A control system for intelligent pressure regulation of a district central cooling pipe network

Abstract

The application relates to a control system for intelligent pressure regulation of a district central cooling pipe network, and belongs to the technical field of central cooling, which comprises a cold station, a cold station control system, a plurality of plate exchanger rooms and a plurality of plate exchanger room control systems; the cold station control system comprises a first control module, and the plate exchanger room control system comprises a second control module connected with the first control module; the cold station comprises a variable frequency water pump connected with the first control module and a cold station water supply and return water pressure difference sensor, the variable frequency water pump is connected with the cooling pipe network; the plate exchanger room is connected with the cooling pipe network and a user end, a cooling side switch valve, a cooling side adjusting valve, a cooling side water supply temperature sensor and a cooling side return water temperature sensor connected with the second control module are arranged on a water supply pipe of the cooling pipe network side, a cooling side water supply temperature sensor connected with the second control module is arranged on a water supply pipe of the user end side, and the plate exchanger room is provided with a plate exchanger temperature sensor connected with the second control module, and the application has the effect of reducing the power consumption of the cooling variable frequency pump.

Description

Technical Field

[0001] This application relates to the field of centralized cooling, and in particular to a control system for intelligent pressure regulation of a regional centralized cooling network. Background Technology

[0002] In district cooling systems, pipeline pressure regulation and control is a key link in ensuring the stable and efficient operation of the system. At present, the main control system commonly used in the industry is the constant pressure regulation mode. Constant pressure regulation is the mainstream control method, which sets a fixed pressure difference between the supply and return water pipelines and keeps it constant, which can ensure the stability of cooling supply to a certain extent.

[0003] However, with the expansion of system scale and the increasing demands for energy conservation, the problems of existing constant pressure regulation and control systems have become more prominent:

[0004] Firstly, when multiple heat exchanger rooms experience abnormal alarms, the pipeline network still maintains constant pressure, and the cooling station's variable frequency pumps operate at high frequency, resulting in unnecessary energy consumption.

[0005] Secondly, regardless of whether the heat exchanger room is in use, the pipeline network maintains constant pressure, and the cooling variable frequency pump runs continuously at high frequency, resulting in serious energy waste and failure to save energy.

[0006] Third, when the flow rate in the heat exchanger decreases and the opening of the regulating valve decreases, the pipeline network still maintains a relatively high pressure differential setpoint. In order to maintain the high-frequency operation of the cooling variable frequency pump, the power consumption increases.

[0007] Therefore, how to effectively adjust the differential pressure of the pipeline network and achieve intelligent regulation to reduce the power consumption of the variable frequency pump for cooling has become a key issue for the energy-saving operation of regional centralized cooling systems. Utility Model Content

[0008] To reduce the power consumption of variable frequency pumps for cooling, this application provides a control system for intelligent pressure regulation of regional centralized cooling pipe networks.

[0009] This application provides a smart pressure regulation control system for a regional centralized cooling network, which adopts the following technical solution:

[0010] A control system for intelligent pressure regulation of a regional centralized cooling network includes a cooling station, a cooling station control system, multiple plate heat exchangers, and multiple plate heat exchanger control systems.

[0011] The cooling plant control system includes a first control module, and the inter-panel control system includes a second control module, with the first control module and the second control module connected together.

[0012] The cooling station includes multiple variable frequency water pumps and a cooling station supply and return water differential pressure sensor. The variable frequency water pumps are connected to the cooling network through water supply pipes. The cooling station supply and return water differential pressure sensor is installed at the water supply point and the water return point. Both the variable frequency water pumps and the cooling station supply and return water differential pressure sensor are connected to the first control module.

[0013] One end of the heat exchanger room is connected to the cooling network via a water supply pipe, and the other end of the heat exchanger room is connected to the user end via a water supply pipe. A cooling-side switch valve and a cooling-side supply water temperature sensor are installed on the water supply pipe on the cooling network side, and a cooling-side regulating valve and a cooling-side return water temperature sensor are installed on the return water pipe. A user-side supply water temperature sensor is installed on the water supply pipe on the user end side, and a heat exchanger temperature sensor is installed in the heat exchanger room. The cooling-side switch valve, cooling-side regulating valve, heat exchanger temperature sensor, cooling-side supply water temperature sensor, cooling-side return water temperature sensor, and cooling-side supply water temperature sensor are all connected to the second control module.

