Control method, device and equipment for chilled water system of central air conditioner and medium

Abstract

The invention is mainly used in the technical field of refrigerators and central air conditioners. The invention discloses a control method, device and equipment for a chilled water system of a central air conditioner and a medium. The method comprises the steps that the set pressure difference value of the chilled water system of the central air conditioner is obtained; in a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value; and controlling a chilled water pump of the chilled water system of the central air conditioner on the basis of the adjusted set pressure difference value so as to adjust the chilled water flow of the chilled water system of the central air conditioner. The energy consumption of the chilled water system of the central air conditioner can be reduced.

Description

Technical Field

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

[0002] With the improvement of my country'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 energy consumption of buildings, and its energy consumption plays a pivotal role in the total energy consumption of buildings. This means that while pursuing a comfortable environment, a huge energy price 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 pay attention to. Summary of the invention

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

[0004] The present invention provides a central air-conditioning chilled water system control method, the method comprising: Get the set pressure difference value of the central air-conditioning chilled water system; Within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value; Based on the adjusted set pressure difference value, the chilled water pump of the central air-conditioning chilled water system is controlled to adjust the chilled water flow of the central air-conditioning chilled water system.

[0005] Optionally, the central air-conditioning chilled water system control method includes: When it is detected that the communication is abnormal, 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.

[0006] Optionally, the central air-conditioning chilled water system control method includes: When the set pressure difference value is adjusted, the target set pressure difference value is determined and used 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 pipeline resistance characteristic curve and the variable given pressure difference characteristic curve.

[0007] Optionally, the setting pressure difference value is adjusted within a preset period to obtain an adjusted setting pressure difference value, including: Determine 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, the new set pressure difference value is used as the adjusted set pressure difference value; if no new set pressure difference value is obtained, the set pressure difference value corresponding to the current cycle is used as the adjusted set pressure difference value.

[0008] Optionally, adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Acquire real-time information of the central air-conditioning chilled water system, wherein the real-time information includes the indoor temperature difference of each room in the service area of ​​the central air-conditioning chilled water system; When the current time point is the end time point of the current cycle, based on the indoor temperature difference, a first temperature difference value is determined as the measurement information, wherein the first temperature difference value is a temperature difference value of a target sub-area in the service area; When the first temperature difference value is greater than a first preset lower limit value, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0009] Optionally, adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: When the first temperature difference is less than or equal to the first preset lower limit, a second temperature difference is determined based on the indoor temperature difference and used as the measurement information, wherein the second temperature difference is an average temperature difference of the service area; When the second temperature difference value is greater than a second preset lower limit value, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0010] Optionally, adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Obtaining the supply and return water temperature difference of each terminal device in the central air-conditioning chilled water system as the real-time information; When the second temperature difference is less than or equal to the second preset lower limit, a third temperature difference is determined based on the supply and return water temperature difference and used as the measurement information, wherein the third temperature difference is the supply and return water temperature difference of the target terminal device in the central air-conditioning chilled water system; When the third temperature difference value is not within the first preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0011] Optionally, adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: When the third temperature difference is within the first preset value range, a fourth temperature difference is determined based on the indoor temperature difference and used as the measurement information, wherein the fourth temperature difference is an average temperature difference of each terminal device in the central air-conditioning chilled water system; When the fourth temperature difference value is not within the second preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0012] Optionally, adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Detecting alarm records, wherein when the first temperature difference value is not within a first alarm value range, a first alarm record is generated, when the second temperature difference value is not within a second alarm value range, a second alarm record is generated, and when it is detected that the frequency value of the chilled water pump is not within a third alarm value range, a third alarm record is generated; 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 measurement information, the real-time information and each of the alarm records are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle; 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.

[0013] Another aspect of the present invention provides a central air-conditioning chilled water system control device, the device comprising: An acquisition module is used to obtain a set pressure difference value of a central air-conditioning chilled water system; An adjusting module, used for adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value; The control module is used to control 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.

[0014] Another aspect of the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the central air-conditioning chilled water system control method as described in any one of the above items when executing the computer program.

[0015] Another aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the central air-conditioning chilled water system control method as described in any one of the above items is implemented.

