation of the refrigerant and provide necessary refrigerant support for the refrigeration process of the ammonia refrigeration system.

[0046] The refrigerant tank unit is a large storage container for storing refrigerant. It can provide sufficient refrigerant storage capacity to meet the refrigerant demand of the ammonia refrigeration system under different working conditions. Temperature sensors and liquid level sensors are installed inside the refrigerant tank unit to monitor the temperature and liquid level changes of the refrigerant in real time. By monitoring the temperature and liquid level, the ammonia refrigerant system can grasp the state of the refrigerant in time to ensure the storage safety of the refrigerant and the normal operation of the system. The refrigerant tank unit is connected to the refrigerant circulation pump through a pipeline to provide a stable supply of refrigerant for the refrigerant circulation. At the same time, when the refrigerant liquid level is lower than the set value, the system will automatically start the refrigerant replenishing device to replenish the refrigerant in the tank to ensure the normal operation of the system.

[0047] The main function of the refrigerant circulation pump is to transfer the first refrigerant stored in the refrigerant storage tank unit to the evaporator unit. It pumps out the refrigerant from the storage tank through mechanical power and transports it to the evaporator at a certain pressure and flow rate, providing the refrigerant circulation power for the refrigeration process of the evaporator. The refrigerant circulation pump is equipped with a flow sensor and a pressure sensor, which can monitor the changes in the flow rate and pressure of the refrigerant in real time. By controlling the flow rate and pressure, the system can adjust the circulation volume of the refrigerant according to the refrigeration demand, ensuring the stability and efficiency of the refrigeration effect. The refrigerant circulation pump adopts an efficient and reliable design, with good operating stability and reliability. At the same time, the pump body is also equipped with a complete set of protection devices, such as overload protection and overheat protection, to ensure its safe and reliable operation under various working conditions.

[0048] The present invention divides the ammonia refrigeration medium system into an ammonia circulation subsystem and a refrigerant circulation subsystem in detail, and finely designs the unit functions within each subsystem. For example, each unit (compressor unit, condenser unit, etc.) in the ammonia circulation subsystem closely cooperates to achieve the transformation and recycling of ammonia gas to ammonia liquid; the refrigerant circulation subsystem is responsible for the storage and transportation of the refrigerant. This fine design optimizes the refrigeration process and improves the refrigeration efficiency.

[0049] In an exemplary embodiment of the present disclosure, the data acquisition subsystem includes: A first temperature sensor, arranged at the outlet position of the compressor unit, for detecting the temperature value of the first ammonia gas output by the compressor; A second temperature sensor, arranged at the inlet position of the compressor unit, for detecting the temperature value of the ammonia gas inhaled into the compressor; A third temperature sensor, arranged at the inlet position of the evaporator unit, for detecting the temperature value of the first refrigerant input to the evaporator unit; A fourth temperature sensor, arranged at the outlet position of the evaporator unit, for detecting the temperature value of the second refrigerant output by the evaporator unit; A distributed temperature detection module, arranged inside the refrigerant storage tank unit, for detecting the temperature value of the refrigerant inside the refrigerant storage tank unit; wherein, the distributed temperature detection module includes a fifth temperature sensor, a sixth temperature sensor, a seventh temperature sensor, and an eighth temperature sensor; A ninth temperature sensor, arranged inside the high-pressure liquid storage barrel, for detecting the temperature value of the first ammonia liquid inside the high-pressure liquid storage barrel; A first pressure sensor, arranged at the inlet position of the compressor unit, for detecting the pressure value at the inlet of the compressor unit; A second pressure sensor, arranged at the outlet position of the compressor unit, for detecting the pressure value at the outlet of the compressor unit; A third pressure sensor, arranged inside the high-pressure liquid storage tank unit, for detecting the pressure value of the first ammonia liquid inside the high-pressure liquid storage tank unit; The first liquid level sensor is used to detect the liquid level value in the high-pressure liquid storage tank unit; The second liquid level sensor is used to detect the liquid level value in the refrigerant storage tank unit; The flow sensor is used to detect the flow rate of the refrigerant output by the variable-frequency refrigerant circulation pump; The ambient temperature sensor is used to detect the ambient temperature value of the ammonia refrigerant system.

[0050] In this embodiment, multiple temperature sensors are distributed at key positions such as the compressor unit, the evaporator unit, and the high-pressure liquid storage tank, and can obtain the temperature data of each part in real time and accurately. Taking the compressor unit as an example, the first temperature sensor monitors the outlet ammonia temperature, and the second temperature sensor monitors the inlet ammonia temperature. By precisely controlling these two temperatures, it can be timely discovered whether the compressor is working abnormally. If the outlet temperature is too high, it may mean problems such as too large a compression ratio of the compressor or a cooling system failure. At this time, the system can adjust the operating parameters in time according to these data or issue an alarm to avoid equipment damage caused by abnormal temperature and ensure the stable operation of the compressor and even the entire ammonia refrigerant system.

[0051] The pressure sensors are distributed at the inlet and outlet of the compressor unit and inside the high-pressure liquid storage tank unit to monitor the pressure in the system in real time. The pressure values at the inlet and outlet of the compressor directly affect its working efficiency and safety. The first pressure sensor and the second pressure sensor can timely feedback the pressure change situation. When the outlet pressure is too high, the system can adjust the operating state of the condenser to reduce the pressure and prevent equipment failures or safety accidents caused by abnormal pressure. The monitoring of the ammonia liquid pressure in the high-pressure liquid storage tank by the third pressure sensor can ensure the safety of ammonia liquid storage and avoid serious consequences such as the rupture of the liquid storage tank due to excessive pressure.

[0052] The first liquid level sensor and the second liquid level sensor respectively detect the liquid levels in the high-pressure liquid storage tank unit and the refrigerant storage tank unit. By accurately mastering the liquid level information, the system can reasonably control the replenishment and discharge of ammonia liquid and refrigerant. When the liquid level in the high-pressure liquid storage tank is too low, the system can timely start the ammonia liquid replenishment device to prevent the refrigeration effect from being affected due to insufficient ammonia liquid; when the liquid level in the refrigerant storage tank is abnormal, corresponding measures can also be taken in time to ensure the normal circulation of the refrigerant and the stable operation of the system.

[0053] The third temperature sensor and the fourth temperature sensor respectively monitor the temperatures of the refrigerant at the inlet and outlet of the evaporator unit. By comparing the inlet and outlet temperatures, the system can understand the refrigeration effect of the evaporator. The intelligent control subsystem adjusts the rotation speed of the refrigerant circulation pump according to these temperature data, so that the refrigerant can perform heat exchange more efficiently in the evaporator, thereby improving the refrigeration efficiency and reducing energy consumption. For example, when it is detected that the temperature of the refrigerant at the outlet of the evaporator is higher than the set value, the rotation speed of the refrigerant circulation pump can be appropriately increased to increase the refrigerant flow rate and enhance the refrigeration effect.

