Control method and system for central air conditioning unit

Abstract

The invention relates to the technical field of equipment control, in particular to a control method and system for a central air conditioning unit. The method comprises the steps that under the condition that a central air conditioning unit refrigerates a target space, the refrigerating capacity of the central air conditioning unit on the target space in different time periods is determined; the evaluation value of the central air conditioning unit on the refrigerating capacity of the target space in the current time period is determined; the initial refrigeration demand quantity of the target space in the current time period is obtained, and the target refrigeration demand quantity of the target space in the next time period of the current time period is determined according to the initial refrigeration demand quantity and the evaluation value corresponding to the current time period; and according to the target refrigeration demand for the target space in the next time period, the central air conditioning unit is controlled to refrigerate the target space in the next time period. According to the technical scheme, the air outlet of the central air conditioning unit can respond to the change of the environment temperature more quickly.

Description

Technical Field

[0001] This application relates to the technical field of equipment control, and particularly 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. The central air-conditioning unit can achieve the refrigeration of the space to be cooled and maintain the temperature of the environment to be cooled within a preset temperature range.

[0003] For example, when the central air-conditioning unit is performing refrigeration, 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, reducing the temperature of the chilled water. The cooled chilled water is transported through pipes to the chilled water coil in the air handling unit. Indoor air is blown by a fan over the chilled water coil, and the heat in the air is transferred to the chilled water, cooling the air. The cooled air is blown into the environment to be cooled by the terminal fan, achieving the refrigeration of the space to be cooled.

[0004] In order to achieve the control of the central air-conditioning, in the Chinese patent application document with the publication number CN117346307A, a control method for the terminal fan of the central air-conditioning is provided, 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 form a first temperature field; determining a working mode according to the first initial temperature value and the set temperature; after a preset time interval, obtaining a first current temperature value and a second current temperature value detected by multiple sensors. The first current temperature value and the second current temperature value form a second temperature field; calculating the target energy conversion value of the first temperature field and the second temperature field based on the working mode for 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; and determining the rotation 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 temperature sensors located in the environment, and the air outlet of the terminal fan of the central air-conditioning is controlled by comparing the ambient temperature with the set temperature. However, when the indoor population density suddenly rises or the weather temperature suddenly rises, it is difficult for the temperature sensors to promptly sense the change in the ambient temperature within a short time, resulting in a relatively large lag time in controlling the air outlet of the terminal fan of the central air-conditioning. Therefore, it is difficult to achieve relatively accurate control of the air outlet of the central air-conditioning in the related art. Summary of the Invention

[0006] To overcome the problem in the related art that it is difficult to accurately control the air outlet of a central air conditioner, the present application provides a control method and system for a central air conditioner unit.

[0007] According to the first aspect of the embodiments of the present application, a control method for a central air conditioner unit is provided, including: when the central air conditioner unit cools a target space, determining the cooling capacity of the central air conditioner unit for the target space in different time periods respectively; the cooling capacity is determined according to the inlet water temperature, return water temperature and water flow rate of the chilled water in the central air conditioner unit during the time period; determining an evaluation value of the cooling capacity of the central air conditioner unit for the target space in the current time period; the evaluation value is used to characterize the difference degree between the cooling capacity of the current time period for the target space and the cooling capacities of multiple other time periods before the current time period; obtaining the initial cooling demand of the target space in the current time period, and determining the target cooling demand of the next time period for the target space according to the initial cooling demand and the evaluation value corresponding to the current time period; controlling the central air conditioner unit to cool the target space in the next time period according to the target cooling demand of the next time period for the target space.

[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 environmental temperature. Therefore, the central air conditioner can better realize the cooling of the target space.

[0009] Optionally, the evaluation value of the cooling capacity of the central air conditioner unit for the target space in the current time period is determined by the following method: for a target time period among multiple time periods, constructing a data point corresponding to the target time period according to 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 multiple second data points to obtain the first average distance between multiple clustered clusters; the first data point is the data point corresponding to the current time period, and the second data points are the data points corresponding to other time periods except the current time period; clustering the multiple second data points to obtain the second average distance between multiple clustered clusters, and obtaining the evaluation value according to the ratio of the first average distance to the second average distance.

