Control Method, Device, Equipment and Medium for Central Air Conditioning Chilled Water System

Abstract

The present invention is mainly used in the technical fields of refrigerators and central air conditioners. The present invention discloses a control method, device, equipment and medium for a central air conditioner chilled water system. The method includes: obtaining a set pressure difference value of the central air conditioner chilled water system; adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value; controlling a chilled water pump of the central air conditioner chilled water system based on the adjusted set pressure difference value to adjust the chilled water flow rate of the central air conditioner chilled water system. This application can reduce the energy consumption of the central air conditioner chilled water system.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerators and central air conditioners, and specifically relates to a control method, device, equipment and medium for a central air conditioner chilled water system. Background Art

[0002] With the improvement of China's economic strength, high-end buildings and public buildings using central air conditioning systems have become an important symbol of urban modernization. Statistics show that the energy consumption of central air conditioning systems accounts for more than 60% of the total building energy consumption, and its energy consumption plays a decisive role in the total building energy consumption. This means that while pursuing a comfortable environment, a huge energy cost has also been paid. Therefore, reducing the energy consumption of central air conditioning systems is not only an extremely important task in the field of building energy conservation, but also a research direction that scientific and technological workers continue to explore and focus on. Summary of the Invention

[0003] One aspect of the present invention provides a control method, device, equipment and medium for a central air conditioner chilled water system, which can reduce the energy consumption of the central air conditioner chilled water system.

[0004] The present invention provides a control method for a central air conditioner chilled water system, and the method includes:

[0005] Obtain the set pressure difference value of the central air conditioner chilled water system;

[0006] Within a preset period, adjust the set pressure difference value to obtain an adjusted set pressure difference value;

[0007] Based on the adjusted set pressure difference value, control the chilled water pump of the central air conditioner chilled water system to adjust the chilled water flow of the central air conditioner chilled water system.

[0008] Optionally, the control method for the central air conditioner chilled water system includes:

[0009] When it is detected that the communication is in an abnormal state, stop adjusting the set pressure difference value, and delete the adjusted set pressure difference value, so that the set pressure difference value of the central air conditioner chilled water system changes to a preset set pressure difference value.

[0010] Optionally, the control method for the central air conditioner chilled water system includes:

[0011] When adjusting the set pressure difference value, determine the target set pressure difference value and use it as the adjusted set pressure difference value according to the optimal working area of the chilled water pump in the preset pressure difference change characteristic analysis diagram and the preset fuzzy PID algorithm, wherein the pressure difference change characteristic analysis diagram is generated based on the water pump characteristic curve, the pipe network resistance characteristic curve and the variable given pressure difference characteristic curve.

[0012] Optionally, within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value includes:

[0013] Judging whether the current time point is the end time point of the current period. If so, taking the adjusted set pressure difference value as the set pressure difference value corresponding to the next period; if not, taking the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the current period;

[0014] If a new set pressure difference value is obtained, taking the new set pressure difference value as the adjusted set pressure difference value; if no new set pressure difference value is obtained, taking the set pressure difference value corresponding to the current period as the adjusted set pressure difference value.

[0015] Optionally, within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value includes:

[0016] Obtaining real-time information of the central air-conditioning chilled water system, where the real-time information includes the indoor temperature difference of each room in the service area of the central air-conditioning chilled water system;

[0017] When the current time point is the end time point of the current period, based on the indoor temperature difference, determining a first temperature difference value as measurement information, where the first temperature difference value is the temperature difference of a target sub-region in the service area;

[0018] When the first temperature difference value is greater than a first preset lower limit value, deleting the real-time information and the measurement information, and taking the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next period.

[0019] Optionally, within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value includes:

[0020] When the first temperature difference value is less than or equal to the first preset lower limit value, based on the indoor temperature difference, determining a second temperature difference value as the measurement information, where the second temperature difference value is the average temperature difference of the service area;

[0021] When the second temperature difference value is greater than a second preset lower limit value, deleting the real-time information and the measurement information, and taking the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next period.

[0022] Optionally, within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value includes:

[0023] Obtain the temperature difference between the supply water and return water of each terminal device in the central air-conditioning chilled water system as the real-time information;

[0024] When the second temperature difference value is less than or equal to the second preset lower limit value, based on the temperature difference between the supply water and return water, determine a third temperature difference value as the measured information, where the third temperature difference value is the temperature difference between the supply water and return water of the target terminal device in the central air-conditioning chilled water system;

[0025] When the third temperature difference value is not within the first preset value range, delete the real-time information and the measured information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0026] Optionally, adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value includes:

[0027] When the third temperature difference value is within the first preset value range, based on the indoor temperature difference, determine a fourth temperature difference value as the measured information, where the fourth temperature difference value is the average temperature difference of each terminal device in the central air-conditioning chilled water system;

[0028] When the fourth temperature difference value is not within the second preset value range, delete the real-time information and the measured information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0029] Optionally, adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value includes:

[0030] Detect alarm records, where when the first temperature difference value is not within the first alarm value range, generate a first alarm record, when the second temperature difference value is not within the second alarm value range, generate a second alarm record, and when it is detected that the frequency value of the chilled water pump is not within the third alarm value range, generate a third alarm record;

[0031] When the fourth temperature difference value is within the second preset value range, if a first alarm record, a second alarm record, or a third alarm record is detected, delete the measured information, the real-time information, and each alarm record, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle;

[0032] If no alarm record is detected, use the adjusted set pressure difference value as the set pressure difference value corresponding to the next cycle.