[0014] By adopting the above technical solution, the heat exchanger temperature sensor, the cooling-side supply water temperature sensor, the cooling-side return water temperature sensor, the user-side supply water temperature sensor, and the cooling-side regulating valve transmit the detected heat exchanger temperature data, cooling-side supply water temperature data, cooling-side return water temperature data, user-side supply water temperature data, and cooling-side regulating valve opening data to the second control module in real time through the analog input / output module. The user-side supply water temperature sensor transmits the user-side supply water temperature data to the second control module. When the second control module receives the heat exchanger temperature data, the cooling-side supply water temperature data, and the cooling-side regulating valve opening data, it sends the detected data to the second control module in real time. When processing data such as return water temperature, the opening / closing status of the cooling-side on / off valve, the opening degree of the cooling-side regulating valve, and the cooling-side supply water temperature, the heat exchanger temperature, cooling-side supply water temperature, cooling-side return water temperature, and cooling-side supply water temperature are compared with the corresponding thresholds. The comparison results, the opening / closing status of the cooling-side on / off valve, and the opening degree of the cooling-side regulating valve are sent to the first control module. The first control module adjusts the number and frequency of the variable frequency water pumps based on the comparison results, the opening / closing status of the cooling-side on / off valve, and the opening degree of the cooling-side regulating valve, thereby improving the operating efficiency of the variable frequency water pumps and achieving energy saving.

[0015] Optionally, the chiller plant control system further includes an analog input module and an analog output module;

[0016] Both the analog input module and the analog output module are connected to the first control module. The analog input module is also connected to the cooling station supply and return water differential pressure sensor, and the analog output module is also connected to the variable frequency water pump.

[0017] By adopting the above technical solution, the analog input module is connected to the differential pressure sensor of the chiller supply and return water, which can accurately collect the analog signal of the differential pressure between the supply and return water. The analog output module is connected to the variable frequency water pump. The first control module outputs the corresponding analog control signal to the variable frequency water pump according to the differential pressure data collected by the analog input module, thereby accurately controlling the operating frequency of the variable frequency water pump and realizing continuous adjustment of the water pump speed.

[0018] Optionally, the heat exchanger control system further includes an analog input / output module and a digital input / output module. Both the analog input / output module and the digital input / output module are connected to the second control module. The analog input / output module is also connected to the cooling-side regulating valve, the heat exchanger temperature sensor, the cooling-side supply water temperature sensor, the cooling-side return water temperature sensor, and the cooling-side supply water temperature sensor. The digital input / output module is also connected to the cooling-side switching valve.

[0019] By adopting the above technical solution, the analog input / output module is connected to the heat exchanger temperature sensor, the cooling side supply water temperature sensor, the cooling side return water temperature sensor, the cooling side regulating valve, and the cooling side return water temperature sensor, thereby accurately acquiring the analog signals output by these sensors and the opening degree of the cooling side regulating valve. The digital input / output module is connected to the cooling side switching valve, thereby accurately acquiring the switching state of the cooling side switching valve.

[0020] Optionally, multiple variable frequency water pumps may be connected in parallel.

[0021] By adopting the above technical solution, the number and frequency of multiple variable frequency water pumps can be flexibly adjusted according to actual needs to achieve the best matching of flow rate and head, thereby realizing on-demand adjustment, avoiding the operation of water pumps under inefficient conditions, and improving the operating efficiency of variable frequency water pumps.

[0022] Optionally, the chiller plant control system also includes a first dual-channel analog isolation barrier, which is disposed between the chiller plant supply and return water differential pressure sensor and the analog input module, and between the analog output module and the variable frequency water pump.

[0023] By adopting the above technical solution, the first dual-channel analog isolation barrier can eliminate interference, enabling the analog input module to receive more accurate differential pressure signals, and the analog output module to output control signals to the variable frequency water pump more accurately, thereby improving the accuracy of the entire control system. This allows the variable frequency water pump to adjust its operating frequency more precisely according to the actual differential pressure requirements, thus achieving more precise differential pressure control of the cooling network.

[0024] Optionally, the heat exchanger control system further includes a second dual-channel analog isolation barrier, which is disposed between the analog input / output module and the cooling-side regulating valve, the heat exchanger temperature sensor, the cooling-side supply water temperature sensor, the cooling-side return water temperature sensor, and the cooling-side supply water temperature sensor.

[0025] Optionally, the switch room control system may also include a switch that provides an industrial network for connecting the various modules and sensors.