[0054] The distributed temperature detection module includes the fifth temperature sensor, the sixth temperature sensor, the seventh temperature sensor, and the eighth temperature sensor. These four temperature sensors are distributed within the refrigerant storage tank unit to comprehensively detect the temperature of the refrigerant in the refrigerant storage tank unit, and can detect whether there is a temperature stratification phenomenon in the refrigerant. When a too large temperature difference is detected, the system can take corresponding measures, such as starting the stirring device or adjusting the refrigerant circulation mode, to eliminate the temperature difference of the refrigerant, enabling the refrigerant to participate in the refrigeration cycle more evenly and improving the energy utilization efficiency of the entire system.

[0055] When the ninth temperature sensor detects that the temperature of the first ammonia liquid in the high-pressure liquid storage barrel rises abnormally, or the third pressure sensor detects that the pressure in the liquid storage barrel is too high, the system will trigger an audible and visual alarm to remind the operator to take measures in time to avoid accidents.

[0056] As the operating conditions of the system change, the data collected by each sensor will also change accordingly. The intelligent control subsystem can dynamically adjust the operating parameters of the system according to the real-time data, so that the system is always in the best operating state. For example, according to the ambient temperature change detected by the ambient temperature sensor, the system can automatically adjust the number of operating condensers or the rotation speed of the refrigerant circulation pump to adapt to different environmental conditions.

[0057] In an exemplary embodiment of the present disclosure, the operation station includes: A condenser priority control module, which is used to accumulate the operating time of each condenser in the condenser unit, generate a priority queue, and start the condenser with the shortest operating time first; A hysteresis pressure control module, which is used to start condensers one by one until the pressure value at the output port of the compressor unit returns within the first preset pressure value threshold range when the time that the pressure value at the output port of the compressor unit is greater than the first preset pressure value threshold range lasts for more than the preset time; A refrigerant stratification temperature control module, which is used to control the operation of the ammonia refrigeration system to eliminate the temperature difference of the refrigerant in the refrigerant storage tank unit when the weighted average temperature value detected by the distributed temperature detection module is greater than the preset temperature value threshold; A dual-threshold alarm module, which is used to trigger an audible and visual alarm and issue an emergency shutdown instruction when it detects that the temperature value of the first ammonia liquid in the high-pressure liquid storage barrel unit is greater than the second preset temperature value and / or the pressure of the first ammonia liquid is greater than the second preset pressure value; A compressor low-temperature protection module, which is used to stop inhaling ammonia when it detects that the temperature value at the inlet of the compressor unit is lower than the third preset temperature value.

[0058] In this embodiment, the condenser priority control module has an accurate time recording function, which can continuously and accurately accumulate the running time of each condenser in the condenser unit. After the system starts, it will initiate an independent timing task for each condenser, record the running duration of each start-stop cycle, and accumulate these durations to form the total running time data of each condenser. Based on the accumulated running time data, the module generates a priority queue in ascending order of running time. During this process, the module sorts the running times of all condensers and assigns corresponding priority numbers to each condenser. The condenser with the shortest running time is placed at the front of the queue and has the highest priority. When a condenser needs to be started, the condenser priority control module will preferentially select the condenser at the front of the priority queue, i.e., the condenser with the shortest running time. This startup strategy helps to balance the usage frequency of each condenser, prevent some condensers from being damaged prematurely due to overuse, and also improve the service life and operating efficiency of the entire condenser unit. In addition, the module also considers the current state of the condenser (such as whether it is faulty, under maintenance, etc.) to ensure that the selected condenser can be put into operation normally. As the system runs, the running times of each condenser will change continuously, and the priority queue will be updated in real time. The module will regularly re-sort the priority queue to ensure that the condenser with the shortest running time can be accurately selected for startup at any time, achieving dynamic optimization control.

[0059] The hysteresis pressure control module will continuously monitor the pressure value at the outlet of the compressor unit and compare it with the pre-set first preset pressure value threshold range. This threshold range is determined based on the design requirements and actual operating experience of the ammonia refrigeration medium system, and it represents the normal operating range of the pressure at the compressor outlet. When the pressure value at the outlet of the compressor unit is detected to be greater than the first preset pressure value threshold range, the module will activate the timing function to record the duration for which the pressure exceeds the threshold range. Only when this duration exceeds the preset time will the module consider that the abnormal pressure situation needs to be addressed. The setting of the preset time can avoid unnecessary condenser startups caused by short-term pressure fluctuations, improving the stability and reliability of the system. Once the abnormal pressure duration exceeds the preset time, the hysteresis pressure control module will start the condensers one by one in a certain order. The startup order can be set according to factors such as the priority and performance of the condensers. After starting each condenser, the module will continue to monitor the pressure value at the outlet of the compressor unit to observe whether the pressure returns to the first preset pressure value threshold range. If the pressure still exceeds the threshold range, the module will continue to start the next condenser until the pressure returns to normal. When the pressure value at the outlet of the compressor unit returns to the first preset pressure value threshold range, the module will not immediately stop the operation of the condensers. To avoid a rapid rise in pressure again, the module will maintain the current operating state of the condensers for a period of time to ensure pressure stability. During this process, the module will continuously monitor the pressure changes and adjust the number of operating condensers in a timely manner according to the actual situation.

[0060] The refrigerant stratification temperature control module receives the temperature data at different positions in the refrigerant storage tank unit transmitted by the distributed temperature detection module, and performs weighted average calculation on these data. The calculation method of the weighted average is set according to the positions and importance of each temperature sensor to more accurately reflect the overall temperature of the refrigerant in the refrigerant storage tank. The calculated weighted average temperature value is compared with the preset temperature value threshold. The preset temperature value threshold is determined according to the refrigeration requirements of the ammonia refrigerant system and the characteristics of the refrigerant, and it represents a reasonable range of the refrigerant temperature in the refrigerant storage tank. If the weighted average temperature value is greater than the preset temperature value threshold, the module will judge that there is a problem of excessive refrigerant temperature difference in the refrigerant storage tank unit, that is, refrigerant stratification may occur. When excessive refrigerant temperature difference is detected, the refrigerant stratification temperature control module will take a series of measures to eliminate the temperature difference. These measures include but are not limited to starting the refrigerant stirring device to fully mix the refrigerant in the storage tank; adjusting the operating parameters of the refrigerant circulation pump to increase the circulation flow of the refrigerant and promote the heat exchange of the refrigerant; or adjusting the operating state of the evaporator unit to change the refrigeration effect of the refrigerant, etc. The module will comprehensively consider the actual situation and select the most appropriate control strategy to eliminate the refrigerant temperature difference as soon as possible and ensure the uniformity of the refrigeration effect. After taking control measures, the module will continuously monitor the temperature data transmitted by the distributed temperature detection module to evaluate the effect of the control measures. If the refrigerant temperature difference still has not been effectively improved, the module will further adjust the control strategy and increase the control intensity; if the temperature difference has returned to the reasonable range, the module will gradually restore the normal operating state of the system to avoid energy waste caused by over-control.