[0010] In this way, the evaluation value is obtained according to the ratio of the first average distance to the second average distance, and the evaluation value can better characterize the difference degree between the cooling capacity of the current time period for the target space and the cooling capacities of multiple other time periods before the current time period, so as to realize the cooling of the target space.

[0011] Optionally, obtaining the evaluation value according to the ratio of the first average distance to the second average distance includes: determining, among the cooling capacities 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; 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 by the following method: obtaining the historical cooling demands 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 according to the 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 in the target space in the current time period and ensure the cooling experience of the users in the target space.

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

[0015] Optionally, determining the target cooling demand of the target space in the 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: , where is the target cooling demand of 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 the 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 according to 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, and the target cooling demand can better meet the cooling demand.

[0017] Optionally, controlling the central air-conditioning unit to cool the target space in the next time period according to the target cooling demand of the target space in the next time period includes: 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 of 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 the following method: 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 according to 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.

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

[0020] In this way, according to the image monitoring data obtained by the image sensor, the change of the density of people in the target space can be understood earlier. Therefore, the central air-conditioning can cool the target space better.

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

[0022] The technical solutions provided by the embodiments of the present application may include the following beneficial effects: By determining the cooling capacity of the central air-conditioning unit for the target space in different time periods, since the cooling capacity is determined according to the inlet water temperature, the return water temperature, and the water flow rate of the chilled water in the central air-conditioning unit during 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 according to the temperature change of the chilled water can more sensitively sense the change of the environmental temperature. Therefore, according to the cooling capacity of the central air-conditioning unit for the target space in the current time period, the air outlet of the central air-conditioning unit can respond to the change of the environmental temperature faster, and shorten the lag time of controlling the air outlet of the end fan of the central air-conditioning; when there is a large change in the number of people in the room or a large change in the weather temperature, the central air-conditioning can adapt to the change of the target space faster, and improve the efficiency of cooling the target space.

[0023] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a flowchart of a control method for a central air-conditioning unit shown according to an exemplary embodiment; Figure 2 is a schematic structural diagram of a control system for a central air-conditioning unit shown according to an exemplary embodiment. DETAILED DESCRIPTION

[0025] First, a simple introduction to the application scenario of the embodiments of this application is given. In the application scenario of this application, the central air conditioner can cool the chilled water. The cooled chilled water contacts the air extracted from the environment in the chilled water coil, reducing the temperature of the contacted air, and blowing out the cooled air through the terminal fan to achieve the cooling of the environment.

[0026] In order to control the air outlet of the terminal of the central air conditioner, in the related art, mainly by setting temperature sensors in the environment, and controlling the air outlet temperature or air outlet speed of the terminal through the environmental temperature monitored by the temperature sensors.

[0027] However, since the temperature monitored by the temperature sensors set in the environment mainly comes from the passive spread of air, in scenarios where there are large fluctuations in the indoor population density and other large changes in the cooling demand occur, it is difficult for the temperature sensors in the environment to perceive this change in a short time, making it difficult for the air outlet of the terminal of the central air conditioner to adapt to this large change in the cooling demand in a short time, making users feel hotter or colder in the environment where the terminal of the central air conditioner is located.

[0028] To solve the above technical problems, the embodiments of this application provide a control method and system for a central air-conditioning unit, Figure 1 is a flowchart of a control method for a central air-conditioning unit shown according to an exemplary embodiment, as Figure 1 shown, the method includes the following steps.

[0029] In step S101, when the central air-conditioning unit cools the target space, determine the cooling capacity of the central air-conditioning unit for the target space in different time periods.

[0030] The cooling capacity is determined according to 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.

[0031] When the central air conditioner cools the target space, it can cool the chilled water. The chilled water after cooling enters the chilled water coil through the inlet pipeline. In the chilled water coil, the low-temperature chilled water contacts the air extracted from the target space; the low-temperature chilled water absorbs the heat from the air to form warmer chilled water. The chilled water after the contact process is re-cooled through the return pipeline; the cooled air is then blown out by the end fan of the central air conditioner to achieve the cooling of the target space.

