Method and system for controlling refrigeration outlet water temperature of air conditioner

Abstract

The invention discloses an air conditioner refrigeration outlet water temperature control method and system, and the method comprises the steps that for a plurality of room types, calculation data of all air conditioner rooms corresponding to the room types are obtained; for the multiple air-conditioned rooms, PMV values of the air-conditioned rooms are calculated according to the calculation data of the air-conditioned rooms; according to the preset weight corresponding to each room type and the PMV values of all the air-conditioning rooms, the overall PMV value is calculated; and on the basis of the overall PMV value, the air conditioner chilled water outlet temperature is calculated, the air conditioner chilled water outlet temperature is sent to control equipment, so that the control equipment controls the air conditioner refrigeration outlet water temperature of each air conditioner room according to the air conditioner chilled water outlet temperature and constraint conditions, and the constraint conditions are obtained through construction according to a function relation in advance. According to the control strategy based on the PMV value and weight calculation, high-precision and high-efficiency regulation and control can be provided for the air conditioner, and the high adaptability and the energy-saving effect are achieved.

Description

Technical Field

[0001] The present application relates to the field of air-conditioning energy-saving technology, and in particular to a method and system for controlling the outlet temperature of air-conditioning refrigeration water. Background Art

[0002] In the air conditioning cooling system, the water-cooled air conditioning system occupies an important share of the air conditioning market due to its advantages such as low price, low noise and high comfort. This system uses water as the heat exchange medium and undertakes the task of heat transfer between the end user and the air conditioning host. However, as the outlet temperature of the chilled water increases, the efficiency of the refrigeration unit increases, while the cooling performance of the terminal fan coil unit decreases, so the cooling effect will deteriorate, affecting the user's comfort. Therefore, how to control the outlet temperature of the air conditioning chilled water on the basis of meeting the user's comfort requirements is a problem that needs to be solved urgently.

[0003] In the existing technology, the control of the air-conditioning chilled water outlet temperature is generally for the purpose of energy saving. Generally, the air-conditioning chilled water outlet temperature is controlled according to the indoor and outdoor temperature, heat (enthalpy value) or the load rate of the chiller. However, there are many deficiencies when dealing with complex environments and system status changes, resulting in the inability to provide high-precision and high-efficiency air-conditioning chilled water outlet temperature regulation. Summary of the invention

[0004] Based on the above-mentioned deficiencies of the prior art, the present application provides a method and system for controlling the outlet water temperature of an air conditioner refrigeration system to solve the problem of being unable to provide high-precision and high-efficiency regulation.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] The first aspect of the present application provides a method for controlling the outlet temperature of air conditioning refrigeration water, comprising:

[0007] For each of the multiple room types, obtain calculation data of all air-conditioned rooms corresponding to the room type;

[0008] Calculating the PMV values ​​of the air-conditioned rooms respectively according to the calculation data of the air-conditioned rooms;

[0009] Calculate the overall PMV value according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms;

[0010] Based on the overall PMV value, the air-conditioning chilled water outlet temperature is calculated, and the air-conditioning chilled water outlet temperature is sent to the control device, so that the control device controls the air-conditioning refrigeration outlet temperature of each air-conditioned room according to the air-conditioning chilled water outlet temperature and constraint conditions; wherein the constraint conditions are obtained by constructing according to a pre-constructed functional relationship.

[0011] Optionally, in the above-mentioned air conditioning refrigeration water outlet temperature control method, the PMV values ​​of the air-conditioned rooms are calculated for each of the plurality of air-conditioned rooms according to the calculation data of the air-conditioned rooms, including:

[0012] For each of the plurality of air-conditioned rooms, determining a clothing surface area coefficient according to clothing thermal resistance in the calculation data of the air-conditioned rooms;

[0013] Calculate the clothing surface temperature according to the clothing surface area coefficient and the human metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data;

[0014] Determining a convection heat transfer coefficient according to the clothing surface temperature and the air temperature;

[0015] Based on the wind speed, relative humidity, human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculation data, the PMV value of the air-conditioned room is calculated using a PMV calculation function.

[0016] Optionally, in the above-mentioned air-conditioning cooling water outlet temperature control method, the overall PMV value is calculated according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms, including:

[0017] Obtain the number of rooms corresponding to each of the room types and the weight corresponding to each of the air-conditioned rooms;

[0018] Calculate the overall weight based on the weight corresponding to each of the air-conditioned rooms, the number of rooms, and the preset weight corresponding to each of the room types;

[0019] The overall PMV value is calculated based on the overall weight and the PMV values ​​of all air-conditioned rooms.