[0061] The dual-threshold alarm module continuously monitors the temperature and pressure values of the first ammonia liquid in the high-pressure liquid storage tank unit, and compares them with the pre-set second preset temperature value and second preset pressure value respectively. These two thresholds are determined based on the physical properties of the ammonia liquid and the safety requirements of the system. Once the temperature or pressure of the ammonia liquid exceeds these thresholds, the system may face safety risks. When it is detected that the temperature value of the first ammonia liquid in the high-pressure liquid storage tank unit is greater than the second preset temperature value and / or the pressure value of the first ammonia liquid is greater than the second preset pressure value, the dual-threshold alarm module immediately triggers the audible and visual alarm device. The audible and visual alarm signal alerts the operator to the abnormal situation of the system through flashing lights and loud sounds, ensuring that the operator can detect and handle problems in a timely manner. While triggering the audible and visual alarm, the module quickly issues an emergency shutdown command. This command is transmitted to various key devices of the ammonia refrigeration medium system, such as the compressor unit, the refrigerant circulation pump, etc., causing these devices to stop operating immediately to prevent the further expansion of the accident. At the same time, the module records information such as the time of the abnormality occurrence and the specific parameter values, providing a basis for subsequent fault troubleshooting and analysis. After issuing the emergency shutdown command, the module enters the safety recovery state. After the operator eliminates the fault and confirms the safety of the system, the system can be reset through the operation station. The module re-checks the various parameters of the system and only allows the system to restart after ensuring that all parameters have returned to the normal range.

[0062] The compressor low-temperature protection module continuously monitors the inlet temperature value of the compressor unit and compares it with the pre-set third preset temperature value. The third preset temperature value is determined based on the operating characteristics of the compressor and the physical properties of the ammonia liquid. When the inlet temperature is lower than this threshold, the compressor sucking ammonia gas may cause a liquid hammer phenomenon, damaging the internal components of the compressor. Once it is detected that the inlet temperature value of the compressor unit is lower than the third preset temperature value, the compressor low-temperature protection module immediately triggers a protection action to stop the compressor from sucking ammonia gas. The specific implementation method can be to close the suction valve of the compressor to prevent the ammonia liquid from entering the compressor. At the same time, the module records the occurrence time of the low-temperature event and related parameters for subsequent analysis. After stopping sucking ammonia gas, the module continuously monitors the inlet temperature value of the compressor unit. When the temperature gradually rises and returns to the safe range, the module does not immediately resume the normal operation of the compressor. To ensure the safety of the compressor, the module sets a delay time. After the delay time ends, the suction valve is gradually opened to allow the compressor to start sucking ammonia liquid again and resume normal operation. At the same time, the module analyzes the temperature change trend to determine whether there is a risk of low temperature occurring again, and adjusts the operating parameters of the system if necessary to avoid similar situations from happening again.

[0063] In an exemplary embodiment of the present disclosure, the first control rule includes: Adjust the starting quantity of the condensers in the condenser unit according to the pressure value at the outlet of the compressor unit; Adjust the rotational speed of the refrigerant circulation pump according to the comparison result between the temperature value of the second refrigerant output by the evaporator unit and the fourth preset temperature value; Control whether ammonia liquid enters the gas-liquid separator according to the comparison result between the liquid level detection value in the gas-liquid separator unit and the preset liquid level threshold; Control the operation of the ammonia refrigeration system according to the comparison result between the weighted average temperature value detected by the distributed temperature detection module and the preset temperature value threshold.

[0064] In an exemplary embodiment of the present disclosure, the second control rule includes Calculate the weighted sum according to the status data and the preset weighted sum calculation formula; When the weighted sum is within the first preset interval, generate a control instruction to adjust the operating quantity of the condensers; When the weighted sum is within the second preset interval, generate a control instruction to adjust the rotational speed of the refrigerant circulation pump.

[0065] In this embodiment, the intelligent control subsystem will monitor the pressure value at the outlet of the compressor unit in real time and accurately. According to the design requirements of the system and actual operation experience, the pressure range is divided into multiple intervals, and each interval corresponds to a different condenser starting quantity strategy. For example, when the pressure is in a lower interval, it indicates that the refrigeration load of the system is small, and only a small number of condensers need to be started to meet the demand; as the pressure rises into the medium interval, appropriately increase the starting quantity of the condensers to enhance the cooling capacity; when the pressure reaches a higher interval, start more condensers or even all condensers to ensure that the high-temperature and high-pressure ammonia gas output by the compressor can be cooled in time and effectively. After adjusting the starting quantity of the condensers, the system will continuously monitor the pressure value at the outlet of the compressor unit to evaluate the adjustment effect. If the pressure does not change as expected, for example, the pressure is still too high or too low, the system will further analyze the reason and readjust the starting quantity of the condensers, forming a closed-loop feedback adjustment mechanism to continuously optimize the operating state of the system.

[0066] In this embodiment, the refrigerant circulation pump speed is adjusted according to the comparison result between the second refrigerant temperature value output by the evaporator unit and the fourth preset temperature value. Temperature comparison and speed adjustment logic: The intelligent control subsystem compares the second refrigerant temperature value output by the evaporator unit with the pre-set fourth preset temperature value in real time. When the second refrigerant temperature value is higher than the fourth preset temperature value, it indicates that the refrigeration effect of the evaporator does not meet the expectation. At this time, the system will appropriately increase the speed of the refrigerant circulation pump to increase the circulation flow of the refrigerant in the evaporator, thereby enhancing the heat exchange efficiency between the refrigerant and the ammonia liquid and reducing the second refrigerant temperature. Conversely, when the second refrigerant temperature value is lower than the fourth preset temperature value, the system will reduce the speed of the refrigerant circulation pump to reduce the refrigerant flow and avoid energy waste caused by excessive refrigeration. To achieve precise temperature control and avoid overly frequent speed adjustment, the system will determine an appropriate speed adjustment amplitude according to the difference between the second refrigerant temperature value and the fourth preset temperature value. When the difference is large, a large adjustment amplitude is used to quickly approach the target temperature; when the difference is small, a small adjustment amplitude is used for fine adjustment to ensure that the second refrigerant temperature can be stabilized near the fourth preset temperature value. At the same time, the system will strictly control the adjustment accuracy of the refrigerant circulation pump speed to avoid excessive temperature fluctuations caused by adjustment errors. When adjusting the speed of the refrigerant circulation pump, the system will also comprehensively consider other factors, such as the ambient temperature and the operating state of the compressor. For example, when the ambient temperature is high, the heat load of the evaporator increases, and it may be necessary to appropriately increase the speed of the refrigerant circulation pump to ensure the refrigeration effect; when the compressor runs unstably, the speed of the refrigerant circulation pump will also be adjusted according to the actual situation to ensure the coordination and stability of the entire system.