[0033] Another aspect of the present invention provides a control device for a central air-conditioning chilled water system, the device includes:

[0034] An acquisition module for acquiring the set pressure difference of the chilled water system of a central air conditioner;

[0035] An adjustment module for adjusting the set pressure difference within a preset period to obtain an adjusted set pressure difference;

[0036] A control module for controlling the chilled water pump of the chilled water system of the central air conditioner based on the adjusted set pressure difference to adjust the chilled water flow of the chilled water system of the central air conditioner.

[0037] Another aspect of the present invention provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the control method for the chilled water system of the central air conditioner as described in any one of the above.

[0038] Another aspect of the present invention provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, it implements the control method for the chilled water system of the central air conditioner as described in any one of the above.

[0039] The present invention has at least the following beneficial effects:

[0040] The present invention provides a control method, device, equipment and medium for a chilled water system of a central air conditioner. By regularly acquiring the set pressure difference of the chilled water system of the central air conditioner to monitor the current operating state of the chilled water system of the central air conditioner, and adjusting the set pressure difference within a preset period to dynamically set the set pressure difference of the chilled water system of the central air conditioner. Based on the adjusted set pressure difference, the chilled water pump of the chilled water system of the central air conditioner is controlled, so that the chilled water pump of the chilled water system of the central air conditioner can flexibly adapt to the dynamically changing load demand, allowing the chilled water pump to reduce the output power as the load demand decreases, thereby reducing the energy consumption of the chilled water system of the central air conditioner. Compared with operating in a fixed set pressure difference mode, the chilled water system of the central air conditioner in this solution reduces unnecessary chilled water flow and realizes an energy-efficient operating state on the premise of meeting the load demand and ensuring the comfort requirements of users using the central air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings are used to provide a further understanding of the technical solutions of the present invention, and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation to the technical solutions of the present invention.

[0042] Figure 1 It is a flowchart of the steps of a control method for a chilled water system of a central air conditioner;

[0043] Figure 2It is an analysis diagram of differential pressure change characteristics applied in a control method for a central air-conditioning chilled water system;

[0044] Figure 3 It is the first step flowchart of step S102 in a control method for a central air-conditioning chilled water system;

[0045] Figure 4 It is the second step flowchart of step S102 in a control method for a central air-conditioning chilled water system;

[0046] Figure 5 It is the third step flowchart of step S102 in a control method for a central air-conditioning chilled water system;

[0047] Figure 6 It is the fourth step flowchart of step S102 in a control method for a central air-conditioning chilled water system;

[0048] Figure 7 It is the fifth step flowchart of step S102 in a control method for a central air-conditioning chilled water system;

[0049] Figure 8 It is the operation flowchart of a chilled water pump in the application scenario of a control method for a central air-conditioning chilled water system;

[0050] Figure 9 It is a schematic structural diagram of a control device for a central air-conditioning chilled water system;

[0051] Figure 10 It is a schematic structural diagram of an electronic device. Specific implementation manners

[0052] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0053] Before elaborating on the embodiments of the present application in detail, some nouns and terms involved in the embodiments of the present application will be described first. The nouns and terms involved in the embodiments of the present application are applicable to the following explanations.

[0054] The current control methods for central air-conditioning chilled water systems usually have two control strategies: constant temperature difference and constant pressure difference. In the constant pressure difference control strategy, pressure difference (or pressure) sensors are set on the chilled water supply main pipe and the return main pipe. During the operation of the system, the pressure difference between the supply and return main pipes is detected in real time through the sensors, and then the detected pressure difference is compared with the preset pressure difference value, and the difference between the two is used as the basis for controlling the chilled water pump. Specifically, by adjusting the frequency and speed of the chilled water pump, it is ensured that the pressure difference between the supply and return main pipes is accurately maintained at the set pressure difference value, thereby controlling the flow rate of chilled water in the system.

[0055] During the adjustment process of the air-conditioning terminal equipment, the resistance of the system pipe network will change accordingly, resulting in a change in the pressure difference between the supply and return main pipes. This change in pressure difference can represent the change in user load, and the change in pressure difference is more sensitive than the change in temperature difference. Therefore, the constant pressure difference control strategy has its rationality. However, this strategy also has obvious deficiencies. The primary problem lies in how to scientifically preset the pressure difference value of the supply and return main pipes: if it is set only according to the design value, it cannot flexibly respond to the dynamic change of the load, thus limiting the energy-saving effect. And if we try to adjust the set pressure difference value in real time according to the load change, how to set it is still a problem that has not been solved so far.