[0020] Optionally, in the above-mentioned air conditioner refrigeration water outlet temperature control method, the air conditioner chilled water outlet temperature is calculated based on the overall PMV value, including:

[0021] Obtain the inverse relationship between the PMV value and the target air conditioning chilled water outlet temperature;

[0022] According to the inverse relationship, construct a functional relationship between the PMV value and the target air-conditioning chilled water outlet temperature;

[0023] According to the overall PMV value, the air-conditioning chilled water outlet temperature is calculated using the functional relationship.

[0024] Optionally, in the above-mentioned air conditioner refrigeration water outlet temperature control method, after sending the air conditioner chilled water outlet temperature to the control device, it also includes:

[0025] Get the custom delay time;

[0026] Determine whether the delay time is greater than a preset threshold;

[0027] If the delay time is greater than the preset threshold, return to execute the step of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively;

[0028] If the delay time is not greater than the preset threshold, the process periodically returns to execute the process of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively.

[0029] A second aspect of the present application provides a control system for air conditioning refrigeration water outlet temperature, comprising:

[0030] A data acquisition unit, used for acquiring, for each of a plurality of room types, calculation data of all air-conditioned rooms corresponding to the room type;

[0031] A first calculation unit, configured to calculate the PMV values ​​of the air-conditioned rooms according to the calculation data of the air-conditioned rooms respectively for the plurality of air-conditioned rooms;

[0032] A second calculation unit, used to calculate the overall PMV value according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms;

[0033] The third calculation unit is used to calculate the air-conditioning chilled water outlet temperature based on the overall PMV value, and send the air-conditioning chilled water outlet temperature to the control device, so that the control device controls the air-conditioning refrigeration outlet temperature of each air-conditioned room according to the air-conditioning chilled water outlet temperature and constraint conditions; wherein the constraint conditions are constructed according to a pre-constructed functional relationship.

[0034] Optionally, in the above-mentioned air-conditioning refrigeration water outlet temperature control system, the first calculation unit includes:

[0035] A first determining unit is used to determine the clothing surface area coefficient for each of the plurality of air-conditioned rooms according to the clothing thermal resistance in the calculation data of the air-conditioned rooms;

[0036] a fourth calculation unit, for calculating the surface temperature of the clothing according to the clothing surface area coefficient and the human metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data;

[0037] A second determining unit, configured to determine a convection heat transfer coefficient according to the clothing surface temperature and the air temperature;

[0038] The fifth calculation unit is used to calculate the PMV value of the air-conditioned room using a PMV calculation function based on the wind speed, relative humidity, human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculation data.

[0039] Optionally, in the above-mentioned air-conditioning refrigeration water outlet temperature control system, the second calculation unit includes:

[0040] An acquisition unit, used to acquire the number of rooms corresponding to each of the room types and the weight corresponding to each of the air-conditioned rooms;

[0041] A sixth calculation unit, configured to calculate an overall weight based on a weight corresponding to each of the air-conditioned rooms, the number of rooms, and a preset weight corresponding to each of the room types;

[0042] The seventh calculation unit is used to calculate the overall PMV value according to the overall weight and the PMV values ​​of all air-conditioned rooms.

[0043] Optionally, in the above-mentioned air conditioning refrigeration water outlet temperature control system, the third calculation unit includes:

[0044] A relationship acquisition unit, used to acquire an inverse relationship between the PMV value and a target air-conditioning chilled water outlet temperature;

[0045] A construction unit, configured to construct a functional relationship between the PMV value and a target air-conditioning chilled water outlet temperature according to the inverse relationship;

[0046] An eighth calculation unit is used to calculate the air-conditioning chilled water outlet temperature according to the overall PMV value using the functional relationship.

[0047] Optionally, the above-mentioned air conditioning refrigeration water outlet temperature control system further includes:

[0048] A time acquisition unit is used to obtain a custom delay time;

[0049] A judging unit, used to judge whether the delay time is greater than a preset threshold;

[0050] A first execution unit, configured to return to execute the step of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively if the delay time is greater than a preset threshold;

[0051] The second execution unit is configured to periodically return to execute the step of acquiring the calculation data of all air-conditioned rooms corresponding to each room type if the delay time is not greater than a preset threshold.

[0052] The present application provides a method for controlling the outlet temperature of air-conditioning refrigeration water. First, for multiple room types, the calculation data of all air-conditioning rooms corresponding to the room type are obtained. Secondly, for multiple air-conditioning rooms, the PMV value of the air-conditioning room is calculated according to the calculation data of the air-conditioning room. Then, according to the preset weight corresponding to each room type and the PMV value of all air-conditioning rooms, the overall PMV value is calculated. Finally, based on the overall PMV value, the outlet temperature of the air-conditioning chilled water is calculated, and the outlet temperature of the air-conditioning chilled water is sent to the control device, so that the control device controls the outlet temperature of the air-conditioning refrigeration water of each air-conditioning room according to the outlet temperature of the air-conditioning chilled water and the constraint condition, wherein the constraint condition is constructed in advance according to the functional relationship. Therefore, the control strategy based on the PMV value and weight calculation can provide high-precision and high-efficiency regulation for the air-conditioning, and can make the air-conditioning system more efficient and comfortable, while having strong adaptability and energy-saving effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0054] Figure 1 A flow chart of a method for controlling the outlet water temperature of an air conditioner provided in an embodiment of the present application;