[0067] In this embodiment, whether ammonia liquid enters the gas-liquid separator is controlled according to the comparison result between the liquid level detection value in the gas-liquid separator unit and the preset liquid level threshold. Threshold setting: The liquid level sensor installed in the gas-liquid separator unit is used to obtain the liquid level detection value in the gas-liquid separator in real time. The preset liquid level threshold includes an upper threshold and a lower threshold, which are determined according to factors such as the design capacity of the gas-liquid separator, the system operation requirements, and the stability of the ammonia liquid circulation. The upper threshold is used to prevent the liquid level in the gas-liquid separator from being too high, causing ammonia gas to carry ammonia liquid into the compressor and resulting in liquid hammer damage; the lower threshold is used to ensure that there is enough ammonia liquid in the gas-liquid separator for gas-liquid separation to ensure the separation effect.

[0068] In this embodiment, the distributed temperature detection module collects temperature data at multiple positions within the refrigerant storage tank unit. The intelligent control subsystem performs weighted average calculation on these data to more accurately reflect the overall temperature of the refrigerant in the storage tank. The calculation method of the weighted average is set according to the positions and importance of each temperature sensor. For example, the data weights of the sensors near the refrigerant inlet and outlet may be relatively large. The calculated weighted average temperature value is compared with the preset temperature value threshold. When the weighted average temperature value is greater than the preset temperature value threshold, it indicates that there may be refrigerant stratification in the storage tank, resulting in uneven temperature. At this time, the system will activate corresponding control strategies to eliminate the temperature difference. These strategies include but are not limited to starting the refrigerant stirring device to fully mix the refrigerant in the storage tank; adjusting the operating parameters of the refrigerant circulation pump to increase the circulation flow rate of the refrigerant and promote heat exchange of the refrigerant; or adjusting the operating state of the evaporator unit to change the refrigeration effect of the refrigerant, etc. When the weighted average temperature value is lower than the preset temperature value threshold, the system will appropriately reduce the refrigeration intensity according to the actual situation to reduce energy consumption. After implementing the control strategy, the system continuously monitors the temperature data of the distributed temperature detection module to evaluate the control effect. If the temperature difference has not been effectively improved, the system will further analyze the reasons, adjust the control strategy, and increase the control intensity; if the temperature difference has returned to a reasonable range, the system will gradually return to the normal operating state, summarize and analyze the control process, continuously optimize the control strategy, and improve the accuracy and efficiency of the system's control of the refrigerant temperature.

[0069] In this embodiment, when the calculated weighted sum is within the first preset interval, it indicates that the system may face situations such as a large refrigeration load and an increased heat dissipation requirement. At this time, the system will generate a control instruction to adjust the number of operating condensers. When the weighted sum is within the second preset interval, it means that the refrigerant circulation state of the system may need to be adjusted. At this time, the system will generate a control instruction to adjust the rotational speed of the refrigerant circulation pump. If the weighted sum shows that the refrigeration effect of the evaporator is not ideal or the heat exchange efficiency of the refrigerant needs to be improved, the system will appropriately increase the rotational speed of the refrigerant circulation pump, increase the circulation flow rate of the refrigerant in the evaporator, enhance the heat exchange between the refrigerant and the ammonia liquid, and enable the temperature of the secondary refrigerant to reach the target value faster. Conversely, if the weighted sum shows that there is over-refrigeration in the system or the refrigerant circulation is too fast, resulting in energy waste, the system will reduce the rotational speed of the refrigerant circulation pump and decrease the refrigerant flow rate to achieve energy-saving operation. When adjusting the rotational speed, the adjustment range of the rotational speed will be precisely controlled according to the difference between the weighted sum and the preset target value to ensure a smooth transition of the refrigerant circulation state and the stable operation of the system. In addition to the first preset interval and the second preset interval, other preset intervals can also be reserved according to the actual operating conditions of the system and the possible working conditions, and corresponding control strategies can be formulated for each interval. For example, when the weighted sum is within a certain lower interval, it may indicate that the refrigeration load of the system is extremely low. At this time, the operating power of the compressor can be considered to be reduced or some non-critical equipment can be stopped to further reduce energy consumption. When the weighted sum is within a certain higher interval and exceeds the safety range, the system may trigger emergency protection measures, such as stopping the operation of the entire system and issuing an alarm to ensure the safety of the equipment and personnel. The generated control instructions will be accurately sent to each sub-station through the master station of the intelligent control subsystem. After receiving the instructions, the sub-station will quickly control the corresponding equipment to execute the operations. For example, the instruction to increase the number of operating condensers will cause the corresponding condenser to start running, and the instruction to adjust the rotational speed of the refrigerant circulation pump will cause the motor of the pump to run at the set rotational speed. During the execution of the instructions by the equipment, the execution status information will be fed back in real time, such as whether the condenser has been successfully started and the actual rotational speed of the refrigerant circulation pump, so that the system can monitor in real time. After the control instructions have been executed for a period of time, the system will collect relevant status data again, recalculate the weighted sum, and compare it with the preset interval to evaluate the execution effect of the control instructions. If the weighted sum still deviates from the target interval, it means that the current control strategy may not be effective enough. The system will dynamically adjust the control instructions according to the actual situation, such as further increasing or decreasing the number of operating condensers and fine-tuning the rotational speed of the refrigerant circulation pump again. Through this continuous feedback adjustment mechanism, the system can adapt to different operating conditions and always maintain the best operating state.

[0070] In an exemplary embodiment of the present disclosure, the weighted sum formula is S = a×Y + b×J + c×K + d×L Among them, S is the weighted sum, a is the weight coefficient of the temperature value of the second refrigerant output by the evaporator unit, b is the weight coefficient of the outlet pressure value of the compressor unit, c is the weight coefficient of the liquid level value in the refrigerant storage tank unit, and d is the weight coefficient of the ambient temperature value; Y is the temperature value of the second refrigerant output by the evaporator unit, J is the outlet pressure value of the compressor unit, K is the liquid level value in the refrigerant storage tank unit, L is the ambient temperature value, and a + b + c + d = 1.

[0071] In this embodiment, by collecting the historical operation data of the ammonia refrigeration system, machine learning algorithms (such as genetic algorithms, particle swarm optimization algorithms, etc.) can be trained. The weight coefficients of the above weighted sum formula can be optimized and adjusted through the trained machine learning algorithms and the operation data of the current ammonia refrigeration system. According to different working conditions (such as day / night, different seasons, different refrigeration loads, etc.), the weight coefficients can be adjusted intelligently so that the weighted sum can more accurately reflect the actual operation state of the system. For example, in summer with high temperature, the ambient temperature value L has a greater impact on the system operation, and the weight coefficient d can be increased; while in winter, the value of a can be increased for the temperature value Y of the second refrigerant output by the evaporator unit.

[0072] In an exemplary embodiment of the present disclosure, the second control rule further includes: When the weighted sum is within the first preset interval, a PID controller is used to control the ammonia refrigeration system; When the weighted sum is within the second preset interval, a neural network is used to predict and control the ammonia refrigeration system.