[0056] The frequent change of the system load may also weaken the dynamic regulation ability of the system. In some cases, it may even cause abnormal water flow at the terminal equipment, which not only affects the stable operation of the equipment but also may have an adverse impact on the comfort of the indoor environment. Due to the above deficiencies, in engineering practice, this control strategy is less used.

[0057] In addition, when the chilled water temperature difference at the terminal equipment of the central air-conditioning chilled water system has been maintained within a certain range, that is, the supply and return water temperature difference of the chilled water in the main pipe of the central air-conditioning chilled water system has also been maintained within a certain range, the traditional constant temperature difference control strategy is no longer applicable, and the constant pressure difference control strategy has obvious deficiencies: at this time, since the required chilled water flow rate at the terminal decreases and the valve opening of the terminal equipment decreases, the pressure difference between the supply and return main pipes will inevitably be higher than the set pressure difference. To maintain the safety of the system, the bypass valve of the supply and return main pipes of the central air-conditioning chilled water system must be adjusted to increase the bypass flow rate, resulting in a great waste of energy, that is, the traditional constant pressure difference regulation strategy is no longer applicable.

[0058] In view of the above analysis, the present invention provides a control method, device, equipment and medium for a central air-conditioning chilled water system. By regularly obtaining the set pressure difference value of the central air-conditioning chilled water system, the current operating state of the central air-conditioning chilled water system is monitored, and within a preset period, the set pressure difference value is adjusted to dynamically set the set pressure difference value of the central air-conditioning chilled water system. Based on the adjusted set pressure difference value, the chilled water pump of the central air-conditioning chilled water system is controlled, so that the chilled water pump of the central air-conditioning chilled water system can flexibly adapt to the dynamically changing load demand, allowing the chilled water pump to reduce the output power as the load demand decreases, thereby reducing the energy consumption of the central air-conditioning chilled water system. Compared with operating in a fixed set pressure difference value mode, the central air-conditioning chilled water system of this solution reduces unnecessary chilled water flow under the premise of meeting the load demand and ensuring the comfort requirements of users using the central air-conditioning, achieving an energy-efficient operating state. In addition, since this solution can flexibly adjust the set pressure difference value of the central air-conditioning chilled water system, when the chilled water flow required at the end decreases and the valve opening of the end equipment decreases, by adjusting the set pressure difference value, it is avoided that the pressure difference between the supply and return main pipes is higher than the set pressure difference value, thereby minimizing the opening time of the pressure difference bypass valve, reducing the bypass flow, and saving energy. Embodiments of the control method, device, equipment and medium for the central air-conditioning chilled water system provided by the present invention are as follows:

[0059] Please refer to Figure 1 , Figure 1 which is a flowchart of the steps of a control method for a central air-conditioning chilled water system.

[0060] In a first aspect, this embodiment provides a control method for a central air-conditioning chilled water system, and the method includes:

[0061] S101. Obtain the set pressure difference value of the central air-conditioning chilled water system.

[0062] S102. Adjust the set pressure difference value within a preset period to obtain an adjusted set pressure difference value.

[0063] S103. Based on the adjusted set pressure difference value, control the chilled water pump of the central air-conditioning chilled water system to adjust the chilled water flow of the central air-conditioning chilled water system.

[0064] In some embodiments, after sending the adjusted set pressure difference value to the central air-conditioning chilled water system, the central air-conditioning chilled water system changes the set pressure difference value of its system to the adjusted set pressure difference value and detects the pipeline pressure difference of the central air-conditioning chilled water system. According to the difference between the pipeline pressure difference and the adjusted set pressure difference value, the frequency and speed of the chilled water pump are adjusted to make the pipeline pressure difference tend to the set pressure difference value, thereby controlling the chilled water flow in the system.

[0065] In some embodiments, when it is detected that the communication is in an abnormal state, the adjustment of the set pressure difference value is stopped, and the adjusted set pressure difference value is deleted, so that the set pressure difference value of the central air-conditioning chilled water system is changed to a preset set pressure difference value.

[0066] It can be understood that the communication abnormal state can be a state of disconnection from the central air-conditioning chilled water system or a state of communication delay with the central air-conditioning chilled water system.

[0067] In this embodiment, when the communication is in a normal state, the set pressure difference value of the central air-conditioning chilled water system can be normally obtained, and the chilled water pump of the central air-conditioning chilled water system can be controlled. When the communication is in an abnormal state, the set pressure difference value of the central air-conditioning chilled water system is changed to a preset set pressure difference value, and it continues to operate in the original manner to ensure the normal operation of the central air-conditioning chilled water system and guarantee safety and stability.

[0068] In some embodiments, when adjusting the set pressure difference value, according to the optimal working area of the chilled water pump and the fuzzy PID algorithm in the preset pressure difference change characteristic analysis diagram, the target set pressure difference value is determined and used as the adjusted set pressure difference value. Among them, based on the pump characteristic curve, the pipe network resistance characteristic curve and the variable given pressure difference characteristic curve, a pressure difference change characteristic analysis diagram is generated.