[0016] The present invention has at least the following beneficial effects: The present invention provides a central air-conditioning chilled water system control method, device, equipment and medium. The set differential pressure value of the central air-conditioning chilled water system is obtained regularly to monitor the current operation state of the central air-conditioning chilled water system, and the set differential pressure value is adjusted within a preset period to achieve dynamic setting of the set differential pressure value of the central air-conditioning chilled water system. Based on the adjusted set differential pressure 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 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 differential pressure value mode, the central air-conditioning chilled water system of this solution reduces unnecessary chilled water flow and achieves an efficient and energy-saving operation state under the premise of meeting the load demand and ensuring the comfort requirements of users using the central air conditioner. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

[0018] Figure 1 It is a flow chart of steps of a method for controlling a central air-conditioning chilled water system; Figure 2 It is a pressure difference variation characteristic analysis diagram used in the central air conditioning chilled water system control method; Figure 3 It is a first step flow chart of step S102 in a central air conditioning chilled water system control method; Figure 4 is a flow chart of the second step of step S102 in the central air-conditioning chilled water system control method; Figure 5 is a flow chart of the third step of step S102 in the central air-conditioning chilled water system control method; Figure 6is a flow chart of the fourth step of step S102 in the central air conditioning chilled water system control method; Figure 7 is a fifth step flow chart of step S102 in a central air conditioning chilled water system control method; Figure 8 It is an operation flow chart of a chilled water pump in an application scenario of a central air-conditioning chilled water system control method; Fig. 9 It is a structural schematic diagram of a central air-conditioning chilled water system control device; Fig.10 The figure is a schematic diagram of the structure of an electronic device. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with 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.

[0020] Before describing the embodiments of the present application in detail, some nouns and terms involved in the embodiments of the present application are first described. The nouns and terms involved in the embodiments of the present application are subject to the following explanations.

[0021] 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, a pressure difference (or pressure) sensor is installed on the chilled water supply main and return main. During the operation of the system, the pressure difference between the supply and return mains is detected in real time by the sensor, 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, the pressure difference between the supply and return mains is ensured to be accurately maintained at the set pressure difference value, thereby controlling the flow of chilled water in the system.

[0022] 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 of the supply and return water mains. This pressure difference change can represent the change in user load, and the pressure difference change is more sensitive than the temperature difference change. Therefore, the fixed pressure difference control strategy is reasonable. However, this strategy also has obvious shortcomings. The primary difficulty lies in how to scientifically preset the pressure difference value of the supply and return water mains: if it is set only based on the design value, it will not be able to flexibly respond to the dynamic changes in the load, thereby limiting the energy-saving effect. If you try to adjust the set pressure difference value in real time according to the load change, how to set it? These problems have not been solved yet.

[0023] Frequent changes in system load may also weaken the system's dynamic adjustment ability, and in some cases even lead to abnormal water flow in the terminal equipment, which not only affects the stable operation of the equipment, but also may have an adverse effect on the comfort of the indoor environment. In view of the above shortcomings, this control strategy is rarely used in engineering practice.

[0024] In addition, when the temperature difference of the chilled water in 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 is also 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 shortcomings: at this time, due to the reduction of the chilled water flow required by the terminal, the valve opening of the terminal equipment is reduced, and the pressure difference of the supply and return water main pipe will inevitably be higher than the set pressure difference. In order to maintain system safety, the bypass valve of the supply and return water main pipe of the central air-conditioning chilled water system must be adjusted to increase the bypass flow, resulting in a huge waste of energy. That is, the traditional constant pressure difference adjustment strategy is no longer applicable.

[0025] In view of the above analysis, the present invention provides a central air-conditioning chilled water system control method, device, equipment and medium, which monitors the current operating state of the central air-conditioning chilled water system by regularly acquiring the set pressure difference value of the central air-conditioning chilled water system, and adjusts the set pressure difference value within a preset period to achieve dynamic setting of 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 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 mode, the central air-conditioning chilled water system of this solution reduces unnecessary chilled water flow and achieves an efficient and energy-saving operating state under the premise of meeting the load demand and ensuring the comfort requirements of users using the central air conditioner. In addition, since the scheme can flexibly adjust the set pressure difference value of the central air-conditioning chilled water system, when the chilled water flow required by the terminal decreases and the terminal device valve opening decreases, the set pressure difference value is adjusted to avoid the pressure difference of the supply and return water main pipe being 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. The embodiments of the central air-conditioning chilled water system control method, device, equipment and medium provided by the present invention are as follows: Please refer to Figure 1 , Figure 1 The invention is a flow chart of steps of a central air-conditioning chilled water system control method.