[0073] In this embodiment, when the weighted sum is within the first preset interval, a control instruction for adjusting the number of condensers in operation is generated. At this time, the specific number of additional condensers can be determined by further combining the energy efficiency ratio of the condensers and the current system load situation; by establishing an energy efficiency model of the condensers, the energy efficiency performance of each condenser can be predicted according to different operating conditions, and the condensers with high energy efficiency are preferentially selected to be put into operation. At the same time, after increasing the number of condensers in operation, the changes in the operation parameters of the system are monitored in real time, and the control effect is evaluated. If the weighted sum fails to be effectively reduced to the appropriate interval, the number of condensers in operation can be dynamically adjusted or other auxiliary control measures can be taken, such as adjusting the suction pressure of the compressor.

[0074] When the weighted sum is within the second preset range, a control instruction for adjusting the rotational speed of the refrigerant circulation pump is generated. In addition to the conventional rotational speed adjustment, predictive adjustment can be performed in combination with the changing trend of the refrigeration demand of the ammonia refrigerant system. By using methods such as deep neural networks or long short-term memory networks, the change in refrigeration demand within a certain period in the future is predicted, and the rotational speed of the refrigerant circulation pump is adjusted in advance to avoid temperature fluctuations caused by lag adjustment. In addition, during the process of adjusting the rotational speed, in addition to adjusting the refrigerant circulation pump, the operating states of other devices (such as evaporators, condensers, etc.) will also be adjusted according to the collaborative working relationship with other devices to ensure the operational coordination of the entire system.

[0075] Or, based on predicting the future system state by using methods such as deep neural networks or long short-term memory networks, the optimal control strategy is calculated by optimizing the objective function to achieve more precise and efficient control of the ammonia refrigerant system.

[0076] In an exemplary embodiment of the present disclosure, an ammonia refrigerant remote integrated automatic control system further includes: A fault diagnosis module, which is used to analyze the acquired state data patterns according to the constructed machine learning algorithm. For example, according to data such as the temperature, pressure, and operating duration of the compressor, possible faults of the compressor, such as wear and valve leakage, are predicted in advance; for the condenser, according to data such as its inlet and outlet temperatures, pressure difference, and operating time, it is judged whether there are problems such as fouling and blockage. For key devices in the ammonia refrigerant system, such as the compressor unit, condenser unit, etc., a fault code system is set. When abnormal state data is detected, the system automatically generates the corresponding fault code, and displays the detailed fault description and possible solutions through the operation station.

[0077] In an exemplary embodiment of the present disclosure, an ammonia refrigerant remote integrated automatic control system further includes: an energy management module, which is used to calculate the energy consumption data of each subsystem and device of the ammonia refrigerant system, and is also used to formulate an energy optimization strategy based on the energy consumption data and the operating state of the ammonia refrigerant system.

[0078] For example, by collecting the power data of the compressor, the power consumption of the refrigerant circulation pump, etc., the total energy consumption of the system is statistically calculated in real time. According to factors such as the ambient temperature and refrigeration demand in different time periods, the number of operating condensers and the rotational speed of the refrigerant circulation pump are intelligently adjusted to minimize the system energy consumption and improve the energy utilization efficiency on the premise of meeting the refrigeration requirements.

[0079] In a second aspect, the embodiments of the present disclosure provide a control method applied to an ammonia refrigerant remote integrated automatic control system disclosed in the first aspect of the present invention, including Preprocessing the first data and the second data; Process the preprocessed first data and second data according to a preset first control rule or second control rule to generate a control rule instruction; The first data is the state data during the operation of the ammonia refrigerant system; The second data is the threshold data preset before the operation of the ammonia refrigerant system; Control the ammonia refrigerant system according to the control rule instruction.

[0080] In an exemplary embodiment of the present disclosure, the preprocessing includes noise filtering processing and normalization processing on the first data.

[0081] In this embodiment, during the operation of the ammonia refrigerant system, the acquisition of the first data (i.e., the state data during the operation of the ammonia refrigerant system) is interfered by various factors, thus introducing noise. These noise sources are extensive. For example, the accuracy error of the sensor itself, electrical interference, environmental factors (such as temperature and humidity changes), and mechanical vibrations during the system operation, etc. The existence of noise will cause the collected data to deviate from the true value, affect the subsequent analysis and processing results of the data, and may further lead to inaccurate control rule instructions, affecting the normal operation of the ammonia refrigerant system. In practical applications, it is necessary to select mean filtering, median filtering, or Kalman filtering to filter the collected data. At the same time, the filtering parameters can also be optimized and adjusted to achieve the best filtering effect. For example, for mean filtering, it is necessary to reasonably select the size of the time window; for Kalman filtering, it is necessary to accurately estimate the noise covariance matrix of the system. In addition, a multi-stage filtering method can also be adopted. First, use a simple filtering method for preliminary processing, and then use a more advanced filtering method for fine filtering to further improve the quality of the data. After the normalization processing of the first data, these data can be more conveniently applied to the calculation of the preset first control rule or second control rule. At the same time, during the operation of the system, since the distribution of the data may change, it is necessary to regularly update and adjust the normalization parameters to ensure the effectiveness and accuracy of the normalization.

[0082] The present invention constructs a remote integrated automatic control system for ammonia refrigerant covering a data acquisition subsystem and an intelligent control subsystem, realizes remote acquisition of operation status data of the ammonia refrigerant system, and remotely automates the control of the system according to preset rules, getting rid of the limitations of traditional on-site manual operation and improving the convenience and timeliness of control. The first control rule and the second control rule work together to flexibly adjust the system operation according to different working conditions. For example, under different ambient temperatures and load conditions, by adjusting the number of condensers started and the rotational speed of the refrigerant circulation pump, the system can always maintain efficient operation. Compared with a single control rule, the system performance can be improved by 20%-30% under complex working conditions. The intelligent control strategies of each functional module in the operation station not only protect the equipment but also optimize the system operation. For example, the condenser priority control module extends the equipment life and reduces the performance degradation caused by equipment failures; the hysteresis pressure control module maintains pressure stability and ensures the efficient operation of the system. Taken together, the long-term stable operation performance of the system can be improved by 15%-20%.

[0083] In one embodiment, a remote integrated automatic control system for ammonia refrigerant (alcohol water) includes: a compressor unit, a condenser unit, a high-pressure liquid storage tank, a gas-liquid separator, an evaporator, a refrigerant storage tank, an intelligent control subsystem, and a data acquisition subsystem.

[0084] The compressor unit includes a compression motor, a first pressure sensor is provided at the inlet, and a second temperature sensor. A second pressure sensor and a first temperature sensor are provided at the outlet.

[0085] The condenser unit includes 3 small condensers (numbered condenser No. 1, condenser No. 2, and condenser No. 3) operating in parallel. Each condenser includes 1 condensing fan and 1 condensing water pump, the first condensing fan, the second condensing fan, the third condensing fan, the first condensing water pump, the second condensing water pump, and the third condensing water pump. A liquid level switch is provided for each condenser to interlock and control the start and stop operation of the condensing water pump. The first liquid level switch, the second liquid level switch, and the third liquid level switch. The optimized design includes 1 thermosyphon tank, and a thermosyphon tank is provided between the condenser and the high-pressure liquid storage tank to improve the condensation efficiency.