[0069] Please refer to Figure 2 , as can be seen from the pressure difference change characteristic analysis diagram, at partial load, the working point of the chilled water pump and the supply and return water pressure difference move up. Considering the operating safety and stability of the system, the working point of the chilled water pump should be maintained at a working frequency of 30 Hz and above 10% of the minimum load required by the host. Therefore, the optimal working area of the chilled water pump can be obtained.

[0070] For example, in a specific embodiment, the set pressure difference value is DPs, the target set pressure difference value is DPn, DPn = DPs + ΔP, where ΔP is the adjustment amplitude. After calculating DPn, the new set pressure difference value DPn is obtained. After adjusting the set pressure difference value, the new set pressure difference value DPn is sent to the chilled water pump controller, and the chilled water pump operates in a constant pressure difference mode according to the new pressure difference value DPn, thereby controlling the working frequency of the chilled water pump.

[0071] It can be understood that in a specific application scenario, when the central air-conditioning chilled water system adopts the terminal constant temperature difference regulation mode, under the same load conditions, due to the gradual increase in temperature difference, according to the heat calculation formula, the required chilled water flow rate gradually decreases, the water valve opening of the terminal equipment in the central air-conditioning chilled water system gradually decreases, and the system resistance increases. In the situation where the main pipe pressure difference remains constant, if other adjustment measures are not considered, the pressure difference bypass valve will increase its opening due to the increase in system resistance to balance the pressure difference. Although this can maintain the system stability, it is accompanied by a significant increase in the bypass flow rate. A large amount of chilled water directly returns to the unit through the pressure difference bypass valve without being effectively utilized, resulting in a significant energy waste phenomenon.

[0072] In view of the above situation in the specific application scenario, as the required chilled water flow rate at the terminal decreases, to effectively curb this energy waste trend, according to the above Figure 2 As shown, on the variable given pressure difference characteristic curve, the operating point of the chilled water pump moves to the left as the flow rate decreases. During this process, the control frequency of the chilled water pump is also dynamically adjusted downward to precisely match the system demand, ensuring that while reducing the chilled water flow rate, unnecessary bypass flow rate of the system is not increased, reducing energy waste.

[0073] To precisely respond to this change, when the chilled water flow rate in the central air-conditioning chilled water system decreases, according to the optimal operating area of the chilled water pump and the fuzzy PID control algorithm in the preset pressure difference change characteristic analysis diagram, the set pressure difference value of the central air-conditioning chilled water system is dynamically adjusted. Through this intelligent adjustment strategy, the set pressure difference value of the central air-conditioning chilled water system no longer remains at a fixed value, but dynamically sets a changing range according to actual needs. It not only considers the safety and stability of the air-conditioning system but also obtains high energy-saving benefits, achieving energy conservation and optimized operation of the system.

[0074] In some embodiments, step S102 includes:

[0075] Judge whether the current time point is the end time point of the current cycle. If so, use the adjusted set pressure difference value as the set pressure difference value corresponding to the next cycle. If not, use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the current cycle; if a new set pressure difference value is obtained, use the new set pressure difference value as the adjusted set pressure difference value. If no new set pressure difference value is obtained, use the set pressure difference value corresponding to the current cycle as the adjusted set pressure difference value.

[0076] In this embodiment, by automatically calculating the end time point of the cycle, periodic adjustment of the set pressure difference value is achieved. After the user only inputs the preset set pressure difference value, the subsequent calculation and adjustment processes are all automatically carried out adaptively without manual intervention, with high automation and practicability.

[0077] Please refer to Figure 3 , Figure 3 which is the first step flowchart of step S102 in a control method for a central air-conditioning chilled water system.

[0078] In some embodiments, step S102 includes:

[0079] S201. Obtain real-time information of the central air-conditioning chilled water system, where the real-time information includes the indoor temperature difference of each room in the service area of the central air-conditioning chilled water system.

[0080] S202. When the current time point is the end time point of the current cycle, based on the indoor temperature difference, determine a first temperature difference value as the measurement information, where the first temperature difference value is the temperature difference of the target sub-area in the service area.

[0081] S203. When the first temperature difference value is greater than the first preset lower limit value, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0082] In some embodiments, the indoor temperature difference is equal to the difference between the actual temperature and the set temperature in the room.

[0083] Please refer to Figure 4 , Figure 4 which is the second step flowchart of step S102 in a control method for a central air-conditioning chilled water system.

[0084] In some embodiments, step S102 includes:

[0085] S301. When the first temperature difference value is less than or equal to the first preset lower limit value, based on the indoor temperature difference, determine a second temperature difference value as the measurement information, where the second temperature difference value is the average temperature difference of the service area.

[0086] S302. When the second temperature difference value is greater than the second preset lower limit value, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0087] In some embodiments, when determining the second temperature difference value, obtain the indoor temperature difference of each room, and calculate the average temperature difference of the service area according to the preset coefficient of each room; when determining the first temperature difference value, calculate the temperature difference of the target sub-area according to the weight ratio between the target sub-area and the service area.

[0088] Please refer to Figure 5 , Figure 5 which is the third step flowchart of step S102 in a control method for a central air-conditioning chilled water system.