[0055] Figure 2 A flowchart of a method for calculating PMV provided in another embodiment of the present application;

[0056] Figure 3 A flowchart of a method for calculating an overall PMV is provided for another embodiment of the present application;

[0057] Figure 4 A flow chart of a method for calculating the outlet temperature of chilled water of an air conditioner provided in another embodiment of the present application;

[0058] Figure 5 A schematic diagram of a linear function structure provided in an embodiment of the present application;

[0059] Figure 6 A schematic structural diagram of a control system for air conditioning refrigeration water outlet temperature provided in another embodiment of the present application. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0061] In this application, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0062] The present application provides a method for controlling the outlet temperature of air conditioning refrigeration water. Figure 1 As shown, the specific steps include:

[0063] S101. For each of multiple room types, obtain calculation data of all air-conditioned rooms corresponding to the room type.

[0064] It is understandable that in order to meet the requirements of air conditioning control for different room types, it is necessary to obtain the calculation data of all air-conditioned rooms corresponding to multiple room types, so that the PMV value can be calculated based on the calculation data later. Then, as the PMV value changes, the air-conditioning chilled water outlet temperature value can be dynamically set to achieve the purpose of energy saving while ensuring user comfort.

[0065] For example, the room type may include a merchandise store type, a discussion room type, etc., and all air-conditioned rooms corresponding to the room type refer to all air-conditioned rooms in a room. Calculation data refers to data that can be used to calculate the PMV value.

[0066] S102, calculating the PMV values ​​of the air-conditioned rooms respectively according to the calculation data of the air-conditioned rooms.

[0067] Specifically, PMV (Predicted Mean Vote) is an index used to measure the thermal comfort of people in an air-conditioned room under a specific environment. Therefore, the PMV value of the air-conditioned room is calculated based on the obtained calculation data of the air-conditioned room, where the calculation data may include air temperature, humidity, etc. required to calculate the PMV value.

[0068] Optionally, in another embodiment of the present application, a specific implementation of step S102 is as follows: Figure 2 As shown, the following steps are included:

[0069] S201. Determine, for each of a plurality of air-conditioned rooms, clothing surface area coefficients according to clothing thermal resistance in calculation data of the air-conditioned rooms.

[0070] Specifically, the clothing surface coefficient f cl The formula for determining is:

[0071]

[0072] Among them, I cl is the thermal resistance of clothing, in units of square meters Kelvin per watt (m2·K / W), obtained through calculation and conversion by a calculation program. cl The clothing surface area coefficient is I cl Function of the thermal resistance of the garment.

[0073] S202, calculating the clothing surface temperature according to the clothing surface area coefficient and the human metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data.

[0074] Specifically, the clothing surface temperature t cl The calculation formula is:

[0075]

[0076] Where M is the metabolic rate of the human body, W is the effective mechanical power (usually zero), I cl is the thermal resistance of clothing, is the mean radiation temperature, h c is the convective heat transfer coefficient, t a is the air temperature. It should be noted that the clothing surface temperature t is calculated by the calculation program using the calculation data. cl .t cl The surface temperature of the clothing is I cl Function of the thermal resistance of the garment.

[0077] S203: Determine the convection heat transfer coefficient according to the clothing surface temperature and the air temperature.

[0078] Specifically, the convective heat transfer coefficient h c The formula for determining is:

[0079]

[0080] Among them, t cl is the clothing surface temperature, t a is the air temperature, v ar is the relative wind speed. c is the convective heat transfer coefficient, is the wind speed v a function.

[0081] S204. Based on the wind speed, relative humidity, human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculated data, the PMV value of the air-conditioned room is calculated using a PMV calculation function.

[0082] Specifically, the calculation formula of PMV value is:

[0083]

[0084] Among them, P a is the partial pressure of water vapor, which can be calculated from the air temperature and relative humidity, M is the metabolic rate of the human body, W is the effective mechanical power (usually zero), I cl is the thermal resistance of clothing, is the mean radiation temperature, h c is the convective heat transfer coefficient, t a is the air temperature, and the above parameters are all indoor parameters.

[0085] S103: Calculate the overall PMV value according to the preset weight corresponding to each room type and the PMV values ​​of all air-conditioned rooms.