[0026] In a first aspect, this embodiment provides a central air-conditioning chilled water system control method, the method comprising: S101. Obtain a set pressure difference value of a central air-conditioning chilled water system.

[0027] S102: within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value.

[0028] 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.

[0029] In some embodiments, after the adjusted set differential pressure value is sent to the central air-conditioning chilled water system, the central air-conditioning chilled water system changes the set differential pressure value of its system to the adjusted set differential pressure value, and detects the differential pressure value of the pipeline of the central air-conditioning chilled water system. According to the difference between the differential pressure value of the pipeline and the adjusted set differential pressure value, the frequency and speed of the chilled water pump are adjusted so that the differential pressure value of the pipeline approaches the set differential pressure value, thereby controlling the chilled water flow in the system.

[0030] In some embodiments, when a communication abnormality is detected, 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.

[0031] It can be understood that the abnormal communication 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.

[0032] In this embodiment, when the communication is normal, the set pressure difference value of the central air-conditioning chilled water system can be obtained normally, and the chilled water pump of the central air-conditioning chilled water system can be controlled. When the communication is abnormal, the set pressure difference value of the central air-conditioning chilled water system is changed to the preset set pressure difference value, and the original mode is used to continue to operate, ensuring the normal operation of the central air-conditioning chilled water system, and ensuring safety and stability.

[0033] In some embodiments, when the set pressure difference value is adjusted, the target set pressure difference value is determined and used as the adjusted set pressure difference value based on the optimal working area of ​​the chilled water pump in the preset pressure difference change characteristic analysis diagram and the fuzzy PID algorithm, wherein the pressure difference change characteristic analysis diagram is generated based on the water pump characteristic curve, the pipeline resistance characteristic curve and the variable given pressure difference characteristic curve.

[0034] See also Figure 2 From the pressure difference change characteristic analysis diagram, it can be seen that at partial load, the operating point of the chilled water pump and the supply and return water pressure difference move up. Considering the operation safety and stability of the system, the operating point of the chilled water pump should be maintained at an operating frequency of 30Hz and above the minimum load required by the host by 10%. Therefore, the optimal working area of ​​the chilled water pump can be obtained.

[0035] For example, in a specific embodiment, the set pressure difference value is DPs, the target set pressure difference value is DPn, DPn=DPs+ΔP, ΔP is the adjustment amplitude, and the new set pressure difference value DPn is obtained after calculating DPn. After the set pressure difference value is adjusted, the new set pressure difference value DPn is sent to the chilled water pump controller, and the chilled water pump runs the constant pressure difference mode according to the new pressure difference value DPn, thereby controlling the working frequency of the chilled water pump.

[0036] It is understandable that in a specific application scenario, when the central air-conditioning chilled water system adopts the terminal constant temperature difference adjustment 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 of 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 system stability, it is accompanied by a significant increase in bypass flow. A large amount of chilled water directly flows back to the unit through the pressure difference bypass valve without effective utilization, resulting in significant energy waste.

[0037] In view of the above specific application scenarios, as the chilled water flow required by the terminal decreases, in order to effectively curb this trend of energy waste, according to the above Figure 2 As shown in the figure, 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 down to accurately match the system requirements, ensuring that while reducing the chilled water flow rate, the unnecessary bypass flow of the system is not increased, thereby reducing energy waste.

[0038] In order to accurately respond to this change, when the chilled water flow in the central air-conditioning chilled water system decreases, the set pressure difference value of the central air-conditioning chilled water system is dynamically adjusted according to the optimal working area of ​​the chilled water pump in the preset pressure difference change characteristic analysis diagram and the fuzzy PID control algorithm. Through this intelligent adjustment strategy, the set pressure difference value of the central air-conditioning chilled water system is no longer maintained at a fixed value, but is dynamically set to a changing range according to actual needs. It not only takes into account the safety and stability of the air-conditioning system, but also obtains efficient energy-saving benefits, realizing energy conservation and system optimization operation.

