Control method and system for central air conditioning unit

Abstract

The present application relates to the field of equipment control technology, and in particular to a control method and system for a central air-conditioning unit. The method includes: when the central air-conditioning unit cools a target space, determining the cooling capacity of the central air-conditioning unit for the target space in different time periods; determining an evaluation value of the cooling capacity of the central air-conditioning unit for the target space in the current time period; obtaining the initial cooling demand of the target space in the current time period, and determining the target cooling demand for the target space in the next time period of the current time period based on the initial cooling demand and the evaluation value corresponding to the current time period; and controlling the cooling of the target space by the central air-conditioning unit in the next time period based on the target cooling demand for the target space in the next time period. Through the above technical solution, the air outlet of the central air-conditioning unit can respond more quickly to changes in ambient temperature.

Description

Technical Field

[0001] The present application relates to the field of equipment control technology, and in particular to a control method and system for a central air-conditioning unit. Background Art

[0002] Central air conditioning units can be used in large buildings such as civil, commercial and industrial buildings. Central air conditioning units can cool the space to be refrigerated and maintain the temperature of the environment to be refrigerated within a pre-set temperature range.

[0003] For example, when a central air-conditioning unit is cooling, the chilled water circulation pump sends chilled water into the evaporator in the chiller. The refrigerant absorbs the heat of the chilled water in the evaporator, lowering the temperature of the chilled water. The cooled chilled water is transported to the chilled water coil in the air handling unit through a pipe. The indoor air is blown through the chilled water coil by the fan, and the heat in the air is transferred to the chilled water, causing the air to be cooled. The cooled air is blown into the environment to be cooled by the terminal fan, thereby cooling the space to be cooled.

[0004] In order to achieve control of central air conditioning, a Chinese patent application document with publication number CN117346307A provides a control method for a terminal fan of a central air conditioning, including: obtaining a first initial temperature value, a second initial temperature value, a set temperature and an initial energy conversion value detected by multiple sensors, the first initial temperature value and the second initial temperature value constitute a first temperature field; determining a working mode according to the first initial temperature value and the set temperature; obtaining a first current temperature value and a second current temperature value detected by multiple sensors after a preset time interval, the first current temperature value and the second current temperature value constitute a second temperature field; based on the working mode, calculating the first initial temperature value, the second initial temperature value, the set temperature, the initial energy conversion value, the first current temperature value and the second current temperature value to obtain target energy conversion values ​​for the first temperature field and the second temperature field; determining the speed of the terminal fan of the central air conditioning according to the target energy conversion value.

[0005] In the related art, the ambient temperature is mainly measured by a temperature sensor located in the environment, and the air outlet of the terminal fan of the central air conditioner is controlled by comparing the ambient temperature with the set temperature; however, when the indoor population density suddenly increases or the weather temperature suddenly increases, it is difficult for the temperature sensor to promptly perceive the change in ambient temperature in a short period of time, resulting in a large lag time in the control of the air outlet of the terminal fan of the central air conditioner. Therefore, it is difficult to achieve more accurate control of the air outlet of the central air conditioner in the related art. Summary of the Invention

[0006] In order to overcome the problem in related technologies that it is difficult to achieve relatively accurate control of the air output of a central air conditioner, the present application provides a control method and system for a central air conditioner unit.

[0007] According to a first aspect of an embodiment of the present application, a control method for a central air-conditioning unit is provided, comprising: determining, when the central air-conditioning unit cools a target space, the cooling capacity of the central air-conditioning unit for the target space in different time periods; the cooling capacity is determined based on the inlet water temperature, return water temperature and water flow rate of the chilled water in the central air-conditioning unit within the time period; determining an evaluation value of the cooling capacity of the central air-conditioning unit for the target space in the current time period; the evaluation value is used to characterize the degree of difference between the cooling capacity for the target space in the current time period and the cooling capacity in multiple other time periods before the current time period; obtaining an initial cooling demand for the target space in the current time period, and determining a target cooling demand for the target space in the next time period of the current time period based on the initial cooling demand and the evaluation value corresponding to the current time period; and controlling the cooling of the target space by the central air-conditioning unit in the next time period based on the target cooling demand for the target space in the next time period.

[0008] In this way, compared with the temperature sensor set in the environment of the target space, the cooling capacity of the target space determined according to the temperature change of the chilled water can more sensitively sense the change of the ambient temperature. Therefore, the central air conditioner can better achieve cooling of the target space.