[0086] It should be noted that the weight corresponding to each room type is different, so the impact on the overall PMV will also be different. For example, the comfort level of some larger rooms or frequently used rooms has a greater impact on the overall PMV. Therefore, it is necessary to first determine the preset weight corresponding to each room type, which can be set according to the room area, frequency of use, number of people or other relevant factors, and then calculate the overall PMV value through the weighted average method based on the preset weight corresponding to each room type and the PMV values ​​of all air-conditioned rooms.

[0087] Optionally, in another embodiment of the present application, a specific implementation of step S103 is as follows: Figure 3 As shown, the following steps are included:

[0088] S301. Obtain the number of rooms corresponding to each room type and the weight corresponding to each air-conditioned room.

[0089] Specifically, in order to reasonably evaluate and optimize the energy efficiency and comfort of the air-conditioning system in a building or facility and formulate a more accurate air-conditioning control strategy, it is necessary to obtain in advance the number of rooms corresponding to each room type and the weight corresponding to each air-conditioned room.

[0090] S302: Calculate the overall weight based on the weight corresponding to each air-conditioned room, the number of rooms, and the preset weight corresponding to each room type.

[0091] Specifically, the calculation formula of the overall weight is:

[0092]

[0093] Where n is the number of rooms, α i is the thermal comfort weight of the i-th room.

[0094] S303: Calculate the overall PMV value according to the overall weight and the PMV values ​​of all air-conditioned rooms.

[0095] Specifically, the calculation formula for the overall PMV value is:

[0096]

[0097] in, is the overall weight, n is the number of rooms, α i is the thermal comfort weight of the i-th room, PMV i is the PMV value of the i-th room.

[0098] S104. Calculate the air-conditioning chilled water outlet temperature based on the overall PMV value, and send the air-conditioning chilled water outlet temperature to the control device, so that the control device controls the air-conditioning refrigeration outlet temperature of each air-conditioned room according to the air-conditioning chilled water outlet temperature and the constraint condition.

[0099] It should be noted that in the embodiment of the present application, the air-conditioning chilled water outlet temperature is calculated based on the overall PMV value by the thermal comfort model PMV. Once the chilled water outlet temperature required for each air-conditioned room is calculated, the control system will receive the temperature value. Based on this, the control device will start the following control strategy:

[0100] Monitor the actual PMV value of the room: Use the temperature and humidity sensors in the room to monitor the changes in the PMV value in real time.

[0101] Adjust the chilled water temperature: Based on the real-time monitoring data, the control device automatically adjusts the chilled water outlet temperature to keep the PMV value in the room as close to the target value as possible.

[0102] Consider constraints: such as the maximum chilled water temperature of the air-conditioning system, energy efficiency requirements, air-conditioning load and other constraints to ensure that the control process is carried out under the constraints.

[0103] The control device will control the chilled water temperature of each air-conditioned room based on the above calculation results. The control strategy may include:

[0104] PID control (proportional-integral-derivative control): real-time adjustment of chilled water temperature to reduce PMV error.

[0105] Fuzzy control: When the system complexity is high or the environment changes greatly, fuzzy control can provide more flexible adjustment.

[0106] Multi-loop control: If there are multiple air-conditioned rooms, each room may have different chilled water temperature requirements. The control system can adopt a distributed control strategy to adjust it room by room.

[0107] The constraint conditions are constructed based on pre-constructed functional relationships.

[0108] Specifically, the purpose of setting the upper and lower limits of the temperature is: Usually the chilled water outlet temperature ranges from 7 to 12°C. Below 7 degrees, the chiller may work abnormally, mainly to protect the chiller equipment. Above 12 degrees, the cooling effect will become very poor, and the meaning of starting the machine is lost. Therefore, the purpose of setting the upper and lower limits is to ensure that the chiller works under safe and stable conditions. The purpose of setting the upper and lower limits of PMV is: the meaning of the PMV calculation result is +3 hot, +2 warm, +1 slightly warm, 0 moderate, -1 slightly cool, -2 cool, -3 cold. The purpose of setting the upper and lower limits is to select appropriate upper and lower limit values ​​to avoid the problem of people feeling hot and cold, and to ensure a certain degree of comfort, which is the purpose of the constraints.

[0109] Specifically, the constraints are: 下限 ≤T≤t 上限 , PMV 舒适度下限 ≤PMV 整体 ≤PMV 舒适度上限 .

[0110] in:

[0111] t 下限 The lower limit of the outlet temperature of the air-conditioning chilled water, in degrees Celsius (℃), t 上限 The upper limit of the outlet temperature of the air-conditioning chilled water, in degrees Celsius (℃), PMV 舒适度下限 PMV is the lower limit of the thermal comfort level of the human body. Below this lower limit, the body feels cold. 舒适度上限It is the upper limit of the thermal comfort level of the human body. If the temperature is higher than this limit, the body will feel hotter. For rooms with higher comfort requirements, the upper and lower limits are smaller to maintain a certain degree of comfort. For rooms with lower comfort requirements, the upper and lower limits can be set larger.