[0026] Optionally, the chiller plant control system may also include a switch that provides an industrial network for connecting the various modules and sensors.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] The heat exchanger temperature sensor, cooling-side supply water temperature sensor, cooling-side return water temperature sensor, and cooling-side supply water temperature sensor transmit the detected heat exchanger temperature data, cooling-side supply water temperature data, cooling-side return water temperature data, and cooling-side supply water temperature data in real time to the second control module via an analog input / output module. The cooling-side regulating valve sends its opening degree to the second control module, and the cooling-side switching valve sends its opening and closing status to the second control module. When the second control module receives the heat exchanger temperature data, cooling-side supply water temperature data, cooling-side return water temperature data, cooling-side supply water temperature data, cooling-side regulating valve opening degree, and cooling-side switching valve opening and closing status, it will... The plate heat exchanger temperature data, cooling side supply water temperature data, cooling side return water temperature data, and cooling side supply water temperature data are compared with the corresponding thresholds. The comparison results, the opening degree of the cooling side regulating valve, and the opening and closing status of the cooling side switching valve are sent to the first control module. The first control module adjusts the number and frequency of the variable frequency water pumps according to the comparison results, the opening degree of the cooling side regulating valve, and the opening and closing status of the cooling side switching valve, thereby improving the operating efficiency of the variable frequency water pumps to achieve energy saving. That is, under the premise of increasing cooling capacity at the cooling station outlet, the power consumption decreases. Under the premise of consistent supply water temperature, the supply water pressure decreases, the supply and return water temperature difference increases, the frequency of the cooling variable frequency pump decreases, and the power consumption of the cooling variable frequency pump decreases, thus achieving energy saving. Attached Figure Description

[0029] Figure 1 This is a structural block diagram illustrating the distribution of various modules and sensors in the heat exchanger room in the embodiments of this application.

[0030] Figure 2 This is a structural block diagram illustrating the distribution of the variable frequency water pump and the differential pressure sensor for the supply and return water of the chiller plant in the embodiments of this application.

[0031] Figure 3 This is the structure embodying the control of the first control module and the second control module in the embodiments of this application.

[0032] Explanation of reference numerals in the attached diagram: 1. Cooling plant; 11. Variable frequency water pump; 12. Cooling plant supply and return water differential pressure sensor; 2. Cooling plant control system; 21. First control module; 22. Analog input module; 23. Analog output module; 24. First dual-channel analog isolation barrier; 3. Heat exchanger room; 31. Cooling side switch valve; 32. Cooling side supply water temperature sensor; 33. Cooling side regulating valve; 34. Cooling side supply water temperature sensor; 35. Heat exchanger temperature sensor; 36. Cooling side return water temperature sensor; 4. Heat exchanger room control system; 41. Second control module; 42. Analog input / output module; 43. Digital input / output module; 44. Second dual-channel analog isolation barrier; 5. Cooling pipe network. Detailed Implementation

[0033] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0034] This application discloses an intelligent pressure regulation control system for a regional centralized cooling network, referring to... Figure 1 , Figure 2 and Figure 3 The intelligent pressure regulation control system for the regional centralized cooling network includes a cooling station 1, a cooling station control system 2, multiple plate heat exchangers 3, and multiple plate heat exchanger control systems 4.

[0035] The chiller station 1 includes multiple variable frequency water pumps 11 and a chiller station supply and return water differential pressure sensor 12. The variable frequency water pumps 11 are connected to the chiller supply network 5 through the water supply pipe, and the multiple variable frequency water pumps 11 are set in parallel. The chiller station supply and return water differential pressure sensor 12 is set at the water supply point and the water return point of the chiller station 1.

[0036] The chiller plant control system 2 includes a first control module 21, an analog input module 22, an analog output module 23, a first dual-channel analog isolation barrier 24, and a switch (not shown in the figure) for providing an industrial network. The analog input module 22 and the analog output module 23 are connected to the first control module 21 through the industrial network. The analog output module 23 and the analog input module 22 are both connected to the corresponding first dual-channel analog isolation barrier 24 through the industrial network. The chiller plant supply and return water differential pressure sensor 12 is connected to the first dual-channel analog isolation barrier 24 on the analog input module 22 side through the industrial network. The variable frequency water pump 11 is connected to the first dual-channel analog isolation barrier 24 on the analog output module 23 side through the industrial network.

[0037] One end of the heat exchanger room 3 is connected to the cooling network 5 via a water supply pipe, and the other end of the heat exchanger room 3 is connected to the user end via a water supply pipe. A cooling-side switch valve 31 and a cooling-side water supply temperature sensor 34 are installed on the water supply pipe on the cooling network 5 side. A cooling-side regulating valve 33 and a cooling-side return water temperature sensor 36 are installed on the return water pipe on the cooling side. A cooling-side water supply temperature sensor 32 is installed on the water supply pipe on the user end side, and a heat exchanger temperature sensor 35 is installed in the heat exchanger room 3.