[0009] Optionally, the evaluation value of the cooling capacity of the target space in the current time period is determined in the following manner: for the target time period among multiple time periods, constructing the data points corresponding to the target time period based on the inlet water temperature, return water temperature and water flow of the chilled water in the target time period; clustering the first data point and multiple second data points to obtain the first average distance between the multiple clustering clusters after clustering; the first data point is the data point corresponding to the current time period, and the second data point is the data point corresponding to other time periods except the current time period; clustering the multiple second data points to obtain the second average distance between the multiple clustering clusters after clustering, and obtaining the evaluation value according to the ratio of the first average distance to the second average distance.

[0010] In this way, an evaluation value is obtained based on the ratio of the first average distance to the second average distance. The evaluation value can better characterize the difference between the cooling capacity of the target space in the current time period and the cooling capacity of multiple other time periods before the current time period, so as to achieve cooling of the target space.

[0011] Optionally, the evaluation value is obtained based on the ratio of the first average distance to the second average distance, including: determining the difference degree value between different sub-cooling capacities in different sub-time periods within the current time period in the cooling capacity of the central air-conditioning unit for the target space in the current time period; and dividing the ratio of the first average distance and the second average distance by the difference degree value to obtain the evaluation value.

[0012] Optionally, the initial cooling demand of the target space in the current time period is obtained in the following manner: obtaining the historical cooling demand of the target space in multiple historical time periods before the current time period, and predicting the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in the corresponding multiple historical time periods.

[0013] In this way, by predicting the initial cooling demand of the target space in the current time period, it is possible to better cool the users of the target space in the current time period and ensure the cooling experience of the users in the target space.

[0014] Optionally, the initial cooling demand of the target space in the current time period is predicted based on multiple historical cooling demands of the target space in corresponding multiple historical time periods, including: performing exponential smoothing prediction on the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in corresponding multiple historical time periods; or performing linear regression prediction on the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in corresponding multiple historical time periods.

[0015] Optionally, determining a target cooling demand for the target space in a next time period of the current time period according to the initial cooling demand and the evaluation value corresponding to the current time period includes: ,in, is the target cooling demand for the target space in the next time period of the current time period, is the initial cooling demand, is the cooling capacity of the central air-conditioning unit for the target space in the current time period, e is a natural constant, and H is the evaluation value corresponding to the current time period.

[0016] In this way, the target cooling demand of the central air-conditioning unit for the target space in the next time period of the current time period is determined based on the cooling capacity of the central air-conditioning unit for the target space in the current time period, the initial cooling demand and the evaluation value corresponding to the current time period. The target cooling demand can better meet the cooling demand.

[0017] Optionally, based on the target cooling demand for the target space in the next time period, the central air-conditioning unit is controlled to cool the target space in the next time period, including: based on the target cooling demand for the target space in the next time period, adjusting at least one of the following when the central air-conditioning unit cools the target space in the next time period: the inlet temperature of the chilled water, the water flow rate of the chilled water, and the cooling air supply volume of the central air-conditioning unit to the target space.

[0018] Optionally, the cooling capacity of the central air-conditioning unit for the target space in different time periods is obtained by: determining the temperature difference between the return water temperature and the inlet water temperature of the chilled water in the central air-conditioning unit; determining the cooling capacity of the central air-conditioning unit for the target space in the same time period based on the specific heat capacity of the chilled water, the temperature difference and the product of the water flow rate, so as to determine the cooling capacity of the central air-conditioning unit for the target space in different time periods.

[0019] Optionally, the method further includes: determining change information of the density of people in the target space during the current time period through image monitoring data of the target space obtained by the image sensor, and controlling the cooling of the target space by the central air-conditioning unit according to the change information.

[0020] In this way, based on the image monitoring data obtained by the image sensor, changes in the occupant density in the target space can be understood earlier, thereby enabling the central air conditioner to better cool the target space.

[0021] According to a second aspect of an embodiment of the present application, a control system for a central air-conditioning unit is provided, comprising: a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the steps of the control method for the central air-conditioning unit provided in the first aspect of the present application are implemented.