[0086] A ninth temperature sensor, a third pressure sensor, and a first liquid level sensor are provided in the high-pressure liquid storage tank; The gas-liquid separator is provided with a first ammonia liquid inlet automatic control valve and a second ammonia liquid inlet automatic control valve, and the fourth liquid level switch and the fifth liquid level switch interlock to control the first ammonia liquid inlet automatic control valve and the second ammonia liquid inlet automatic control valve.

[0087] A refrigerant inlet (third) temperature sensor and a refrigerant outlet (fourth) temperature sensor are provided in the evaporator.

[0088] The refrigerant storage tank stores a refrigerating refrigerant (-4°C alcohol water) at a suitable temperature, and uses the heat exchange process of the evaporator to produce alcohol water at -4°C, with a dedicated refrigerant storage tank. A first refrigerant circulation pump and a second refrigerant circulation pump are arranged in the refrigerant storage tank, and the second refrigerant circulation pump is used as a standby; a distributed temperature detection module including a fifth temperature sensor, a sixth temperature sensor, a seventh temperature sensor and an eighth temperature sensor is also arranged. The four temperature sensors are evenly distributed on the tank body of the refrigerant storage tank from top to bottom; for example, the installation position of the fifth temperature sensor is 20 cm above the outlet pipe of the refrigerant on the refrigerant storage tank; the installation position of the eighth temperature sensor is 20 cm above the bottom of the refrigerant tank of the refrigerant storage tank; a second liquid level sensor is also arranged, installed at the bottom of the tank body, used to monitor the liquid level in the refrigerant storage tank, and used for interlocking control of the start and stop of the refrigerant circulation pump. The refrigerant storage tank unit also includes a first flow sensor, installed on the outlet pipe of the refrigerant circulation pump, used for interlocking control of the output refrigerant flow rate of the refrigerant circulation pump.

[0089] The ammonia refrigerant remote integrated automatic control system includes a PLC master station (power supply, controller CPU, PLC master station cabinet), a PLC slave station (PLC input / output module, PLC slave station cabinet), industrial field bus equipment, 2 operation stations (redundant control), an electrical control cabinet, an inverter, electrical installation materials, etc. The operation stations are installed in the central control room for the operator to centrally operate and monitor the system operation. The PLC master station cabinet is installed in the central control room. The PLC slave station cabinet is installed at the equipment site. The PLC slave station includes a PLC slave station cabinet and a PLC input / output module; temperature sensors, pressure liquid level sensors, flow liquid level sensors, liquid level sensors, liquid level switches, ambient temperature sensors, automatic valves, condenser water pumps, and refrigerant circulation pumps are connected to the PLC slave station through cables. The PLC input / output module automatically collects input signals and outputs control signals. The PLC can provide various communication interfaces to facilitate communication with the main control system and each auxiliary system; the operation stations are connected to the PLC through the industrial field bus to control and monitor the production process in real time, realizing the remote integrated automatic control of the ammonia refrigerant. The electrical control cabinet is installed in the room of the control center, and low-voltage control devices and inverters are installed in the electrical control cabinet. The on-site motors and pumps are connected to the low-voltage control devices and inverters in the control cabinet through cables.

[0090] In this embodiment, the ammonia refrigerant system further includes an automatic venting device. During the ammonia refrigeration cycle, the non-recyclable ammonia and air mixture gas generated exists in the evaporator and pipelines, which affects the refrigeration effect and needs to be vented in time. The automatic venting unit discharges these gases regularly according to the setting.

[0091] In one embodiment, an ammonia refrigerant remote integrated automatic control method includes: The first step, the ammonia circulation process: High-pressure liquid ammonia is stored in a high-pressure liquid storage tank. During this process, the liquid ammonia remains in a high-pressure environment and hardly changes its form. Among them, the liquid ammonia has a temperature of -10°C to 20°C and a pressure of 1.5 to 3.5 MPa.

[0092] The high-pressure ammonia liquid flows from the high-pressure liquid storage tank into the gas-liquid separator. When the liquid ammonia enters the gas-liquid separator, part of the liquid ammonia evaporates into gas, and in addition, the gaseous ammonia after evaporation in the evaporator returns to the gas-liquid separator, thus generating a gas-liquid mixture, with ammonia gas at the upper part and ammonia liquid at the lower part. Liquid ammonia (bottom), gaseous ammonia (top), temperature -10°C to 20°C, pressure 1.5 to 3.5 MPa. The ammonia liquid flows from the gas-liquid separator into the evaporator (plate heat exchanger). After heat exchange (the liquid ammonia absorbs the heat of the refrigerant), it evaporates into ammonia gas and returns to the gas-liquid separator. Gaseous ammonia: temperature -10°C to 10°C, pressure 0.1 to 1.0 MPa. The ammonia gas is inhaled into the ammonia compressor through the gas-liquid separator. In the compressor, the ammonia gas is compressed into high-pressure and high-temperature gaseous ammonia. The compressed high-pressure and high-temperature ammonia gas flows into the condenser. Gaseous ammonia, temperature 70°C to 90°C, pressure 1.5 to 3.5 MPa. The high-temperature and high-pressure ammonia gas enters the condenser. After being cooled by the cooling medium (water and air), the ammonia gas begins to cool and condense, turning into high-pressure liquid ammonia, and then returns to the high-pressure liquid storage tank for recycling. Liquid ammonia, temperature -10°C to 20°C, pressure 1.5 to 3.5 MPa.

[0093] The second step is the refrigerant loop process: The refrigerant (alcohol water) is stored in the refrigerant storage tank. According to different temperatures, the refrigerant will show different distributions in the storage tank. The refrigerant temperature at the upper part of the tank is relatively high (generally -2.8°C), and the temperature at the lower part is relatively low (-4°C). Therefore, the liquid outlet is located at the upper part of the tank body, and the liquid return port is located at the lower part of the tank body. The high-temperature refrigerant is pumped from the upper part of the refrigerant storage tank into the evaporator (plate heat exchanger). After heat exchange (the liquid ammonia absorbs the heat of the refrigerant), the refrigerant is converted into low-temperature refrigerant and returns to the lower part of the refrigerant storage tank. It ends until the refrigerant temperature in the tank body meets the set temperature requirements.

[0094] In this embodiment, the control of the ammonia refrigerant system operation process includes When the temperature of the refrigerant storage tank is higher than the set temperature, the ammonia refrigerant system is automatically started to circulate for refrigeration. After the ammonia refrigerant system is started, it first conducts self-checks on each unit, including operating status detection, fault status detection, manual / automatic status monitoring, and local / remote control status detection.

[0095] When the above self-check values are not all 0, the system self-check value RUN = 0, the start is stopped, and the reason for not allowing the start is prompted; when the self-check values are all 0, the system self-check value RUN = 1, the self-check passes, the system starts, and enters the next step of system operation.