[0039] In some embodiments, step S102 includes: Determine whether the current time point is the end time point of the current cycle. If so, the adjusted set pressure difference value is used as the set pressure difference value corresponding to the next cycle. If not, the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the current cycle. If a new set pressure difference value is obtained, the new set pressure difference value is used as the adjusted set pressure difference value. If no new set pressure difference value is obtained, the set pressure difference value corresponding to the current cycle is used as the adjusted set pressure difference value.

[0040] In this embodiment, the set pressure difference value is periodically adjusted by automatically calculating the end time point of the cycle. The user only needs to input the preset set pressure difference value, and the subsequent calculation and adjustment processes are fully adapted to be automatically carried out without human intervention, which is highly automated and practical.

[0041] Please refer to Figure 3 , Figure 3 The present invention is a flowchart of the first step of step S102 in the central air-conditioning chilled water system control method.

[0042] In some embodiments, step S102 includes: S201. Acquire real-time information of a central air-conditioning chilled water system, where the real-time information includes a difference in indoor temperature of each room in a service area of ​​the central air-conditioning chilled water system.

[0043] S202: When the current time point is the end time point of the current cycle, a first temperature difference value is determined based on the indoor temperature difference value and used as measurement information, wherein the first temperature difference value is a temperature difference value of a target sub-area in the service area.

[0044] S203: When the first temperature difference is greater than the first preset lower limit, the real-time information and the measurement information are deleted, and the set pressure difference of the central air-conditioning chilled water system is used as the set pressure difference corresponding to the next cycle.

[0045] In some embodiments, the indoor temperature difference is equal to the difference between the actual temperature in the room and the set temperature.

[0046] Please refer to Figure 4 , Figure 4 The present invention is a flow chart of the second step of step S102 in the central air-conditioning chilled water system control method.

[0047] In some embodiments, step S102 includes: S301. When the first temperature difference is less than or equal to the first preset lower limit, based on the indoor temperature difference, determine the second temperature difference as measurement information, wherein the second temperature difference is the average temperature difference of the service area.

[0048] S302: When the second temperature difference is greater than the second preset lower limit, the real-time information and the measurement information are deleted, and the set pressure difference of the central air-conditioning chilled water system is used as the set pressure difference corresponding to the next cycle.

[0049] In some embodiments, when determining the second temperature difference value, the indoor temperature difference value of each room is obtained, and the average temperature difference value of the service area is calculated based on the preset coefficient of each room; when determining the first temperature difference value, the temperature difference value of the target sub-area is calculated based on the weight ratio between the target sub-area and the service area.

[0050] Please refer to Figure 5 , Figure 5 The present invention is a flowchart of the third step of step S102 in the central air-conditioning chilled water system control method.

[0051] In some embodiments, step S102 includes: S401. Obtain the supply and return water temperature difference of each terminal device in the central air-conditioning chilled water system and use it as real-time information.

[0052] S402. When the second temperature difference is less than or equal to the second preset lower limit, a third temperature difference is determined based on the supply and return water temperature difference and used as measurement information, wherein the third temperature difference is the supply and return water temperature difference of the target terminal device in the central air-conditioning chilled water system.

[0053] S403: When the third temperature difference value is not within the first preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0054] Please refer to Figure 6 , Figure 6 The present invention is a flowchart of the fourth step of step S102 in the central air-conditioning chilled water system control method.

[0055] In some embodiments, step S102 includes: S501. When the third temperature difference is within the first preset value range, a fourth temperature difference is determined based on the indoor temperature difference and used as measurement information, wherein the fourth temperature difference is an average temperature difference of each terminal device in the central air-conditioning chilled water system.

[0056] S502: When the fourth temperature difference value is not within the second preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

[0057] In some embodiments, when determining the third temperature difference value, the supply and return water temperature difference value of each terminal device in the central air-conditioning chilled water system is obtained, and the average temperature difference value of each terminal device in the central air-conditioning chilled water system is calculated based on the preset coefficient of each room; when determining the fourth temperature difference value, the supply and return water temperature difference value of the target terminal device is calculated based on the weight ratio between the target sub-area and the service area.

[0058] Please refer to Figure 7 , Figure 7 The fifth step flow chart of step S102 in the central air-conditioning chilled water system control method is shown.

[0059] In some embodiments, step S102 includes: 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] If the communication is abnormal, the current set pressure difference value DPn is cleared and the set pressure difference value of the system is restored to DPs to ensure the normal operation of the chilled water pump when the communication with the system platform is offline.