[0022] The technical solution provided by the embodiments of the present application may include the following beneficial effects: by determining the cooling capacity of the target space by the central air-conditioning unit in different time periods, since the cooling capacity is determined based on the inlet water temperature, return water temperature and water flow rate of the chilled water in the central air-conditioning unit within the time period, the chilled water can directly exchange heat with the air drawn from the target space in the chilled water coil, so that the cooling capacity of the target space determined based on the temperature change of the chilled water can more sensitively perceive the changes in ambient temperature. Therefore, based on the cooling capacity of the target space by the central air-conditioning unit in the current time period, the air outlet of the central air-conditioning unit can respond more quickly to changes in ambient temperature, shortening the lag time of controlling the air outlet of the terminal fan of the central air-conditioning; when there is a large change in the number of people indoors or the weather temperature changes significantly, the central air-conditioning can adapt to the changes in the target space more quickly, thereby improving the efficiency of cooling the target space.

[0023] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flow chart showing a method for controlling a central air-conditioning unit according to an exemplary embodiment;

[0025] Figure 2 The figure is a schematic structural diagram of a control system of a central air-conditioning unit according to an exemplary embodiment. DETAILED DESCRIPTION

[0026] First, a brief introduction is given to the application scenario of the embodiment of the present application. In the application scenario of the present application, the central air conditioner can cool the chilled water. The cooled chilled water comes into contact with the air extracted from the environment in the chilled water coil, so that the temperature of the contacted air is reduced, and the cooled air is blown out through the fan at the end to achieve cooling of the environment.

[0027] In order to control the air outlet of the terminal of the central air conditioner, the related art mainly sets a temperature sensor in the environment, and controls the air outlet temperature or air outlet speed of the terminal through the ambient temperature monitored by the temperature sensor.

[0028] However, since the temperature monitored by the temperature sensors installed in the environment mainly comes from the passive diffusion of air, in scenarios where there are large changes in indoor population density and other cooling demand changes, it is difficult for the temperature sensors in the environment to perceive such changes in a short period of time, making it difficult for the air outlet of the central air conditioner terminal to adapt to such large changes in cooling demand in a short period of time, causing users to feel hotter or colder in the environment where the central air conditioner terminal is located.

[0029] In order to solve the above technical problems, the present invention provides a control method and system for a central air-conditioning unit. Figure 1 FIG. 1 is a flow chart showing a method for controlling a central air-conditioning unit according to an exemplary embodiment. Figure 1 As shown, the method includes the following steps.

[0030] In step S101 , when the central air-conditioning unit is cooling the target space, the cooling capacity of the central air-conditioning unit for the target space in different time periods is determined.

[0031] The cooling capacity is determined based on the inlet water temperature, return water temperature and water flow rate of the chilled water in the central air conditioning unit within a time period.

[0032] When the central air conditioner cools the target space, it can cool the chilled water. The cooled chilled water enters the chilled water coil through the water inlet pipe. In the chilled water coil, the low-temperature chilled water comes into contact with the air drawn from the target space; the low-temperature chilled water absorbs heat from the air to form chilled water with a higher temperature. The chilled water that has completed the contact is re-cooled through the return pipe; the cooled air is blown out through the terminal fan of the central air conditioner to achieve cooling of the target space.

[0033] A first temperature sensor can be set on the inlet pipe of the chilled water coil of the chilled water, a second temperature sensor can be set on the return pipe of the chilled water coil of the chilled water, and a flow meter can be set on the inlet pipe or return pipe of the chilled water coil of the chilled water; the inlet temperature of the chilled water is obtained by the first temperature sensor, the outlet temperature of the chilled water is obtained by the second temperature sensor, and the water flow rate of the chilled water per unit time is obtained by the flow meter.

[0034] Through the heat exchange process between the chilled water and the air in the target space in the chilled water coil, the heat in the air is transferred to the chilled water; the heat exchanged between the chilled water and the air can be determined by the inlet water temperature, return water temperature and water flow rate of the chilled water within a certain period of time, that is, the cooling capacity of the chilled water on the air in the target space.

[0035] In one embodiment, the cooling capacity of the central air-conditioning unit for the target space in different time periods is obtained by: determining the temperature difference between the return water temperature and the inlet water temperature of the chilled water in the central air-conditioning unit; determining the cooling capacity of the central air-conditioning unit for the target space in the same time period based on the product of the specific heat capacity of the chilled water, the temperature difference and the water flow rate, so as to determine the cooling capacity of the central air-conditioning unit for the target space in different time periods.