[0112] Control equipment generally refers to chillers. For example, the actual value of the outlet water temperature is 7 degrees, and the set value is also 7 degrees. When the set value changes to 8 degrees, the controller changes the outlet water temperature by adjusting the compressor load, so that the actual value of the outlet water temperature rises by 8 degrees (it takes a certain amount of time, not instantaneous).

[0113] Optionally, in another embodiment of the present application, a specific implementation method of calculating the outlet temperature of the air-conditioning chilled water based on the overall PMV value in step S104 is as follows: Figure 4 As shown, the following steps are included:

[0114] S401. Obtain an inverse relationship between the PMV value and the target air-conditioning chilled water outlet temperature.

[0115] It is understandable that in air conditioning refrigeration systems, when PMV 整体 In PMV 舒适度下限 When the corresponding air conditioning chilled water outlet temperature T value should be t 上限 , if PMV 整体 Gradually increase, the T value can be appropriately reduced to ensure user comfort. Similarly, when PMV 整体 In PMV 舒适度上限 When the corresponding air conditioning chilled water outlet temperature T value should be t 下限 At this time, if the overall PMV value gradually decreases, the T value can be appropriately increased to save energy. Therefore, it can be obtained that the relationship between the PMV value and the target air-conditioning chilled water outlet temperature is inversely proportional.

[0116] S402: construct a functional relationship between the PMV value and the target air-conditioning chilled water outlet temperature based on the inverse relationship.

[0117] Specifically, through the inverse relationship, the functional relationship between the PMV value and the target air conditioning chilled water outlet temperature is constructed as a monotonically decreasing function, that is, T=f(PMV 整体 ).

[0118] S403. Calculate the air-conditioning chilled water outlet temperature using a functional relationship according to the overall PMV value.

[0119] Specifically, substitute the overall PMV value into the functional relationship T = f(PMV 整体 ) to obtain the air conditioning chilled water outlet temperature.

[0120] Optionally, after the air conditioner chilled water outlet temperature is sent to the control device, that is, after executing step S104, the frequency of calculating the air conditioner chilled water outlet temperature can also be controlled to reduce the calculation burden, improve the operating efficiency of the system, avoid excessive reaction or oscillation of the system, maintain the stability of the system, save energy and improve efficiency, and reduce unnecessary energy consumption. Therefore, another embodiment of the present application provides a method for calculating the frequency, comprising the following steps:

[0121] Get the custom delay time.

[0122] Optionally, the delay time ranges from 5 to 60 minutes, and of course may be other time thresholds, which can be specifically set according to requirements.

[0123] Determine whether the delay time is greater than a preset threshold.

[0124] It should be noted that if the air conditioning is too intensively controlled, the temperature will not be stable, which is not conducive to the safe operation of the equipment and system. Therefore, it can be controlled by setting the delay time, that is, judging whether the delay time is greater than the preset threshold. If the delay time is greater than the preset threshold, it is necessary to calculate the chilled water outlet temperature setting value T (°C) in real time, so it is necessary to return to step S101 immediately. If the delay time is not greater than the preset threshold, the chilled water outlet temperature setting value T (°C) can be calculated at intervals of the corresponding time, that is, periodically return to step S101.

[0125] For ease of understanding, the control process of the air conditioning refrigeration outlet water temperature of the present application can be described below using a specific application scenario. This application scenario takes a large project in Beijing as an example to illustrate the implementation method of the present control method in an actual project.

[0126] The control method is built into the integrated energy management and control platform. The received telesignal and telemetry values ​​are transmitted to the industrial gateway through the field equipment control cabinet by wired means, and then transmitted to the integrated energy management and control platform by the industrial gateway by wired or wireless means. After analysis and calculation by the integrated energy management and control platform, the control command is sent to the PLC or DCC control cabinet for control, or it can be directly sent to the local equipment for control.

[0127] This application scenario uses the following formula to calculate the PMV value of each room in the commercial complex:

[0128]

[0129]

[0130]

[0131]

[0132] The method of obtaining or setting parameters in the formula is:

[0133] t a Air temperature: obtained through the room indoor temperature and humidity sensor, in degrees Celsius (℃).

[0134] RH air relative humidity: obtained through the room indoor temperature and humidity sensor, the unit is percentage (%).

[0135] Mean radiant temperature: equal to the air temperature, expressed in degrees Celsius (℃).

[0136] v a Wind speed: Considering the indoor scene of the commercial complex, combined with the provisions of the national standard "GB / T 28591-2012 Wind Force Level", set v a The wind speed is 0.1m / s.