[0032] A first temperature sensor can be set on the inlet pipeline of the chilled water coil of the chilled water, a second temperature sensor can be set on the return pipeline of the chilled water coil of the chilled water, and a flow meter can be set on the inlet pipeline or the return pipeline of the chilled water coil of the chilled water; the inlet temperature of the chilled water is obtained through the first temperature sensor, the outlet temperature of the chilled water is obtained through the second temperature sensor, and the water flow rate of the chilled water per unit time is obtained through the flow meter.

[0033] 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; through the inlet temperature, return temperature and water flow rate of the chilled water in a certain period of time, the heat of the heat exchange between the chilled water and the air can be determined, that is, the cooling capacity of the chilled water for the air in the target space.

[0034] In one embodiment, the cooling capacity of the central air conditioner unit for the target space at different time periods is obtained through the following method: determining the temperature difference between the return water temperature and the inlet water temperature of the chilled water in the central air conditioner unit; according to the product of the specific heat capacity, temperature difference and water flow rate of the chilled water, determining the cooling capacity of the central air conditioner unit for the target space in the same time period, so as to determine the cooling capacity of the central air conditioner unit for the target space at different time periods respectively.

[0035] The greater the temperature difference between the return water temperature and the inlet water temperature of the chilled water in the central air conditioner unit, the greater the temperature increase of the chilled water after the heat exchange between the chilled water and the air in the target space; the product of the specific heat capacity, temperature difference and water flow rate of the chilled water can be used as the cooling capacity of the central air conditioner unit for the target space in the same time period.

[0036] Referring to the determination method of the cooling capacity of the central air conditioner unit for the target space in the same time period, for different time periods when the central air conditioner unit cools the target space, the cooling capacity of the central air conditioner unit for the target space at different time periods can be determined respectively.

[0037] In this way, according to the product of the specific heat capacity, temperature difference and water flow rate of the chilled water, the cooling capacity of the central air conditioner unit for the target space in the same time period is determined, and the obtained cooling capacity can reflect the actual cooling effect of the central air conditioner unit on the target space in the same time period.

[0038] In step S102, determine the evaluation value of the cooling capacity of the central air-conditioning unit for the target space in the current time period.

[0039] The evaluation value is used to characterize the difference degree between the cooling capacity of the target space in the current time period and the cooling capacities in multiple other time periods before the current time period.

[0040] For the target space cooled by the central air-conditioning, in order to ensure that the environmental temperature in the target space is within the specified temperature range, the heat exchange amount per unit time between the chilled water and the air in the target space in the chilled water coil can be controlled by controlling the inlet temperature of the chilled water in the chilled water coil and the water flow rate of the chilled water per unit time, so as to control the outlet temperature of the air of the end fan of the central air-conditioning.

[0041] The personnel density or equipment density in the target space may change greatly in a short time; for example, the number of people in the target space rises from the original 2 to 50 in a short time; or, in order to balance the coolness of the environment and the heat preservation of food, so as to eat heated food in a cool environment, the user chooses to turn on the heating device in the target space to heat the food, resulting in an increase in the cooling demand of the target space; or, the equipment in the target space is in a higher heat-generating working state in the same time period.

[0042] As the personnel density or the density of heat-generating components in the target space rises in a short time, the central air-conditioning can maintain the temperature consistency in the target space before and after the change in the personnel density or the density of heat-generating components by providing a higher cooling capacity for the target space, and avoid the people in the target space feeling too hot or too cold.

[0043] As the personnel density or the density of heat-generating components in the target space rises in a short time, the temperature of the air extracted from the target space in contact with the chilled water rises. Without changing the inlet temperature and water flow rate of the chilled water, the return water temperature of the chilled water after heat exchange with the air rises. According to the inlet temperature, return water 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 increases.

[0044] Compared with before the sudden rise in the personnel density or the density of heat-generating components in the target space, after the sudden rise in the personnel density or the density of heat-generating components in the target space, the difference degree between the cooling capacity of the central air-conditioning for the target space and the cooling capacities of the central air-conditioning in other time periods is greater. 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 personnel density or the density of heat-generating components in the current time period through the evaluation value.