[0036] The greater the temperature difference between the return water temperature and the inlet water temperature of the chilled water in the central air-conditioning unit, the greater the temperature increase of the chilled water after heat exchange with the air in the target space; the product of the specific heat capacity of the chilled water, the temperature difference and the water flow rate can be used to determine the cooling capacity of the central air-conditioning unit for the target space in the same time period.

[0037] Referring to the method for determining the cooling capacity of the target space by the central air-conditioning unit in the same time period, the cooling capacity of the target space by the central air-conditioning unit in different time periods can be determined for the different time periods when the central air-conditioning unit cools the target space.

[0038] In this way, the cooling capacity of the central air-conditioning unit for the target space in the same time period is determined based on the product of the specific heat capacity of the chilled water, the temperature difference and the water flow rate. The obtained cooling capacity can reflect the actual cooling effect of the central air-conditioning unit on the target space in the same time period.

[0039] In step S102, an evaluation value of the cooling capacity of the central air-conditioning unit for the target space in the current time period is determined.

[0040] The evaluation value is used to represent the difference between the cooling capacity of the target space in the current time period and the cooling capacity in multiple other time periods before the current time period.

[0041] For the target space to be cooled by the central air conditioner, in order to ensure that the ambient temperature in the target space is within the specified temperature range, the inlet temperature of the chilled water in the chilled water coil and the water flow rate of the chilled water per unit time can be controlled, and the heat exchanged between the chilled water and the air in the target space in the chilled water coil per unit time can be controlled, thereby achieving the control of the outlet air temperature of the terminal fan of the central air conditioner.

[0042] The occupant density or equipment density in the target space may change significantly in a short period of time. For example, the number of occupants in the target space may increase from 2 to 50 in a short period of time. Alternatively, in order to maintain a cool environment while keeping food warm, users may choose to turn on the heating device in the target space to heat the food so that they can eat heated food in a cool environment, increasing the cooling demand in the target space. Alternatively, the equipment in the target space may be operating in a higher-heating state during the same time period.

[0043] As the density of people or the density of heat-generating components in the target space increases in a short period of time, the central air conditioner can provide a higher cooling capacity to the target space to maintain the consistency of the temperature in the target space before and after the change in the density of people or the density of heat-generating components, thereby preventing people in the target space from feeling too hot or too cold.

[0044] As the density of people or heat-generating components in the target space increases in a short period of time, the temperature of the air extracted from the target space that the chilled water contacts rises. While the inlet temperature and water flow rate of the chilled water remain unchanged, the return temperature of the chilled water after heat exchange with the air rises. Based on the inlet temperature, return temperature and water flow rate of the chilled water in the central air-conditioning unit, it can be determined that the cooling capacity of the central air-conditioning for the target space has increased.

[0045] Compared with before the increase in the population density or the density of heat-generating components in the target space, the difference between the cooling capacity of the central air-conditioning for the target space and the cooling capacity of the central air-conditioning in other time periods is greater after the sudden increase in the population density or the density of heat-generating components in the target space. Therefore, the evaluation value of the cooling capacity of the central air-conditioning unit for the target space in the current time period can be determined, so as to determine whether there is a concentrated change in the population density or the density of heat-generating components in the current time period through the evaluation value.

[0046] Since the air for heat exchange between the chilled water and the target space is extracted from the target space, and the chilled water and the air in the target space exchange heat through components with higher thermal conductivity such as copper tubes, compared with the heat conduction performed by static air, the sensor used to measure the return water temperature of the chilled water in the chilled water coil can sense the temperature changes caused by the density of people or equipment in the target space earlier than the temperature sensor placed in the target space. Therefore, the cooling capacity of the central air conditioner for the target space can be adapted to the changes in the density of people or equipment in the target space more quickly.

[0047] In one embodiment, the evaluation value of the cooling capacity of the target space in the current time period is determined in the following manner: for the target time period among multiple time periods, based on the inlet water temperature, return water temperature and water flow of the chilled water in the target time period, constructing the data points corresponding to the target time period; clustering the first data point and multiple second data points to obtain the first average distance between the multiple clustering clusters after clustering; the first data point is the data point corresponding to the current time period, and the second data point is the data point corresponding to other time periods except the current time period; clustering the multiple second data points to obtain the second average distance between the multiple clustering clusters after clustering, and obtaining the evaluation value according to the ratio of the first average distance to the second average distance.