[0089] In some embodiments, step S102 includes:

[0090] S401. Obtain the temperature difference between the supply water and return water of each terminal device in the central air-conditioning chilled water system as real-time information.

[0091] S402. When the second temperature difference value is less than or equal to the second preset lower limit value, determine a third temperature difference value based on the temperature difference between the supply water and return water as measurement information, where the third temperature difference value is the temperature difference between the supply water and return water of the target terminal device in the central air-conditioning chilled water system.

[0092] S403. When the third temperature difference value is not within the first preset value range, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0093] Please refer to Figure 6 , Figure 6 which is the flowchart of the fourth step of step S102 in a control method for a central air-conditioning chilled water system.

[0094] In some embodiments, step S102 includes:

[0095] S501. When the third temperature difference value is within the first preset value range, determine a fourth temperature difference value based on the indoor temperature difference as measurement information, where the fourth temperature difference value is the average temperature difference of each terminal device in the central air-conditioning chilled water system.

[0096] S502. When the fourth temperature difference value is not within the second preset value range, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

[0097] In some embodiments, when determining the third temperature difference value, obtain the temperature difference between the supply water and return water of each terminal device in the central air-conditioning chilled water system, and calculate the average temperature difference of each terminal device in the central air-conditioning chilled water system according to the preset coefficient of each room; when determining the fourth temperature difference value, calculate the temperature difference between the supply water and return water of the target terminal device according to the weight ratio between the target sub-region and the service region.

[0098] Please refer to Figure 7 , Figure 7 which is the flowchart of the fifth step of step S102 in a control method for a central air-conditioning chilled water system.

[0099] In some embodiments, step S102 includes:

[0100] S601. Detect alarm records, wherein a first alarm record is generated when the first temperature difference value is not within the first alarm value range, a second alarm record is generated when the second temperature difference value is not within the second alarm value range, and a third alarm record is generated when it is detected that the frequency value of the chilled water pump is not within the third alarm value range.

[0101] S602. When the fourth temperature difference value is within the second preset value range, if the first alarm record, the second alarm record or the third alarm record is detected, the alarm record, the real-time information and the measurement information are deleted, and the set pressure difference value is used as the set pressure difference value corresponding to the next cycle, wherein the set pressure difference value is the set pressure difference value of the central air-conditioning chilled water system.

[0102] S603: If no alarm record is detected, the adjusted set pressure difference value is used as the set pressure difference value corresponding to the next cycle.

[0103] It can be understood that the above embodiment avoids the situation where the system pressure difference is significantly higher than the set pressure difference by automatically adjusting the pressure difference set value, and also eliminates the phenomenon that a large amount of chilled water directly flows back to the unit through the pressure difference bypass valve, thereby significantly reducing the system energy consumption and significantly saving energy. What is more important is that this optimized energy-saving process does not affect the comfort of end users, but responds to load changes in real time, accurately controls the chilled water flow, and meets the actual needs of end users.

[0104] See also Figure 8 , Figure 8 A specific embodiment of a central air-conditioning chilled water system control method applied in an actual scenario is shown.

[0105] In this embodiment, when the central air-conditioning chilled water system is in the initial state (after startup), the set pressure difference value of the central air-conditioning chilled water system is set to DPs; after the system operates normally, the chilled water pump operates according to the set pressure difference value, and the set pressure difference value of the central air-conditioning chilled water system obtained is DPs; considering the system stability and safety issues, the communication status is judged within a preset period.

[0106] If the communication is normal, determine whether the current time point has reached the end time point of the cycle (cycle duration 10-30min, this parameter is configurable). If not, the set differential pressure value corresponding to the current cycle is still DPs. If it is reached, determine whether a new set differential pressure value has been issued. If no new set differential pressure value has been issued, use the set differential pressure value DPs as the adjusted set differential pressure value, and the chilled water pump will still operate according to the set differential pressure value DPs in the next cycle; if a new differential pressure value has been issued, the new set differential pressure value is DPn, use the set differential pressure value DPn as the adjusted set differential pressure value, and the chilled water pump will still operate according to the set differential pressure value DPn in the next cycle.

[0107] If in a communication abnormal state, clear the current set pressure difference value DPn, restore the set pressure difference value of the system to DPs, and ensure the normal operation of the chilled water pump when it is offline from the system platform communication.

[0108] In an embodiment of a control method for a central air-conditioning chilled water system applied in an actual scenario, first, according to factors such as the enclosure structure load, terminal equipment load, and change in the number of personnel in each room, configure the cooling / heating weight coefficient Ki for each room. Select 1-5 rooms in the service area and set the sub-areas where these rooms are located as the most unfavorable point areas, that is, the target sub-areas. Configure the weight ratio for the most unfavorable point area, configure the minimum set temperature difference lower limit value ΔTrzmin and the supply-return water temperature difference set value ΔTdzset for the most unfavorable point area. Configure the comprehensive minimum set temperature difference lower limit value ΔTrpmin and the supply-return water temperature difference set value ΔTdpset for all rooms in the service area.