[0045] Since the air for heat exchange between the chilled water and the target space is extracted from the target space, and the chilled water exchanges heat with the air in the target space through components with higher heat conductivity such as copper pipes, compared with the heat conduction of static air, the sensor for measuring the return water temperature of the chilled water in the chilled water coil can sense the temperature change caused by the personnel density or equipment density in the target space earlier than the temperature sensor placed in the target space. Therefore, the central air conditioner can adapt the cooling capacity of the target space to the change of the personnel density or equipment density in the target space faster.

[0046] In one embodiment, the evaluation value of the cooling capacity of the target space in the current time period is determined as follows: for the target time period among multiple time periods, data points corresponding to the target time period are constructed according to the inlet water temperature, return water temperature and water flow rate of the chilled water in the target time period; clustering is performed on the first data point and multiple second data points to obtain the first average distance between the multiple clustered clusters; 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 is performed on the multiple second data points to obtain the second average distance between the multiple clustered clusters, and the evaluation value is obtained according to the ratio of the first average distance to the second average distance.

[0047] The durations corresponding to multiple time periods are the same. For example, the durations corresponding to multiple time periods can all be equal to a preset duration such as 30 seconds or 40 seconds set in advance, so as to avoid the influence of different durations on the judgment of the cooling capacity.

[0048] The inlet water temperature, return water temperature and water flow rate of the chilled water in the target time period can be used as three different evaluation dimensions of the data points respectively, and different data points correspond to different time periods when the central air conditioner cools the target space.

[0049] Clustering is performed on the first data point and multiple second data points to obtain the first average distance between the multiple clustered clusters. The first average distance can be equal to the average distance between the clusters after clustering the first data point and multiple second data points; the first average distance can reflect the degree of dispersion between the clusters obtained when the data point corresponding to the current time period participates in clustering.

[0050] Clustering is performed on the multiple second data points to obtain the second average distance between the multiple clustered clusters. The second data point is the data point corresponding to other time periods except the current time period; for example, the first data point corresponds to the current time period, and the multiple second data points correspond to multiple historical time periods before the current moment.

[0051] The second average distance is equal to the average distance between multiple clusters obtained after clustering multiple second data points. 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 the clustering.

[0052] 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 the 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 the clustering, therefore, the ratio of the first average distance to the second average distance can better reflect the degree of difference between the first data points corresponding to the current time period and the second data points 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.

[0053] 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 the 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 the 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 capacities in multiple other time periods before the current time period.

[0054] In one embodiment, obtaining the evaluation value according to the ratio of the first average distance to the second average distance includes: determining the degree of difference 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; dividing the ratio of the first average distance and the second average distance by the degree of difference value to obtain the evaluation value.

[0055] The degree of difference 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 is used to characterize the degree of difference between different sub-cooling capacities in different sub-time periods within the current time period.

[0056] For example, when the duration of the current time period is equal to 30 seconds, the central air-conditioning unit can respectively determine six sub-cooling capacities in six sub-time periods from the 0th second to the 5th second, from the 5th second to the 10th second, from the 10th second to the 15th second, from the 15th second to the 20th second, from the 20th second to the 25th second, and from the 25th second to the 30th second.

[0057] The six sub-cooling capacities corresponding to the six sub-time periods can be compared pairwise to determine the degree of difference value between different sub-cooling capacities in different sub-time periods within the current time period.

[0058] If the cooling capacity of the target space is relatively stable in different sub - time periods of the current time period, and the difference between the cooling capacity of the target space in the current time period and that at multiple historical moments before the current moment is relatively large, then it is more likely that the cooling capacity of the target space has undergone a step - like change at the start moment of the current time period. For example, it may suddenly increase or suddenly decrease within a short period of time. Such a step - like change is more likely caused by a sudden increase or decrease in the density of people or heating components in the target space within a short period of time.

[0059] 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 the target space in the heating state increases from 2 to 10 within 30 seconds.

[0060] In this way, by dividing the ratio of the first average distance and the second average distance by the difference degree value to obtain an evaluation value, the obtained evaluation value can better reflect whether there has been a large - scale change in the density of people or heating components in the target space within a short period of time.

[0061] In step S103, obtain the initial cooling demand of the target space in the current time period, and determine the target cooling demand of the target space for the next time period of the current time period according to the initial cooling demand and the evaluation value corresponding to the current time period.