[0048] The durations corresponding to the multiple time periods are the same. For example, the durations corresponding to the multiple time periods may all be equal to a preset duration such as 30 seconds or 40 seconds, so as to avoid the influence of different durations on the judgment of the cooling capacity.

[0049] The inlet water temperature, return water temperature and water flow rate of the chilled water within the target time period can be used as three different evaluation dimensions of the data points. Different data points correspond to different time periods when the central air conditioner cools the target space.

[0050] Clustering the first data point and multiple second data points to obtain a first average distance between the multiple clusters after clustering. The first average distance can be equal to the average distance between the clusters after clustering the first data point and the multiple second data points; the first average distance can reflect the degree of dispersion between the clusters obtained when the data points corresponding to the current time period participate in clustering.

[0051] Clustering is performed on multiple second data points to obtain a second average distance between the multiple clusters after clustering, where the second data points are data points corresponding to time periods other than the current time period; for example, the first data point corresponds to the current time period, and the multiple second data points respectively correspond to multiple historical time periods before the current moment.

[0052] The second average distance is equal to the average distance between multiple clusters obtained after clustering the multiple second data points. The second average distance can reflect the degree of dispersion between clusters obtained when the data points corresponding to the current time period do not participate in clustering.

[0053] Since the first average distance can reflect the degree of dispersion between the clusters obtained when the data points corresponding to the current time period participate in clustering, and the second average distance can reflect the degree of dispersion between the clusters obtained when the data points corresponding to the current time period do not participate in clustering, the ratio of the first average distance to the second average distance can better reflect the degree of difference between the first data point corresponding to the current time period and the second data point corresponding to other time periods, thereby reflecting the degree of difference between the cooling capacity of the target space in the current time period and the cooling capacity in other time periods.

[0054] In this way, since the first average distance reflects the discreteness between the clusters obtained when the data points corresponding to the current time period participate in clustering, and the second average distance reflects the discreteness between the clusters obtained when the data points corresponding to the current time period do not participate in clustering, the evaluation value is obtained according to the ratio of the first average distance to the second average distance. The evaluation value can better characterize the degree of difference between the cooling capacity of the target space in the current time period and the cooling capacity of multiple other time periods before the current time period.

[0055] In one embodiment, the evaluation value is obtained based on the ratio of the first average distance to the second average distance, including: determining the difference degree value between different sub-cooling capacities in different sub-time periods within the current time period in the cooling capacity of the central air-conditioning unit for the target space in the current time period; and dividing the ratio of the first average distance and the second average distance by the difference degree value to obtain the evaluation value.

[0056] In the cooling capacity of the central air-conditioning unit for the target space in the current time period, the difference degree value between different sub-cooling capacities in different sub-time periods within the current time period is used to represent the difference degree between different sub-cooling capacities in different sub-time periods within the current time period.

[0057] For example, when the current time period is 30 seconds, the six sub-cooling capacities of the central air-conditioning unit in six sub-time periods, namely, from 0 seconds to 5 seconds, from 5 seconds to 10 seconds, from 10 seconds to 15 seconds, from 15 seconds to 20 seconds, from 20 seconds to 25 seconds, and from 25 seconds to 30 seconds, can be determined respectively.

[0058] The six sub-cooling capacities corresponding to the six sub-time periods may be compared in pairs to determine the difference between the different sub-cooling capacities in different sub-time periods within the current time period.

[0059] If the cooling capacity of the target space is relatively stable in different sub-time periods of the current time period, and the cooling capacity of the target space in the current time period differs greatly from that in multiple historical moments before the current moment, then the cooling capacity of the target space is more likely to have undergone a step-like change at the start of the current time period, for example, a sudden increase or decrease in a short period of time. Such a step-like change is more likely to be caused by a sudden increase or decrease in the density of people or heat-generating components in the target space in a short period of time.

[0060] For example, the number of people in the target space increases from 2 to 50 within 30 seconds, or the number of heating components in a heating state in the target space increases from 2 to 10 within 30 seconds.

[0061] In this way, the ratio of the first average distance and the second average distance is divided by the difference degree value to obtain an evaluation value. The obtained evaluation value can better reflect whether the density of people or heating components in the target space has changed significantly in a short period of time.

[0062] In step S103, the initial cooling demand of the target space in the current time period is obtained, and the target cooling demand for the target space in the next time period of the current time period is determined based on the initial cooling demand and the evaluation value corresponding to the current time period.