[0137] M human metabolic rate: Taking into account the sales and shopping scenarios of commercial complexes, combined with the provisions of the national standard "GB / T 18049-2017 Ergonomics of thermal environments - Analysis, measurement and interpretation of thermal comfort by calculating PMV and PPD indices and local thermal comfort criteria", the M human metabolic rate is set to 1.4met.

[0138] I cl Clothing thermal resistance: Considering the comprehensive clothing of people in the air-conditioning and cooling season, combined with the provisions of the national standard "GB / T 18049-2017 Ergonomics of thermal environment - Analysis, measurement and interpretation of thermal comfort by calculating PMV and PPD index and local thermal comfort criteria", I is set cl The thermal resistance of the clothing is 0.76clo. For other parameters, please refer to the description of the above embodiment.

[0139] The PMV value of each room is calculated using the above six data values ​​of each room.

[0140] There are 134 rooms in a certain independent cooling area of ​​the commercial complex, and the functional types are sales shops, catering shops and toilets. The PMV weight assignment of each room is shown in Table 1 below:

[0141] Room Types Sales Store Restaurants bathroom total Number of rooms (n) 119 11 4 134 Room Type Weight a b c 1 Weight of each room (αi) a / 119 b / 11 c / 4 /

[0142] From the above table, the overall PMV value of the commercial complex is calculated as follows:

[0143]

[0144] In this embodiment, the room function type is used as the basis for assigning weights to the PMV values, which is only an example of the requirements of this patent. Other methods of assigning weights to the PMV values ​​based on various room conditions are within the scope of protection of this patent.

[0145] The functional relationship between the air conditioning chilled water outlet temperature setting value T (℃) and the overall PMV value of the commercial complex is as follows: T = f (PMV 整体商业 ).

[0146] The constraints are as follows:

[0147] t 下限 ≤T≤t 上限

[0148] PMV 舒适度下限 ≤PMV 整体 ≤PMV 舒适度上限

[0149] Function T = f(PMV 整体商业 ) is a monotonically decreasing function.

[0150] The range of the set value T (°C) of the chilled water outlet temperature of the air conditioner in this embodiment is based on the national standard "GB / T 18430.1-2007 Vapor Compression Cycle Chiller (Heat Pump) Unit Part 1: Chiller (Heat Pump) Unit for Industrial or Commercial Use and Similar Purposes", and the values ​​are:

[0151] 5℃≤T≤15℃

[0152] The upper and lower limits of the overall PMV comfort level of the commercial complex in this embodiment are based on the national standard "GB / T 50785-2012 Standard for Evaluation of Indoor Thermal and Humid Environment of Civil Buildings", and the values ​​are:

[0153] -0.5≤PMV 整体商业 ≤+0.5

[0154] In this embodiment, the function T=f(PMV overall business) is selected as a linear function, from which the functional relationship can be obtained as follows (see Figure 5 ):

[0155] T = -10 × PMV 整体商业 +10

[0156] In this embodiment, the constraint selection method and the function selection type are only examples required by this patent. Other constraint selection methods and function selection types are within the protection scope of this patent.

[0157] According to PMV 整体商业 And the functional relationship: T = -10 × PMV 整体商业+10, calculate the air conditioning chilled water outlet temperature set value T (℃) and output it to the corresponding control device.

[0158] This control method calculates the frequency by setting the delay time:

[0159] In this embodiment, the delay time is selected as 5 minutes, that is, the air-conditioning chilled water outlet temperature setting value T (° C.) is calculated every 5 minutes.

[0160] When the delay is over, the control method returns to the first step and performs a loop calculation.

[0161] In this embodiment, the selection result of the delay time is only an example of the requirements of this patent, and the selection results of other delay times are within the protection scope of this patent.

[0162] The present application provides a method for controlling the outlet temperature of air-conditioning refrigeration water. First, for multiple room types, the calculation data of all air-conditioning rooms corresponding to the room type are obtained. Secondly, for multiple air-conditioning rooms, the PMV value of the air-conditioning room is calculated according to the calculation data of the air-conditioning room. Then, according to the preset weight corresponding to each room type and the PMV value of all air-conditioning rooms, the overall PMV value is calculated. Finally, based on the overall PMV value, the outlet temperature of the air-conditioning chilled water is calculated, and the outlet temperature of the air-conditioning chilled water is sent to the control device, so that the control device controls the outlet temperature of the air-conditioning refrigeration water of each air-conditioning room according to the outlet temperature of the air-conditioning chilled water and the constraint condition, wherein the constraint condition is constructed in advance according to the functional relationship. Therefore, the control strategy based on the PMV value and weight calculation can provide high-precision and high-efficiency regulation for the air-conditioning, and can make the air-conditioning system more efficient and comfortable, while having strong adaptability and energy-saving effects.

[0163] Another embodiment of the present application provides a control system for air conditioning refrigeration water outlet temperature, such as Figure 6 As shown, it includes the following units:

[0164] The data acquisition unit 601 is used to acquire the calculation data of all air-conditioned rooms corresponding to the room types for each of the multiple room types.