[0038] The heat exchanger control system 4 includes a second control module 41, an analog input / output module 42, a digital input / output module 43, a second dual-channel analog isolation barrier 44, and a switch for providing an industrial network. The analog input / output module 42 and the digital input / output module 43 are both connected to the second control module 41 through the industrial network. The analog input / output module 42 and the digital input / output module are also connected to their respective second dual-channel analog isolation barriers 44 through the industrial network. The cold-side supply water temperature sensor 32, the cold-side regulating valve 33, the cold-side supply water temperature sensor 34, the heat exchanger temperature sensor 35, and the cold-side return water temperature sensor 36 are connected to the second dual-channel analog isolation barrier 44 on the analog input / output module 42 side through the industrial network. The cold-side switching valve 31 is connected to the second dual-channel analog isolation barrier 44 on the digital input / output module 43 side through the industrial network. The first control module 21 and the second control module 41 are connected through the industrial network.

[0039] The heat exchanger temperature sensor 35 detects the heat exchanger temperature data in real time. The cooling side supply water temperature sensor 34 detects the cooling side supply water temperature data in real time. The cooling side return water temperature sensor 36 detects the cooling side return water temperature data in real time. The user-side supply water temperature sensor 32 detects the user-side supply water temperature data in real time. The heat exchanger temperature sensor 35, the cooling side supply water temperature sensor 34, the cooling side return water temperature sensor 36, and the user-side supply water temperature sensor 32 transmit the detected heat exchanger temperature data, cooling side supply water temperature data, cooling side return water temperature data, and user-side supply water temperature data in real time to the second control module 41 through the analog input / output module 42. When the second control module 41 receives the heat exchanger temperature data, the cooling side supply water temperature data, and the cooling side return water temperature data... When processing heat exchanger temperature data and cooling water supply temperature data, the heat exchanger temperature data, cooling water supply temperature data, cooling water return temperature data, and cooling water supply temperature data are compared with the corresponding thresholds. The number N1 of heat exchanger rooms that exceed the thresholds is recorded. For example, if any one or more of the heat exchanger temperature data, cooling water supply temperature data, cooling water return temperature data, and cooling water supply temperature data exceed the threshold in one heat exchanger room, the number N1 is 1; if at least one of the heat exchanger temperature data, cooling water supply temperature data, cooling water return temperature data, and cooling water supply temperature data exceeds the threshold in two heat exchanger rooms, the number N1 is 2, and so on.

[0040] The cooling-side switching valve 31 sends its opening and closing status to the second control module 41 in real time via the digital input / output module 43. The cooling-side regulating valve 33 sends its opening degree to the second control module 41 in real time via the analog input / output module 42. The second control module 41 records the number N2 of cooling-side switching valves 31 that are open and the opening degree N3 of cooling-side regulating valves 33. For example, if one cooling-side switching valve 31 is open, the number N2 of cooling-side switching valves 31 is 1; if two cooling-side switching valves 31 are open, the number N2 of cooling-side switching valves 31 is 2, and so on. The number N3 of cooling-side regulating valves 33 with an opening degree less than D% is also recorded.

[0041] Among them, the plate heat exchanger temperature data, the threshold corresponding to the cold side, and the opening degree D% of the cold side regulating valve are all preset in the second control module 41.

[0042] The second control module 41 sends quantities N1, N2, and N3 to the first control module 21 via the industrial network. The cooling station supply and return water pressure differential sensor 12 sends the cooling station supply water pressure data and cooling station return water pressure data to the first control module 21 in real time. The first control module 21 calculates the pressure differential based on the cooling station supply water pressure data and cooling station return water pressure data. The first control module 21 adjusts the pressure differential setpoint of the cooling pipe network based on N1, N2, and N3. The second control module 41 adjusts the number and frequency of variable frequency water pumps 11 through a stored adjustment algorithm, thereby improving the operating efficiency of the variable frequency water pumps 11 to achieve energy saving. The adjustment algorithm adopts an existing algorithm.