[0063] The initial cooling demand of the target space in the current time period can be determined based on the cooling capacity of the target space in at least one historical time period before the current time period. When the density of people or the density of heat-generating components in the target space does not change significantly in a short period of time, the temperature of the target space can be kept stable by providing a relatively stable cooling capacity for the target space. Therefore, based on the cooling capacity of the target space in at least one historical time period before the current time period, an initial cooling demand with a high reference value can be determined for the target space in the current time period.

[0064] When the density of people or the density of heat-generating components in the target space does not change significantly in a short period of time, the central air conditioner cools the target space according to the initial cooling demand, so as to keep the temperature of the target space within the specified temperature range, thereby preventing people in the target space from feeling too cold or too hot.

[0065] When the density of people or the density of heat-generating components in the target space changes significantly in a short period of time, if the central air conditioner continues to cool the target space according to the initial cooling demand, it will be difficult to meet the actual cooling capacity required by the target space in the next time period of the current time period. Therefore, based on the initial cooling demand, a more matching target cooling demand can be determined to control the central air conditioner to cool the target space according to the target cooling demand.

[0066] In one embodiment, the initial cooling demand of the target space in the current time period is obtained by obtaining the historical cooling demand of the target space in multiple historical time periods before the current time period, and predicting the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in the corresponding multiple historical time periods.

[0067] The historical cooling demand of the target space in the historical time period before the current time period is the result of the user's control over the cooling capacity of the central air conditioner in the target space, or the result of the central air conditioner's own control over the cooling capacity of the target space; for example, when the target space requires a lower temperature, a higher cooling capacity is provided for the target space, or when the target space requires a higher temperature, a lower cooling capacity is provided for the target space.

[0068] When the population density of the target space has not changed significantly in the historical time period, the historical cooling capacity of the target space in the historical time period of the current time period can meet the historical cooling demand of the target space in the historical time period of the current time period. Therefore, based on the multiple historical cooling demands of the target space in the corresponding multiple historical time periods, the predicted initial cooling demand of the target space in the current time period has a high probability of also being able to make the actual cooling capacity meet the cooling demand in the current time period.

[0069] In this way, the initial cooling demand of the target space in the current time period is predicted based on the multiple historical cooling demands of the target space in the corresponding multiple historical time periods, so that the users or equipment to be cooled in the target space can be better cooled in the current time period.

[0070] In one embodiment, an initial cooling demand of a target space in a current time period is predicted based on multiple historical cooling demands of the target space in corresponding multiple historical time periods, including: performing exponential smoothing prediction on the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in corresponding multiple historical time periods; or performing linear regression prediction on the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in corresponding multiple historical time periods.

[0071] Exponential smoothing or linear regression can reflect the changes in cooling demand over a certain period of time. By using the multiple historical cooling demands of the target space in the corresponding multiple historical time periods, linear regression prediction or exponential smoothing prediction is performed on the initial cooling demand of the target space in the current time period. The obtained prediction results have a high probability of meeting the cooling demand of the target space in the current time period.

[0072] In addition to using exponential smoothing prediction or linear regression to predict the initial cooling demand of the target space in the current time period, a pre-trained prediction model can also be used to predict the initial cooling demand of the target space in the current time period. The prediction model can be trained using multiple historical cooling demands of the target space in corresponding historical time periods.

[0073] In one embodiment, determining a target cooling demand for a target space in a next time period of the current time period based on the initial cooling demand and the evaluation value corresponding to the current time period includes: ,in, is the target cooling demand for the target space in the next time period of the current time period, is the initial cooling demand, is the cooling capacity of the central air-conditioning unit for the target space in the current time period, e is a natural constant, and H is the evaluation value corresponding to the current time period.

[0074] Since the cooling capacity of the central air-conditioning unit for the target space in the current time period is determined based on the inlet water temperature, return water temperature and water flow of the central air-conditioning in the target space, the chilled water can sense the changes in the cooling demand of the target space by exchanging heat with the air extracted from the target space.

[0075] When the initial cooling demand in the current time period is relatively stable compared to the historical cooling demand at the previous moment, and the cooling capacity of the central air-conditioning unit for the target space increases in the current time period, it means that the actual cooling demand of the target space in the current time period is increasing. The target space can be provided with a higher cooling capacity to adapt to the change in the actual cooling demand of the target space.