[0067] In an embodiment of a central air-conditioning chilled water system control method used in an actual scenario, first, according to factors such as the enclosure structure load, terminal equipment load, and changes in the number of people in each room, the cooling / heating weight coefficient Ki of each room is configured, and 1-5 rooms are selected in the service area and the sub-area where these rooms are located is set as the most unfavorable point area, that is, the target sub-area. The weight ratio is configured for the most unfavorable point area, and the minimum set temperature difference lower limit ΔTrzmin and the supply and return water temperature difference setting value ΔTdzset of the most unfavorable point area are configured. The comprehensive minimum set temperature difference lower limit ΔTrpmin and the supply and return water temperature difference setting value ΔTdpset are configured for all rooms in the service area.

[0068] Then, start the central air conditioning chilled water system, set the pressure difference of the chilled water main to the preset set pressure difference DPs, set the minimum operating frequency Fmin of the chilled water pump, set the room temperature alarm record Wri, the terminal equipment supply and return water alarm record Wdi and the chilled water pump alarm record WFi.

[0069] After the system operates normally, the indoor temperature Tr and the set temperature Ts of each room in the service area are collected in real time, and the difference between the two is calculated as the indoor temperature difference ΔTri. When ΔTri is not within the first alarm value range, a first alarm record Wri is generated; and the indoor temperature difference ΔTri of each room and the first alarm record Wri are uploaded and saved through the standard communication bus and standard communication protocol.

[0070] The supply and return water temperature difference ΔTdi of each terminal device in the central air-conditioning chilled water system is collected in real time. When ΔTdi is not within the second alarm value range, a second alarm record Wdi is generated, and the supply and return water temperature difference ΔTdi and the second alarm record Wdi are uploaded and saved through the standard communication bus and standard communication protocol.

[0071] The operating frequency Fi of the chilled water pump is collected in real time. When Fi is not within the third alarm value range, a third alarm record WFi is generated. The operating frequency Fi and the third alarm record WFi are uploaded and saved through the standard communication bus and standard communication protocol.

[0072] The indoor temperature difference ΔTri of each room is summarized, and the comprehensive regional weighted average ΔTrp is calculated as the average temperature difference of the service area according to the cooling / heating weight coefficient Ki of each room. According to the weight ratio of the most unfavorable point area, the set difference ΔTrz of the most unfavorable point is calculated as the temperature difference of the target sub-area.

[0073] The supply and return water temperature difference ΔTdi of each terminal device is summarized, and the comprehensive regional weighted average value ΔTdp is calculated according to the cooling / heating weight coefficient Ki of each room as the average temperature difference of each terminal device in the central air-conditioning chilled water system. According to the weight ratio of the most unfavorable point area, the supply and return water temperature difference ΔTdz of the most unfavorable point is calculated as the supply and return water temperature difference of the target terminal device.

[0074] Determine whether the end time of the cycle (10-30 minutes, this parameter is configurable) has been reached. If not, maintain the set pressure difference value corresponding to the current cycle.

[0075] If reached, first determine whether the most unfavorable point setting difference ΔTrz is less than or equal to the lower limit ΔTrzmin. If not, clear the various calculated values ​​​​calculated in 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 and waits for the next adjustment cycle.

[0076] If the setting difference ΔTrz at the most unfavorable point is less than or equal to the lower limit ΔTrzmin, then determine whether the weighted average setting difference ΔTrp of the comprehensive area is less than or equal to the lower limit ΔTrpmin. If so, clear the various calculated values ​​​​calculated in 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 and waits for the next adjustment cycle.

[0077] If the weighted average set difference ΔTrp of the comprehensive area is less than or equal to the lower limit ΔTrpmin, determine whether the supply and return water temperature difference ΔTdz at the most unfavorable point is within the range of the set value ΔTdzset (5℃±10%). If not, clear the various calculated values ​​​​calculated in the above steps and the above alarm records, and the chilled water pump will operate according to the set pressure difference value corresponding to the current cycle and wait for the next adjustment cycle.

[0078] If the supply and return water temperature difference ΔTdz at the most unfavorable point is within the range of the set value ΔTdzset, then determine whether the supply and return water temperature difference ΔTdp in the comprehensive area is within the range of the set value ΔTdpset (for example, 5℃±10%); if not, clear the various calculated values ​​​​and the above alarm records calculated in the above steps, and the chilled water pump will operate according to the set pressure difference value corresponding to the current cycle, waiting for the next adjustment cycle.