[0043] The implementation principle of the intelligent pressure regulation control system for a regional centralized cooling network according to an embodiment of this application is as follows:

[0044] The heat exchanger temperature sensor 35, the cooling-side supply water temperature sensor 34, the cooling-side return water temperature sensor 36, and the user-side supply water temperature sensor 32 transmit the detected heat exchanger temperature data, user-side supply water temperature data, cooling-side return water temperature data, and cooling-side supply water temperature data to the second control module 41 in real time via the industrial network. When the second control module 41 receives the heat exchanger temperature data, cooling-side supply water temperature data, cooling-side return water temperature data, and user-side supply water temperature data, it compares these data with the corresponding thresholds and records any exceedances. The second control module 41 records the number N1 of plate heat exchanger temperature data, cooling side supply water temperature data, cooling side return water temperature data, and cooling side supply water temperature data. The second control module 41 records the number N2 of cooling side switch valves 31 in the open state and the opening degree N3 of cooling side regulating valves. The second control module 41 sends the numbers N1, N2, and N3 to the first control module 21 through the industrial network. The first control module 21 adjusts the differential pressure setting value of the cooling pipe network according to N1, N2, and N3. The second control module 41 adjusts the number and frequency of variable frequency water pumps 11 through the stored adjustment algorithm, thereby improving the operating efficiency of variable frequency water pumps 11 to achieve energy saving.

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A control system for intelligent pressure regulation of a district cooling pipe network, characterized in that: This includes a chiller plant, a chiller plant control system, multiple plate heat exchanger rooms, and multiple plate heat exchanger room control systems; The cooling plant control system includes a first control module, and the plate heat exchanger room control system includes a second control module. The first control module and the second control module are connected. The cooling station includes multiple variable frequency water pumps and a cooling station supply and return water differential pressure sensor. The variable frequency water pumps are connected to the cooling network through water supply pipes. The cooling station supply and return water differential pressure sensor is installed at the water supply point and the water return point. Both the variable frequency water pumps and the cooling station supply and return water differential pressure sensor are connected to the first control module. One end of the heat exchanger room is connected to the cooling network via a water supply pipe, and the other end of the heat exchanger room is connected to the user end via a water supply pipe. A cooling-side switch valve and a cooling-side supply water temperature sensor are installed on the water supply pipe on the cooling network side, and a cooling-side regulating valve and a cooling-side return water temperature sensor are installed on the return water pipe. A user-side supply water temperature sensor is installed on the water supply pipe on the user end side, and a heat exchanger temperature sensor is installed in the heat exchanger room. The cooling-side switch valve, cooling-side regulating valve, heat exchanger temperature sensor, cooling-side supply water temperature sensor, cooling-side return water temperature sensor, and cooling-side supply water temperature sensor are all connected to the second control module.

2. The control system for intelligent pressure regulation of a district chilled water pipe network according to claim 1, wherein: The cooling plant control system also includes an analog input module and an analog output module; Both the analog input module and the analog output module are connected to the first control module. The analog input module is also connected to the cooling station supply and return water differential pressure sensor, and the analog output module is also connected to the variable frequency water pump.

3. The control system for intelligent pressure regulation of a district chilled water pipe network according to claim 1, wherein: The heat exchanger control system further includes an analog input / output module and a digital input / output module. Both the analog input / output module and the digital input / output module are connected to the second control module. The analog input / output module is also connected to the cooling side regulating valve, the heat exchanger temperature sensor, the cooling side supply water temperature sensor, the cooling side return water temperature sensor, and the cooling side supply water temperature sensor. The digital input / output module is also connected to the cooling side switching valve.

4. The control system for intelligent pressure regulation of a district chilled water pipe network according to claim 1, wherein: Multiple variable frequency water pumps are connected in parallel.

5. The control system for intelligent pressure regulation of district chilled water pipe network according to claim 2, characterized in that: The chiller plant control system also includes a first dual-channel analog isolation barrier, which is disposed between the chiller plant supply and return water differential pressure sensor and the analog input module, and between the analog output module and the variable frequency water pump.

6. The intelligent pressure regulation control system for a regional centralized cooling network according to claim 3, characterized in that: The plate heat exchanger control system also includes a second dual-channel analog isolation barrier, which is installed between the analog input / output module and the cooling-side regulating valve, the plate heat exchanger temperature sensor, the cooling-side supply water temperature sensor, the cooling-side return water temperature sensor, and the cooling-side supply water temperature sensor.

7. The control system for intelligent pressure regulation of district chilled water pipe network according to claim 3, characterized in that: The switch room control system also includes switches that provide an industrial network for connecting various modules and sensors.

8. The intelligent pressure regulation control system for a regional centralized cooling network according to claim 2, characterized in that: The cooling plant control system also includes a switch that provides an industrial network for connecting various modules and sensors.

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