[0076] H is the evaluation value corresponding to the current time period, which can represent the difference between the cooling capacity of the target space in the current time period and the cooling capacity of multiple other time periods before the current time period. The larger the value of H is, the greater the change in the actual demand for cooling capacity of the target space in the current time period. It can reflect the change direction of the cooling capacity of the target space in the current time period. Therefore, the calculation formula of the target cooling demand can consider the change direction and change amplitude of the cooling capacity demand of the target space in the current time period.

[0077] The greater the change in the cooling capacity demand of the target space in the current time period, the greater the adjustment required for the cooling capacity of the target space; or, the greater the difference between the initial cooling capacity demand of the target space in the current time period determined based on the historical time period and the actual cooling capacity continued to be provided by the central air conditioner in the current time period, the greater the impact of the change in the density of people or heat-generating components in the target space on the cooling demand, and therefore, the greater the adjustment required for the cooling capacity of the target space.

[0078] In this way, the target cooling demand for the target space in the next time period of the current time period can be determined based on the cooling capacity of the central air-conditioning unit for the target space in the current time period, the initial cooling demand and the evaluation value corresponding to the current time period. The target cooling demand can better meet the cooling demand of the target space in the next time period of the current time period.

[0079] In step S104, the central air-conditioning unit is controlled to cool the target space in the next time period according to the target cooling demand for the target space in the next time period.

[0080] The target cooling demand for the target space determined in the embodiment of the present application can adapt to changes in the population density or weather temperature of the target space in a timely manner. Therefore, according to the target cooling demand for the target space in the next time period, the central air-conditioning unit is controlled to cool the target space in the next time period, which can ensure the stability of the cooling effect of the central air-conditioning unit on the target space.

[0081] In one embodiment, the cooling of the target space by the central air-conditioning unit in the next time period is controlled according to the target cooling demand for the target space in the next time period, including: adjusting at least one of the following when the central air-conditioning unit cools the target space in the next time period according to the target cooling demand for the target space in the next time period: the inlet temperature of the chilled water, the water flow rate of the chilled water, and the cooling air supply volume of the central air-conditioning unit to the target space.

[0082] By adjusting the cooling parameters of the central air conditioner when cooling the target space, it can adapt to changes in the density of people or the density of heat-generating components in the target space, thereby cooling the target space more efficiently and avoiding over-cooling or under-cooling.

[0083] For example, if the occupant density increases within a short period of time, in order to ensure the cooling effect on the target space, the chilled water inlet temperature can be lowered, the chilled water flow rate can be increased, or the cooling air supply volume can be increased.

[0084] When the occupancy density decreases within a short period of time, for example, after a meeting, in order to maintain a stable cooling effect on the target space and avoid energy waste, the chilled water inlet temperature can be increased, the chilled water flow rate can be reduced, or the cooling air supply volume can be reduced.

[0085] In one embodiment, the image monitoring data of the target space obtained by the image sensor can also be used to determine the change information of the density of people in the target space during the current time period, and the central air-conditioning unit can be controlled to cool the target space according to the change information.

[0086] For example, at least one image sensor can be set up in the target space. The image monitoring data obtained by the image sensor can be used to determine the number of people in the target space at different times, so as to determine the change information of the density of people in the target space in the current time period; the change information is used to characterize the change of the density of people in the target space.

[0087] Controlling the cooling of the target space by the central air-conditioning unit according to the change information may include: when the change information indicates that the density of people in the target space has increased, the cooling capacity of the central air-conditioning unit for the target space can be increased; or when the change information indicates that the density of people in the target space has decreased, the cooling capacity of the central air-conditioning unit for the target space can be reduced.

[0088] Compared to sensing the occupant density in a target space through the inlet and return temperatures of the chilled water in the central air-conditioning unit, image monitoring data acquired by the image sensor can detect changes in occupant density earlier. Therefore, the cooling capacity of the central air-conditioning unit for the target space can better meet the user's cooling experience.

[0089] Figure 2 FIG. 1 is a structural diagram of a control system 1000 of a central air-conditioning unit according to an exemplary embodiment. Figure 2 The control system 1000 of the central air-conditioning unit includes: a processor 1100 and a memory 1200, wherein the memory 1200 stores computer program instructions, and when the computer program instructions are executed by the processor 1100, all or part of the steps of the control method of the central air-conditioning unit in this application are implemented.

[0090] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein, and the description and examples are to be considered merely as exemplary.

[0091] It will be understood that the present application is not limited to the exact construction that has been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof.