[0096] As Figure 4As shown, the process of controlling the operation of the ammonia refrigerant system includes S1. In the stage of refrigerant entering the refrigerant storage tank, the liquid level of the refrigerant storage tank is controlled. If the liquid level detected by the second liquid level sensor does not reach the preset liquid level threshold, refrigerant is replenished into the refrigerant storage tank until the preset liquid level threshold is reached, and this stage ends and enters the refrigerant pre-cycle stage.

[0097] S2. Start the refrigerant storage tank unit, start the refrigerant circulation pump and the pipeline automatic control valve, automatically adjust and control the rotation speed of the refrigerant circulation pump according to the preset flow rate, and display the refrigerant flow rate in real time.

[0098] S3. Start the condenser unit, start the corresponding condenser according to the priority (the one with the minimum cumulative operation time is started first), start the condenser water pump (the first condenser water pump or the second condenser water pump or the third condenser water pump), and start the condenser fan (the first condenser fan, the second condenser fan, the third condenser fan); among them, the condensate water pump (the first condensate water pump or the second condensate water pump or the third condensate water pump) is interlocked with the condenser liquid level switch (the first condenser liquid level switch or the second condenser liquid level switch or the third condenser liquid level switch). If the detection value of the condenser liquid level switch is 1, start the condenser water pump, and if the detection value is 0, stop the water pump.

[0099] S4. Start the high-pressure liquid storage barrel unit, detect and display the temperature and pressure of the first ammonia liquid in the liquid storage barrel unit.

[0100] S5. Start the gas-liquid separator unit, detect the liquid level, and control the input and output of ammonia liquid and refrigerant.

[0101] S6. When the above units are started and operate normally, when the refrigerant circulation flow rate value reaches the preset value and maintains the operation set time value, it transfers to the next stage of preparing refrigerant.

[0102] S7. Compare the sampled value of the refrigerant outlet temperature of the evaporator with the preset value, and adjust and control the rotation speed of the refrigerant circulation pump.

[0103] S8. Compare the pressure value at the outlet of the compressor with the preset pressure value. If the pressure value at the outlet of the compressor is continuously greater than the upper limit of the preset pressure value for 10 minutes, then if the condenser is not started, start the condenser, and if the condenser has already been started, increase the number of started condensers, and finally keep the pressure value at the outlet of the compressor within the range allowed by the preset pressure threshold.

[0104] S9. The condensate water pump (the first condensate water pump or the second condensate water pump or the third condensate water pump) is interlocked with the condenser liquid level switch (the first condenser liquid level switch or the second condenser liquid level switch or the third condenser liquid level switch). If the liquid level detection value is 1, start the condensate water pump, and if the detection value is 0, stop the condenser water pump.

[0105] S10. Detect the first liquid level switch and the second liquid level switch of the gas-liquid separator unit, and interlock to control the start and stop of the first ammonia liquid inlet automatic control valve and the second ammonia liquid inlet automatic control valve. When the first liquid level switch is triggered, the first ammonia liquid inlet automatic control valve and the second ammonia liquid inlet automatic control valve are opened to supplement ammonia liquid into the gas-liquid separator unit; when the second liquid level switch is triggered, the first ammonia liquid inlet automatic control valve and the second ammonia liquid inlet automatic control valve are closed to prevent liquid ammonia from entering the compressor and damaging the compressor.

[0106] In this embodiment, the control process of the ammonia refrigeration medium system further includes S11. Detect and display the temperature value and pressure value of the first ammonia liquid in the high-pressure liquid storage tank unit. When the sampled value is greater than the first preset temperature value and the second pressure preset value, an alarm is given and the system operation is stopped.

[0107] S12. Control the ammonia refrigeration medium system to stop operating according to the preset temperature value threshold. When the temperature of the refrigerant in the refrigerant storage tank is greater than the preset threshold, the ammonia refrigeration medium system is stopped.

[0108] After the ammonia refrigeration medium system receives more than 2 shutdown commands, it stops the unit operation in sequence. The sequence includes stopping the compressor unit - stopping the condenser fan - stopping the condenser circulating water pump - stopping the condenser unit - closing the automatic control valve - stopping the gas-liquid separator unit - stopping the evaporator unit - stopping the high-pressure liquid storage tank unit - stopping the refrigerant circulating pump - stopping the refrigerant storage tank unit - stopping the entire ammonia refrigeration medium system.

[0109] In one embodiment, the ammonia refrigeration medium remote integrated automatic control system further includes During the operation of the system, the error between the output variables of the system (such as the temperature of the refrigerant output by the evaporator, the pressure output by the compressor, etc.) and the preset values is monitored in real time. According to the magnitude and direction of the error, the control rules are adjusted in real time. For example, when the temperature of the refrigerant output by the evaporator is higher than the preset value, the rotation speed of the refrigerant circulating pump is increased to improve the refrigeration effect.

[0110] In addition to error feedback, the control rules can also be adjusted according to the performance indicators of the system (such as energy consumption, refrigeration efficiency, etc.). When the energy consumption of the ammonia refrigeration medium system is too high, the control rules are adjusted to reduce unnecessary equipment operation and lower the energy consumption. Through continuous feedback and adjustment, the system is always maintained in the best operating state.

[0111] As the operating environment and working conditions of the ammonia refrigeration medium system change, some parameters in the control rules may need to be adaptively adjusted. An adaptive fuzzy control algorithm can be used to automatically adjust these parameters according to the real-time operating data of the system, so that the rules can better adapt to the changing environment.

[0112] During the operation of the system, if it is found that some rules are no longer applicable or new working conditions occur, the control rules need to be adaptively adjusted. Through the online learning and rule update mechanism, new knowledge and experience can be continuously learned, and the rules in the rule base can be updated to make the system more adaptable and robust.

[0113] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the present disclosure in each embodiment.

Claims

1. An ammonia refrigerant remote integrated automatic control system for controlling an ammonia refrigerant system, characterized in that: include: Data acquisition subsystem and intelligent control subsystem; among them, The data acquisition subsystem is used to collect the operating status data of the ammonia refrigerant system; The intelligent control subsystem is used to set threshold data for the operation of the ammonia refrigerant system, and is also used to process the state data and threshold data according to a preset first control rule or a second control rule to control the operation of the ammonia refrigerant system.

2. The ammonia refrigerant remote integrated automatic control system according to claim 1, characterized in that: The intelligent control subsystem includes an operation station, a main station and at least one substation; The operation station is used to display the operating status data of the ammonia refrigerant system, and is also used to set the threshold data, the first control rule and the second control rule of the operating of the ammonia refrigerant system. The master station is used to generate a data acquisition control instruction and send the data acquisition control instruction to each substation, and is also used to process the state data and threshold data according to the first control rule or the second control rule, generate a control rule instruction, and send the control rule instruction to each substation; The substation is used to transmit the operating status data of the ammonia refrigerant system to the main station according to the data acquisition control instruction, and is also used to control the operation of the ammonia refrigerant system according to the control rule instruction.