[0109] Then, start the central air-conditioning chilled water system, set the pressure difference value of the chilled water main pipe to the preset set pressure difference value DPs, set the minimum operating frequency Fmin of the chilled water pump, and set the room temperature alarm record Wri, the supply-return water alarm record Wdi of the terminal equipment, and the chilled water pump alarm record WFi.

[0110] After the system operates normally, collect the indoor temperature Tr and the set temperature Ts of each room in the service area in real time, calculate the difference between the two and use it as the indoor temperature difference value ΔTri. When ΔTri is not within the first alarm value range, generate a first alarm record Wri; and upload and save the indoor temperature difference value ΔTri and the first alarm record Wri of each room through the standard communication bus and the standard communication protocol.

[0111] Collect the supply-return water temperature difference ΔTdi of each terminal equipment in the central air-conditioning chilled water system in real time. When ΔTdi is not within the second alarm value range, generate a second alarm record Wdi, and upload and save the supply-return water temperature difference ΔTdi and the second alarm record Wdi through the standard communication bus and the standard communication protocol.

[0112] Collect the operating frequency Fi of the chilled water pump in real time. When Fi is not within the third alarm value range, generate a third alarm record WFi, and upload and save the operating frequency Fi and the third alarm record WFi through the standard communication bus and the standard communication protocol.

[0113] Summarize the indoor temperature difference value ΔTri of each room, calculate the comprehensive area weighted average value ΔTrp as the average temperature difference of the service area according to the cooling / heating weight coefficient Ki of each room, and calculate the set difference ΔTrz of the most unfavorable point as the temperature difference of the target sub-area according to the weight ratio of the most unfavorable point area.

[0114] Summarize the supply - return water temperature difference ΔTdi of each terminal device, calculate the comprehensive regional weighted average value ΔTdp as the average temperature difference of each terminal device in the central air - conditioning chilled water system according to the cooling / heating weight coefficient Ki of each room, and calculate the supply - return water temperature difference ΔTdz at the most unfavorable point as the supply - return water temperature difference of the target terminal device according to the weight ratio of the most unfavorable point area.

[0115] Judge whether it reaches the end time point of the cycle (10 - 30 min, this parameter can be configured). If not, maintain the set pressure difference value corresponding to the current cycle.

[0116] If it reaches, first judge whether the set difference value ΔTrz at the most unfavorable point is less than or equal to the lower limit value ΔTrzmin. If not, clear each calculated value obtained from the above steps and the above alarm records, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0117] If the set difference value ΔTrz at the most unfavorable point is less than or equal to the lower limit value ΔTrzmin, then judge whether the weighted average set difference value ΔTrp of the comprehensive area is less than or equal to the lower limit value ΔTrpmin. If so, clear each calculated value obtained from the above steps and the above alarm records, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0118] If the weighted average set difference value ΔTrp of the comprehensive area is less than or equal to the lower limit value ΔTrpmin, then judge whether the supply - return water temperature difference ΔTdz at the most unfavorable point is within the set value range of ΔTdzset (5℃ ± 10%). If not, clear each calculated value obtained from the above steps and the above alarm records, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0119] If the supply - return water temperature difference ΔTdz at the most unfavorable point is within the set value range of ΔTdzset, then judge whether the supply - return water temperature difference ΔTdp of the comprehensive area is within the set value range of ΔTdpset (for example, 5℃ ± 10%). If not, clear each calculated value obtained from the above steps and the above alarm records, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0120] If it is judged whether the supply - return water temperature difference ΔTdp of the comprehensive area is within the set value range of ΔTdpset, then detect the alarm records of each terminal device. If any alarm records Wri, Wdi, and WFi are detected, clear each calculated value obtained from the above steps and the above alarm records, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0121] If no alarm record is detected, the optimal working area of the chilled water pump and the fuzzy PID algorithm are analyzed according to the preset differential pressure change characteristic analysis diagram, and a new set differential pressure value DPn = DPs + ΔP is calculated.

[0122] The new set differential pressure value DPn is sent to the controller of the chilled water pump, so that the chilled water pump in the constant differential pressure mode adjusts the operation frequency of the chilled water pump according to the new set differential pressure value until the next adjustment cycle.

[0123] Reference Figure 9 , Figure 9 is a structural schematic diagram of a control device for a central air-conditioning chilled water system.

[0124] In a second aspect, the present embodiment provides a control device for a central air-conditioning chilled water system, and the device includes:

[0125] An acquisition module 701, configured to acquire the set differential pressure value of the central air-conditioning chilled water system.

[0126] An adjustment module 702, configured to adjust the set differential pressure value within a preset period to obtain an adjusted set differential pressure value.

[0127] A control module 703, configured to control the chilled water pump of the central air-conditioning chilled water system based on the adjusted set differential pressure value to adjust the chilled water flow rate of the central air-conditioning chilled water system.

[0128] Those of ordinary skill in the art can understand that all or some of the steps and devices disclosed in the above methods can be implemented as software, firmware, hardware, and their appropriate combinations. Some physical components or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cartridges, tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. It is well known to those of ordinary skill in the art that communication media typically contains computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery medium.