[0079] If it is determined whether the supply and return water temperature difference ΔTdp of the comprehensive area is within the set value ΔTdpset, the alarm records of each terminal device are detected. If any alarm record Wri, Wdi and WFi is detected, the calculated values ​​​​and the above alarm records calculated in the above steps are cleared, and the chilled water pump operates according to the set pressure difference value corresponding to the current cycle and waits for the next adjustment cycle.

[0080] If no alarm record is detected, a new set pressure difference value DPn=DPs+ΔP is calculated based on the optimal working area of ​​the chilled water pump in the preset pressure difference change characteristic analysis diagram and the fuzzy PID algorithm.

[0081] The new set pressure difference value DPn is sent to the controller of the chilled water pump, so that the chilled water pump in the constant pressure difference mode adjusts the operating frequency of the chilled water pump according to the new set pressure difference value until the next adjustment cycle.

[0082] refer to Fig. 9 , Fig. 9 The present invention is a structural schematic diagram of a central air-conditioning chilled water system control device.

[0083] In a second aspect, this embodiment provides a central air-conditioning chilled water system control device, the device comprising: The acquisition module 701 is used to acquire a set pressure difference value of a central air-conditioning chilled water system.

[0084] The adjustment module 702 is used to adjust the set pressure difference value within a preset period to obtain an adjusted set pressure difference value.

[0085] The control module 703 is used to control 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.

[0086] It will be appreciated by those skilled in the art that all or some of the steps and devices in the methods disclosed above may be implemented as software, firmware, hardware, and appropriate combinations thereof. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or implemented as hardware, or implemented as an integrated circuit, such as an application-specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or non-transitory medium) and a communication medium (or transient medium). As known to those skilled 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 include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. As is well known to those skilled in the art, communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0087] It can be understood that the contents of the above method embodiments are all applicable to the present device embodiments, the functions specifically implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0088] In a third aspect, an embodiment of the present application provides an electronic device, the electronic device comprising a memory and a processor, the memory storing a computer program, and the processor implementing any of the above central air conditioning chilled water system control methods when executing the computer program.

[0089] refer to Fig.10 , Fig.10 The hardware structure of an electronic device of another embodiment is illustrated, and the electronic device includes: The processor 801 may be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application; The memory 802 can 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). The memory 802 can store operating devices and other applications. When the technical solution provided in the embodiment of this specification is implemented by software or firmware, the relevant program code is stored in the memory 802, and the processor 801 calls and executes the central air-conditioning chilled water system control method of the embodiment of this application; Input / output interface 803, used to implement information input and output; The communication interface 804 is used to realize the communication interaction between the device and other devices. The communication can be realized through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.); A bus 805 that transmits information between various components of the device (e.g., the processor 801, the memory 802, the input / output interface 803, and the communication interface 804); The processor 801 , the memory 802 , the input / output interface 803 and the communication interface 804 are connected to each other in communication within the device via a bus 805 .

[0090] It can be understood that the contents of the above method embodiments are all applicable to the electronic device embodiment, the functions specifically implemented by the electronic device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0091] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a program executable by a processor, and the program executable by the processor is used to implement the central air-conditioning chilled water system control method as described in any one of the above specific embodiments when executed by the processor.

[0092] An embodiment of the present application also discloses a computer program product, including a computer program or computer instructions, wherein the computer program or computer instructions are stored in a computer-readable storage medium, a processor of a 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 as described in any of the previous embodiments.

[0093] It can be understood that the contents of the above method embodiments are all applicable to the present storage medium embodiments, the functions specifically implemented by the present storage medium embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0094] The above embodiment does not require any modification to the hardware of the refrigeration unit, and can be realized by only collecting and sending the pressure difference value through the platform software system. This greatly reduces the implementation cost and can quickly generate energy-saving economic benefits, which has significant advantages in the transformation and upgrading of central air-conditioning systems.

[0095] 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 are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, device, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are 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.

[0096] In the several embodiments provided in the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as 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 mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0097] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0098] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0099] If the 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 this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, referred to as ROM), random access memory (Random Access Memory, referred to as RAM), disk or optical disk and other media that can store program codes.