Claims

1. A control method for a central air-conditioning unit, characterized in that: include: When the central air-conditioning unit cools the target space, determining the cooling capacity of the central air-conditioning unit for the target space in different time periods; The cooling capacity is determined based on the inlet water temperature, return water temperature and water flow rate of the chilled water in the central air conditioning unit within a time period; Determine the evaluation value of the cooling capacity of the central air conditioning unit for the target space in the current time period, which is determined by: for a target time period among multiple time periods, construct a data point corresponding to the target time period based on the inlet water temperature, return water temperature, and water flow rate of the chilled water in the target time period; Clustering the first data point and the plurality of second data points to obtain a first average distance between the plurality of clusters after clustering; The first data point is a data point corresponding to the current time period, and the second data point is a data point corresponding to a time period other than the current time period; Clustering the plurality of second data points to obtain a second average distance between the plurality of clusters after clustering, and obtaining the evaluation value based on a ratio of the first average distance to the second average distance, including: determining a degree of difference between different sub-cooling capacities in different sub-time periods within the current time period, in the cooling capacity of the central air-conditioning unit for the target space during the current time period; dividing the ratio of the first average distance to the second average distance by the degree of difference to obtain the evaluation value; the evaluation value is used to represent the degree of difference between the cooling capacity for the target space during the current time period and the cooling capacities during multiple other time periods before the current time period; Obtaining an initial cooling demand of the target space in the current time period, and determining a target cooling demand for the target space in the next time period of the current time period based on the initial cooling demand and the evaluation value corresponding to the current time period; According to the target cooling demand for the target space in the next time period, the central air-conditioning unit is controlled to cool the target space in the next time period.

2. The control method of the central air-conditioning unit according to claim 1, characterized in that: The initial cooling demand of the target space in the current time period is obtained in the following way: The historical cooling demand of the target space in multiple historical time periods before the current time period is obtained, and the initial cooling demand of the target space in the current time period is predicted based on the multiple historical cooling demand of the target space in the corresponding multiple historical time periods.

3. The control method of the central air-conditioning unit according to claim 2, characterized in that: Based on multiple historical cooling demands of the target space in corresponding historical time periods, the initial cooling demand of the target space in the current time period is predicted, including: Based on the multiple historical cooling demands of the target space in the corresponding multiple historical time periods, an exponential smoothing forecast is performed on the initial cooling demand of the target space in the current time period; Alternatively, a linear regression prediction is performed on the initial cooling demand of the target space in the current time period based on multiple historical cooling demands of the target space in corresponding multiple historical time periods.

4. The control method of a central air-conditioning unit according to claim 1, characterized in that: Determining a target cooling demand for the target space in a next time period of the current time period according to the initial cooling demand and the evaluation value corresponding to the current time period includes: ,in, is the target cooling demand for the target space in the next time period of the current time period, is the initial cooling demand, is the cooling capacity of the central air-conditioning unit for the target space in the current time period, e is a natural constant, and H is the evaluation value corresponding to the current time period.

5. The control method of a central air-conditioning unit according to claim 1, characterized in that: Controlling the central air-conditioning unit to cool the target space in the next time period according to the target cooling demand for the target space in the next time period includes: According to the target cooling demand for the target space in the next time period, the central air conditioning unit is adjusted to cool the target space in the next time period by at least one of the following: The inlet temperature of the chilled water, the flow rate of the chilled water, and the cooling air supply volume of the central air-conditioning unit to the target space.

6. The control method of a central air-conditioning unit according to claim 1, characterized in that: The cooling capacity of the central air-conditioning unit for the target space in different time periods is obtained in the following ways: Determine the temperature difference between the return and inlet temperatures of chilled water in central air conditioning units; Based on the specific heat capacity of chilled water, the temperature difference and the product of water flow, the cooling capacity of the central air-conditioning unit for the target space in the same time period is determined, so as to determine the cooling capacity of the central air-conditioning unit for the target space in different time periods.

7. The control method of a central air-conditioning unit according to claim 1, characterized in that: The method further comprises: The image monitoring data of the target space acquired by the image sensor is used to determine the change information of the density of people in the target space during the current time period, and the central air-conditioning unit is controlled to cool the target space according to the change information.

8. A control system for a central air-conditioning unit, characterized in that: include: A processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the control method of the central air-conditioning unit according to any one of claims 1 to 7 is implemented.

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