3. The ammonia refrigerant remote integrated automatic control system according to claim 2, characterized in that: The ammonia refrigerant system includes an ammonia circulation subsystem and a refrigerant circulation subsystem; wherein, The ammonia circulation subsystem includes a compressor unit, a condenser unit, a thermosyphon tank, a high-pressure liquid storage barrel unit, a gas-liquid separator unit and an evaporator unit; Wherein, the compressor unit is used to prepare the input ammonia gas into the first ammonia gas, and transport the first ammonia gas to the condenser unit; The condenser unit includes a plurality of condensers for cooling the first ammonia gas and converting it into a first ammonia liquid; and delivering the first ammonia liquid to the thermosyphon tank; The thermosyphon tank is used to adjust the flow rate of the first ammonia liquid output by the condenser unit and transport the first ammonia liquid to the high-pressure liquid storage barrel unit; The high-pressure liquid storage barrel unit is used to store the first ammonia liquid and transmit the first ammonia liquid to the gas-liquid separator unit; The gas-liquid separator unit is used to separate the first ammonia liquid input from the high-pressure liquid storage tank from the second ammonia gas output from the evaporator unit, and to transport the first ammonia liquid to the evaporator unit and the second ammonia gas to the compressor unit; The evaporator unit is used to make the first ammonia liquid absorb the heat of the first refrigerant in the refrigerant circulation subsystem to obtain a second refrigerant, and transmit the second refrigerant to the refrigerant circulation subsystem; The refrigerant circulation subsystem includes a refrigerant storage tank unit and a refrigerant circulation pump; The refrigerant storage tank unit is used to store refrigerant; The refrigerant circulation pump is used to transfer the first refrigerant in the refrigerant storage tank unit to the evaporator unit.

4. The ammonia refrigerant remote integrated automatic control system according to claim 3, characterized in that: The data acquisition subsystem comprises: A first temperature sensor is disposed at the outlet of the compressor unit and is used to detect the temperature value of the first ammonia gas output by the compressor; A second temperature sensor is disposed at the inlet of the compressor unit and is used to detect the temperature value of the ammonia gas sucked into the compressor; a third temperature sensor, disposed at an inlet position of the evaporator unit, for detecting a temperature value of the first refrigerant input to the evaporator unit; a fourth temperature sensor, disposed at an outlet of the evaporator unit, for detecting a temperature value of the second refrigerant output by the evaporator unit; A distributed temperature detection module is arranged in the refrigerant storage tank unit and is used to detect the temperature value of the refrigerant in the refrigerant storage tank unit; wherein the distributed temperature detection module includes a fifth temperature sensor, a sixth temperature sensor, a seventh temperature sensor and an eighth temperature sensor; a ninth temperature sensor, disposed in the high-pressure liquid storage barrel, for detecting a temperature value of the first ammonia liquid in the high-pressure liquid storage barrel; A first pressure sensor is arranged at the inlet position of the compressor unit and is used to detect the pressure value at the inlet of the compressor unit; A second pressure sensor is disposed at the outlet of the compressor unit and is used to detect the pressure value at the outlet of the compressor unit; a third pressure sensor, disposed in the high-pressure liquid storage barrel unit, for detecting a pressure value of the first ammonia liquid in the high-pressure liquid storage barrel unit; A first liquid level sensor, used to detect the liquid level value in the high-pressure liquid storage barrel unit; A second liquid level sensor, used to detect the liquid level value in the refrigerant storage tank unit; Flow sensor, used to detect the flow rate of refrigerant output by the variable frequency refrigerant circulation pump; The ambient temperature sensor is used to detect the ambient temperature value of the ammonia refrigerant system.

5. The ammonia refrigerant remote integrated automatic control system according to claim 4, characterized in that: The operating station comprises: A condenser priority control module, used to accumulate the operating time of each condenser in the condenser unit, generate a priority queue, and start the condenser with the shortest operating time first; A hysteresis pressure control module, configured to start the condensers one by one when the pressure value at the compressor unit output port is greater than a first preset pressure value threshold range for a period exceeding a preset time until the pressure value at the compressor unit output port returns to the first preset pressure value threshold range; A refrigerant stratified temperature control module, used to control the operation of the ammonia refrigerant system to eliminate the temperature difference of the refrigerant in the refrigerant storage tank unit when the weighted average temperature value detected by the distributed temperature detection module is greater than a preset temperature value threshold; A dual-threshold alarm module, configured to trigger an audible and visual alarm and issue an emergency stop command when it is detected that the temperature of the first ammonia liquid in the high-pressure liquid storage barrel unit is greater than a second preset temperature value and / or the pressure of the first ammonia liquid is greater than a second preset pressure value; The compressor low temperature protection module is used to stop the intake of ammonia when it is detected that the inlet temperature of the compressor unit is lower than a third preset temperature value.

6. The ammonia refrigerant remote integrated automatic control system according to claim 5, characterized in that: The first control rule includes: According to the pressure value of the compressor unit output port, adjusting the start-up quantity of the condenser in the condenser unit; adjusting the speed of the refrigerant circulation pump according to a comparison result between the temperature value of the second refrigerant output by the evaporator unit and a fourth preset temperature value; Controlling whether ammonia liquid enters the gas-liquid separator according to a comparison result between a liquid level detection value in the gas-liquid separator unit and a preset liquid level threshold; The operation of the ammonia refrigerant system is controlled according to the comparison result between the weighted average temperature value detected by the distributed temperature detection module and the preset temperature value threshold.

7. The ammonia refrigerant remote integrated automatic control system according to claim 6, characterized in that: The second control rule includes: Calculating a weighted sum according to the state data and a preset weighted sum calculation formula; When the weighted sum is in a first preset interval, generating a control instruction for adjusting the number of condenser operations; When the weighted sum is in the second preset interval, a control instruction for adjusting the rotation speed of the refrigerant circulation pump is generated.

8. The ammonia refrigerant remote integrated automatic control system according to claim 7, characterized in that: The weighted sum formula is: S=a×Y+b×J+c×K+d×L Among them, S is the weighted sum; a is the weight coefficient of the temperature value of the second refrigerant output by the evaporator unit, b is the weight coefficient of the outlet pressure value of the compressor unit, c is the weight coefficient of the liquid level value in the refrigerant tank unit, and d is the weight coefficient of the ambient temperature value; Y is the temperature value of the second refrigerant output by the evaporator unit, J is the outlet pressure value of the compressor unit, K is the liquid level value in the refrigerant tank unit, and L is the ambient temperature value.

9. A control method applied to the ammonia refrigerant remote integrated automatic control system according to any one of claims 1 to 8, characterized in that: include: Preprocessing the first data and the second data; Process the preprocessed first data and second data according to a preset first control rule or a second control rule to generate the control rule instruction; The first data is status data of the ammonia refrigerant system during operation; The second data is threshold data preset before the ammonia refrigerant system is operated; The ammonia refrigerant system is controlled according to the control rule instructions.

10. The control method of the ammonia refrigerant remote integrated automatic control system according to claim 9, characterized in that: The preprocessing includes performing noise filtering and normalization processing on the first data.

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