[0129] It can be understood that the content in the above method embodiments is applicable to the device embodiments of the present application. The functions specifically implemented by the device embodiments of the present application are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method embodiments.

[0130] In a third aspect, an embodiment of the present application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the central air-conditioning chilled water system control method as described in any one of the above.

[0131] Reference Figure 10 , Figure 10 schematically shows the hardware structure of an electronic device according to another embodiment. The electronic device includes:

[0132] A processor 801, which can be implemented in a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, etc., and is used to execute relevant programs to implement the technical solutions provided by the embodiments of the present application;

[0133] A memory 802, which may be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM), etc. The memory 802 can store an operating device and other application programs. When implementing the technical solutions provided in the embodiments of this specification through software or firmware, the relevant program codes are stored in the memory 802 and are called by the processor 801 to execute the central air-conditioning chilled water system control method in the embodiments of this application;

[0134] An input / output interface 803, which is used to implement information input and output;

[0135] A communication interface 804, which is used to implement communication interaction between this device and other devices. Communication can be achieved through a wired manner (such as USB, network cable, etc.) or through a wireless manner (such as mobile network, WIFI, Bluetooth, etc.);

[0136] A bus 805, which transmits information between various components of the device (such as the processor 801, the memory 802, the input / output interface 803, and the communication interface 804);

[0137] Among them, the processor 801, the memory 802, the input / output interface 803, and the communication interface 804 are communicatively connected to each other inside the device through the bus 805.

[0138] It can be understood that the content in the above method embodiments is applicable to the embodiments of this electronic device. The functions specifically implemented by the embodiments of this electronic device are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those in the above method embodiments.

[0139] In a fourth aspect, the embodiments of this application provide a computer-readable storage medium, in which there is a program executable by a processor. When the program executable by the processor is executed by the processor, it is used to implement the central air-conditioning chilled water system control method described in any one of the above specific embodiments.

[0140] The embodiments of this application also disclose a computer program product, including a computer program or computer instructions. The computer program or computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer program or computer instructions from the computer-readable storage medium, and the processor executes the computer program or computer instructions, so that the computer device executes the central air-conditioning chilled water system control method described in any of the previous embodiments.

[0141] It can be understood that the content in the above method embodiments is applicable to the present storage medium embodiment. The functions specifically implemented by the present storage medium embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those of the above method embodiments.

[0142] In the above embodiments, there is no need to modify the hardware equipment of the refrigeration unit. It can be achieved only by collecting and transmitting the pressure difference value through the platform software system. This greatly reduces the implementation cost and can quickly generate energy-saving economic benefits, having significant advantages in the transformation and upgrading of the central air-conditioning system.

[0143] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices. It should be understood that in the present application, "at least one (item)" refers to one or more, and "a plurality" refers to two or more.

[0144] In several embodiments provided by the present application, it should be understood that the disclosed devices, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be an indirect coupling or communication connection through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0145] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0146] In addition, in each embodiment of the present application, the functional units can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0147] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memory (ROM for short), random access memory (RAM for short), magnetic disks, or optical discs.

[0148] Although the description of the present application has been quite detailed and several of the described embodiments have been described in particular, it is not intended to be limited to any of these details or embodiments or any particular embodiment, but rather should be regarded as effectively covering the intended scope of the present application by referring to the appended claims and considering the broad possibilities of interpretation of these claims in light of the prior art. In addition, the present application has been described above with embodiments foreseeable by the inventors for the purpose of providing a useful description, and those non-substantive modifications to the present application that are not currently foreseeable can still represent equivalent modifications of the present application.

Claims

1. A control method for a central air-conditioning chilled water system, characterized in that The method includes: Obtaining the set pressure difference value of the central air-conditioning chilled water system; Adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value; Obtaining the real-time information of the central air-conditioning chilled water system, where the real-time information includes the indoor temperature difference of each room in the service area of the central air-conditioning chilled water system, and the indoor temperature difference is equal to the difference between the actual temperature and the set temperature in the room; When the current time point is the end time point of the current period, determining a first temperature difference value as the measurement information based on the indoor temperature difference, where the first temperature difference value is the temperature difference of the target sub-area in the service area. When determining the first temperature difference value, calculate the temperature difference of the target sub-area according to the weight ratio between the target sub-area and the service area; When the first temperature difference value is greater than a first preset lower limit value, deleting the real-time information and the measurement information, and using the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next period; When the first temperature difference value is less than or equal to the first preset lower limit value, determining a second temperature difference value as the measurement information based on the indoor temperature difference, where the second temperature difference value is the average temperature difference of the service area. When determining the second temperature difference value, obtain the indoor temperature difference of each room and calculate the average temperature difference of the service area according to the preset coefficient of each room; When the second temperature difference value is greater than a second preset lower limit value, deleting the real-time information and the measurement information, and using the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next period; Controlling the chilled water pump of the central air-conditioning chilled water system based on the adjusted set pressure difference value to adjust the chilled water flow of the central air-conditioning chilled water system.