[0100] Although the description of the present application has been quite detailed and specifically describes several described embodiments, it is not intended to be limited to any of these details or embodiments or any particular embodiment, but should be regarded as providing a broad possible interpretation of these claims by reference to the attached claims, taking into account the prior art, so as to effectively cover the intended scope of the present application. In addition, the above description of the present application is based on the embodiments foreseeable by the inventor, and its purpose is to provide a useful description, and those non-substantial changes to the present application that have not yet been foreseen may still represent equivalent changes to the present application.

Claims

1. A central air conditioning chilled water system control method, characterized in that: The method comprises: Get the set pressure difference value of the central air-conditioning chilled water system; Within a preset period, adjusting the set pressure difference value to obtain an adjusted set pressure difference value; Based on the adjusted set pressure difference value, the chilled water pump of the central air-conditioning chilled water system is controlled to adjust the chilled water flow of the central air-conditioning chilled water system.

2. A central air-conditioning chilled water system control method according to claim 1, characterized in that: The method comprises: When it is detected that the communication is abnormal, 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.

3. A central air-conditioning chilled water system control method according to claim 1, characterized in that: The method comprises: When the set pressure difference value is adjusted, the target set pressure difference value is determined and used 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 pipeline resistance characteristic curve and the variable given pressure difference characteristic curve.

4. A central air-conditioning chilled water system control method according to claim 1, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Determine 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, the new set pressure difference value is used as the adjusted set pressure difference value; if no new set pressure difference value is obtained, the set pressure difference value corresponding to the current cycle is used as the adjusted set pressure difference value.

5. A central air-conditioning chilled water system control method according to any one of claims 1 to 4, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Acquire real-time information of the central air-conditioning chilled water system, wherein the real-time information includes the indoor temperature difference of each room in the service area of ​​the central air-conditioning chilled water system; When the current time point is the end time point of the current cycle, based on the indoor temperature difference, a first temperature difference value is determined as the measurement information, wherein the first temperature difference value is a temperature difference value of a target sub-area in the service area; When the first temperature difference value is greater than a first preset lower limit value, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

6. A central air-conditioning chilled water system control method according to claim 5, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: When the first temperature difference is less than or equal to the first preset lower limit, a second temperature difference is determined based on the indoor temperature difference and used as the measurement information, wherein the second temperature difference is an average temperature difference of the service area; When the second temperature difference value is greater than a second preset lower limit value, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

7. A central air-conditioning chilled water system control method according to claim 6, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Obtaining the supply and return water temperature difference of each terminal device in the central air-conditioning chilled water system as the real-time information; When the second temperature difference is less than or equal to the second preset lower limit, a third temperature difference is determined based on the supply and return water temperature difference and used as the measurement information, wherein the third temperature difference is the supply and return water temperature difference of the target terminal device in the central air-conditioning chilled water system; When the third temperature difference value is not within the first preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

8. A central air-conditioning chilled water system control method according to claim 7, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: When the third temperature difference is within the first preset value range, a fourth temperature difference is determined based on the indoor temperature difference and used as the measurement information, wherein the fourth temperature difference is an average temperature difference of each terminal device in the central air-conditioning chilled water system; When the fourth temperature difference value is not within the second preset value range, the real-time information and the measurement information are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle.

9. A central air-conditioning chilled water system control method according to claim 8, characterized in that: The step of adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value includes: Detecting alarm records, wherein when the first temperature difference value is not within a first alarm value range, a first alarm record is generated, when the second temperature difference value is not within a second alarm value range, a second alarm record is generated, and when it is detected that the frequency value of the chilled water pump is not within a third alarm value range, a third alarm record is generated; 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 measurement information, the real-time information and each of the alarm records are deleted, and the set pressure difference value of the central air-conditioning chilled water system is used as the set pressure difference value corresponding to the next cycle; 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.

10. A central air-conditioning chilled water system control device, characterized in that: The device comprises: An acquisition module is used to obtain a set pressure difference value of a central air-conditioning chilled water system; An adjusting module, used for adjusting the set pressure difference value within a preset period to obtain an adjusted set pressure difference value; The control module is used to control 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.

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

12. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the central air-conditioning chilled water system control method according to any one of claims 1 to 9 is implemented.

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