[0165] The first calculation unit 602 is used to calculate the PMV values ​​of the air-conditioned rooms according to the calculation data of the air-conditioned rooms respectively.

[0166] The second calculation unit 603 is used to calculate the overall PMV value according to the preset weight corresponding to each room type and the PMV values ​​of all air-conditioned rooms.

[0167] The third calculation unit 604 is used to calculate the air conditioner chilled water outlet temperature based on the overall PMV value, and send the air conditioner chilled water outlet temperature to the control device, so that the control device controls the air conditioner refrigeration water outlet temperature of each air-conditioned room according to the air conditioner chilled water outlet temperature and the constraint condition. The constraint condition is constructed according to a pre-constructed functional relationship.

[0168] It should be noted that the specific working process of the above modules in the embodiment of the present application can refer to steps S101 to S104 in the above method embodiment, which will not be repeated here.

[0169] Optionally, in another embodiment of the present application, in a control system for air conditioning refrigeration water outlet temperature, the first calculation unit 602 includes:

[0170] The first determination unit is used to determine the clothing surface area coefficient for each of the plurality of air-conditioned rooms according to the clothing thermal resistance in the calculation data of the air-conditioned rooms.

[0171] The fourth calculation unit is used to calculate the clothing surface temperature according to the clothing surface area coefficient and the human body metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data.

[0172] The second determining unit is used to determine the convection heat transfer coefficient according to the clothing surface temperature and the air temperature.

[0173] The fifth calculation unit is used to calculate the PMV value of the air-conditioned room using the PMV calculation function based on the wind speed, relative humidity and human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculated data.

[0174] Optionally, in another embodiment of the present application, in a control system for air conditioning refrigeration water outlet temperature, the second calculation unit 602 includes:

[0175] The acquisition unit is used to obtain the number of rooms corresponding to each room type and the weight corresponding to each air-conditioned room.

[0176] The sixth calculation unit is used to calculate the overall weight based on the weight corresponding to each air-conditioned room, the number of rooms and the preset weight corresponding to each room type.

[0177] The seventh calculation unit is used to calculate the overall PMV value according to the overall weight and the PMV values ​​of all air-conditioned rooms.

[0178] Optionally, in another embodiment of the present application, in a control system for air conditioning refrigeration water outlet temperature, the third calculation unit 603 includes:

[0179] The relationship acquisition unit is used to acquire the inverse relationship between the PMV value and the target air-conditioning chilled water outlet temperature.

[0180] The construction unit is used to construct a functional relationship between the PMV value and the target air-conditioning chilled water outlet temperature according to an inverse relationship.

[0181] The eighth calculation unit is used to calculate the air-conditioning chilled water outlet temperature according to the overall PMV value using a functional relationship.

[0182] Optionally, another embodiment of the present application provides an air conditioning refrigeration water outlet temperature control system, further comprising:

[0183] The time acquisition unit is used to obtain the custom delay time.

[0184] The judgment unit is used to judge whether the delay time is greater than a preset threshold.

[0185] The first execution unit is used to return to execute for each room type respectively, and obtain calculation data of all air-conditioned rooms corresponding to the room type if the delay time is greater than a preset threshold.

[0186] The second execution unit is used for periodically returning to execute for each room type respectively, if the delay time is not greater than a preset threshold, to obtain calculation data of all air-conditioned rooms corresponding to the room type.

[0187] It should be noted that the specific working process of each module provided in the above embodiments of the present application can refer to the corresponding steps in the above method embodiments, which will not be repeated here.

[0188] It should also be noted that the control system for air-conditioning refrigeration water outlet temperature provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiment of the present application will not be described in detail here.

[0189] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0190] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling the outlet water temperature of an air conditioner, characterized in that: include: For each of the multiple room types, obtain calculation data of all air-conditioned rooms corresponding to the room type; Calculating the PMV values ​​of the air-conditioned rooms respectively according to the calculation data of the air-conditioned rooms; Calculate the overall PMV value according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms; Based on the overall PMV value, the air-conditioning chilled water outlet temperature is calculated, and the air-conditioning chilled water outlet temperature is sent to the control device, so that the control device controls the air-conditioning refrigeration outlet temperature of each air-conditioned room according to the air-conditioning chilled water outlet temperature and constraint conditions; wherein the constraint conditions are obtained by constructing according to a pre-constructed functional relationship.