2. The control method of a central air-conditioning chilled water system according to claim 1, characterized in that, The method includes: When it is detected that the communication is in an abnormal state, stopping adjusting the set pressure difference value and deleting the adjusted set pressure difference value, so that the set pressure difference value of the central air-conditioning chilled water system is changed to a preset set pressure difference value.

3. A control method for a central air-conditioning chilled water system according to claim 1, characterized in that The method includes: When adjusting the set pressure difference value, determining a target set pressure difference value as the adjusted set pressure difference value according to the optimal working area of the chilled water pump in the preset pressure difference change characteristic analysis diagram and the preset fuzzy PID algorithm, where the pressure difference change characteristic analysis diagram is generated based on the pump characteristic curve, the pipe network resistance characteristic curve, and the variable given pressure difference characteristic curve.

4. A control method for a central air-conditioning chilled water system according to claim 1, characterized in that, The adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Judging whether the current time point is the end time point of the current period. If so, using the adjusted set pressure difference value as the set pressure difference value corresponding to the next period. If not, using the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the current period; If a new set pressure difference value is obtained, use the new set pressure difference value as the adjusted set pressure difference value. If a new set pressure difference value is not obtained, use the set pressure difference value corresponding to the current cycle as the adjusted set pressure difference value.

5. A control method for a central air-conditioning chilled water system according to claim 1, characterized in that, Adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value includes: Obtaining the temperature difference between the supply water and return water of each terminal device in the central air-conditioning chilled water system and using it as the real-time information; When the second temperature difference value is less than or equal to the second preset lower limit value, based on the temperature difference between the supply water and return water, determine a third temperature difference value and use it as the measurement information, where the third temperature difference value is the temperature difference between the supply water and return water of the target terminal device in the central air-conditioning chilled water system; When determining the third temperature difference value, obtain the temperature difference between the supply water and return water of each terminal device in the central air-conditioning chilled water system, and calculate the average temperature difference of each terminal device in the central air-conditioning chilled water system according to the preset coefficient of each room; When the third temperature difference value is not within the first preset value range, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

6. A control method for a central air-conditioning chilled water system according to claim 5, characterized in that, Adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value includes: When the third temperature difference value is within the first preset value range, based on the indoor temperature difference, determine a fourth temperature difference value and use it as the measurement information, where the fourth temperature difference value is the average temperature difference of each terminal device in the central air-conditioning chilled water system; When determining the fourth temperature difference value, calculate the temperature difference between the supply water and return water of the target terminal device according to the weight ratio between the target sub-region and the service region; When the fourth temperature difference value is not within the second preset value range, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

7. A control method for a central air-conditioning chilled water system according to claim 6, characterized in that, Adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value includes: Detecting alarm records, where when the first temperature difference value is not within the first alarm value range, generating a first alarm record, when the second temperature difference value is not within the second alarm value range, generating a second alarm record, and when it is detected that the frequency value of the chilled water pump is not within the third alarm value range, generating a third alarm record; When the fourth temperature difference value is within the second preset value range, if a first alarm record, a second alarm record, or a third alarm record is detected, delete the measurement information, the real-time information, and each alarm record, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle; If no alarm record is detected, use the adjusted set pressure difference value as the set pressure difference value corresponding to the next cycle.

8. A control device for a central air-conditioning chilled water system, characterized in that, The device includes: An acquisition module for acquiring the set pressure difference value of the central air-conditioning chilled water system; An adjustment module for adjusting the set pressure difference value within a preset cycle to obtain an adjusted set pressure difference value; A control module, configured to control a chilled water pump of the central air-conditioning chilled water system based on the adjusted set pressure difference value, so as to adjust the chilled water flow rate of the central air-conditioning chilled water system; The adjustment module is further configured to: Obtain real-time information of the central air-conditioning chilled water system, where the real-time information includes the indoor temperature difference of each room in the service area of the central air-conditioning chilled water system, and the indoor temperature difference is equal to the difference between the actual temperature and the set temperature in the room; When the current time point is the end time point of the current cycle, based on the indoor temperature difference, determine a first temperature difference value as the measurement information, where the first temperature difference value is the temperature difference of the target sub-area in the service area, and when determining the first temperature difference value, calculate the temperature difference of the target sub-area according to the weight ratio between the target sub-area and the service area; When the first temperature difference value is greater than a first preset lower limit value, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle; When the first temperature difference value is less than or equal to the first preset lower limit value, based on the indoor temperature difference, determine a second temperature difference value as the measurement information, where the second temperature difference value is the average temperature difference of the service area, and when determining the second temperature difference value, obtain the indoor temperature difference of each room, and calculate the average temperature difference of the service area according to the preset coefficient of each room; When the second temperature difference value is greater than a second preset lower limit value, delete the real-time information and the measurement information, and use the set pressure difference value of the central air-conditioning chilled water system as the set pressure difference value corresponding to the next cycle.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory stores a computer program, and when the processor executes the computer program, it implements the central air-conditioning chilled water system control method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the central air-conditioning chilled water system control method according to any one of claims 1 to 7.

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