2. The method according to claim 1, characterized in that The step of calculating the PMV values ​​of the air-conditioned rooms respectively for the plurality of air-conditioned rooms according to the calculated data of the air-conditioned rooms comprises: For each of the plurality of air-conditioned rooms, determining a clothing surface area coefficient according to clothing thermal resistance in the calculation data of the air-conditioned rooms; Calculate the clothing surface temperature according to the clothing surface area coefficient and the human metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data; Determining a convection heat transfer coefficient according to the clothing surface temperature and the air temperature; Based on the wind speed, relative humidity, human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculation data, the PMV value of the air-conditioned room is calculated using a PMV calculation function.

3. The method according to claim 1, characterized in that The calculating of the overall PMV value according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms includes: Obtain the number of rooms corresponding to each of the room types and the weight corresponding to each of the air-conditioned rooms; Calculate the overall weight based on the weight corresponding to each of the air-conditioned rooms, the number of rooms, and the preset weight corresponding to each of the room types; The overall PMV value is calculated based on the overall weight and the PMV values ​​of all air-conditioned rooms.

4. The method according to claim 1, characterized in that: The step of calculating the air conditioning chilled water outlet temperature based on the overall PMV value includes: Obtain the inverse relationship between the PMV value and the target air conditioning chilled water outlet temperature; According to the inverse relationship, construct a functional relationship between the PMV value and the target air-conditioning chilled water outlet temperature; According to the overall PMV value, the air-conditioning chilled water outlet temperature is calculated using the functional relationship.

5. The method according to claim 1, characterized in that After sending the air conditioner chilled water outlet temperature to the control device, the method further includes: Get the custom delay time; Determine whether the delay time is greater than a preset threshold; If the delay time is greater than the preset threshold, return to execute the step of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively; If the delay time is not greater than the preset threshold, the process periodically returns to execute the process of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively.

6. A control system for air conditioning refrigeration water outlet temperature, characterized in that: include: A data acquisition unit, used for acquiring, for each of a plurality of room types, calculation data of all air-conditioned rooms corresponding to the room type; A first calculation unit, configured to calculate the PMV values ​​of the air-conditioned rooms according to the calculation data of the air-conditioned rooms respectively for the plurality of air-conditioned rooms; A second calculation unit, used to calculate the overall PMV value according to the preset weight corresponding to each of the room types and the PMV values ​​of all air-conditioned rooms; The third calculation unit is used to calculate the air-conditioning chilled water outlet temperature based on the overall PMV value, and send the air-conditioning chilled water outlet temperature to the control device, so that the control device controls the air-conditioning refrigeration outlet temperature of each air-conditioned room according to the air-conditioning chilled water outlet temperature and constraint conditions; wherein the constraint conditions are constructed according to a pre-constructed functional relationship.

7. The system according to claim 6, characterized in that The first computing unit comprises: A first determining unit is used to determine the clothing surface area coefficient for each of the plurality of air-conditioned rooms according to the clothing thermal resistance in the calculation data of the air-conditioned rooms; a fourth calculation unit, for calculating the surface temperature of the clothing according to the clothing surface area coefficient and the human metabolic rate, effective mechanical power, clothing thermal resistance, average radiation temperature, convection heat transfer coefficient and air temperature in the calculation data; A second determining unit, configured to determine a convection heat transfer coefficient according to the clothing surface temperature and the air temperature; The fifth calculation unit is used to calculate the PMV value of the air-conditioned room using a PMV calculation function based on the wind speed, relative humidity, human metabolic rate, air temperature, average radiation temperature, clothing thermal resistance, clothing surface area coefficient, and clothing surface temperature in the calculation data.

8. The system according to claim 7, characterized in that The second computing unit comprises: An acquisition unit, used to acquire the number of rooms corresponding to each of the room types and the weight corresponding to each of the air-conditioned rooms; A sixth calculation unit, configured to calculate an overall weight based on a weight corresponding to each of the air-conditioned rooms, the number of rooms, and a preset weight corresponding to each of the room types; The seventh calculation unit is used to calculate the overall PMV value according to the overall weight and the PMV values ​​of all air-conditioned rooms.

9. The system according to claim 6, characterized in that The third computing unit comprises: A relationship acquisition unit, used to acquire an inverse relationship between the PMV value and a target air-conditioning chilled water outlet temperature; A construction unit, configured to construct a functional relationship between the PMV value and a target air-conditioning chilled water outlet temperature according to the inverse relationship; An eighth calculation unit is used to calculate the air-conditioning chilled water outlet temperature according to the overall PMV value using the functional relationship.

10. The system according to claim 6, characterized in that Also includes: A time acquisition unit is used to obtain a custom delay time; A judging unit, used to judge whether the delay time is greater than a preset threshold; A first execution unit, configured to return to execute the step of obtaining the calculation data of all air-conditioned rooms corresponding to each room type respectively if the delay time is greater than a preset threshold; The second execution unit is configured to periodically return to execute the step of acquiring the calculation data of all air-conditioned rooms corresponding to each room type if the delay time is not greater than a preset threshold.

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