[0062] The initial cooling demand of the target space in the current time period can be determined according to the cooling capacity of the target space in at least one historical time period before the current time period; in the case where the density of people or heating components in the target space does not change significantly within a short period of time, by providing a relatively stable cooling capacity for the target space, the temperature of the target space can be kept stable. Therefore, according to the cooling capacity of the target space in at least one historical time period before the current time period, an initial cooling demand with relatively high reference value can be determined for the target space in the current time period.

[0063] In the case where the density of people or heating components in the target space does not change significantly within a short period of time, the central air - conditioner cools the target space according to the initial cooling demand, and the temperature of the target space can be kept within the specified temperature range, thus preventing people in the target space from feeling too cold or too hot.

[0064] In the case where the density of people or the density of heat-generating components in the target space changes significantly within 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, a more matching target cooling demand can be determined based on the initial cooling demand to control the central air conditioner to cool the target space according to the target cooling demand.

[0065] In one embodiment, the initial cooling demand of the target space in the current time period is obtained in the following manner: obtaining the historical cooling demands of the target space in a plurality of 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 the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods.

[0066] The historical cooling demand of the target space in the historical time period before the current time period is the regulation result of the user on the cooling capacity of the central air conditioner in the target space, or the regulation result of the central air conditioner itself on the cooling capacity of the target space; for example, providing a higher cooling capacity for the target space when the target space needs a lower temperature, or providing a lower cooling capacity for the target space when the target space needs a higher temperature.

[0067] In the case where the density of people in the target space does not change significantly within 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, the initial cooling demand of the target space predicted based on the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods has a high probability of also enabling the actual cooling capacity to meet the cooling capacity demand in the current time period.

[0068] In this way, predicting the initial cooling demand of the target space in the current time period based on the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods can better cool the users or the equipment to be cooled in the target space in the current time period.

[0069] In one embodiment, predicting the initial cooling demand of the target space in the current time period based on the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods includes: performing exponential smoothing prediction on the initial cooling demand of the target space in the current time period based on the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods; or performing linear regression prediction on the initial cooling demand of the target space in the current time period based on the plurality of historical cooling demands of the target space in the corresponding plurality of historical time periods.

[0070] Exponential smoothing or linear regression can reflect the changes in the refrigeration demand within a certain period of time. By using the multiple historical refrigeration demands of the target space in corresponding multiple historical time periods, a linear regression prediction or exponential smoothing prediction is performed on the initial refrigeration demand of the target space in the current time period. The obtained prediction result has a high probability of meeting the refrigeration demand of the target space in the current time period.

[0071] In addition to using exponential smoothing prediction or linear regression to predict the initial refrigeration demand of the target space in the current time period, a pre-trained prediction model can also be used to achieve the prediction of the initial refrigeration demand of the target space in the current time period. The prediction model can be obtained by training using the multiple historical refrigeration demands of the target space in corresponding multiple historical time periods.

[0072] In one embodiment, determining the target refrigeration demand for the target space in the next time period of the current time period according to the initial refrigeration demand and the evaluation value corresponding to the current time period includes: , where is the target refrigeration demand for the target space in the next time period of the current time period, is the initial refrigeration demand, is the refrigeration capacity of the central air-conditioning unit for the target space in the current time period, e is the natural constant, and H is the evaluation value corresponding to the current time period.

[0073] Since the refrigeration capacity of the central air-conditioning unit for the target space in the current time period is determined according to the inlet water temperature, return water temperature, and water flow rate of the chilled water in the target space by the central air-conditioning, the chilled water can sense the change in the refrigeration demand of the target space through heat exchange with the air extracted from the target space.

[0074] When the initial refrigeration demand in the current time period is relatively stable compared to the historical refrigeration demand at the previous moment, and the refrigeration capacity of the central air-conditioning unit for the target space in the current time period increases, it indicates that the actual refrigeration demand of the target space in the current time period is increasing. Higher refrigeration capacity can be provided for the target space to adapt to the change in the actual refrigeration demand of the target space.

[0075] H is the evaluation value corresponding to the current time period, which can characterize the degree of difference between the refrigeration capacity of the target space in the current time period and the refrigeration capacities of multiple other time periods before the current time period. The larger the value of H, the greater the change range of the actual demand for the refrigeration capacity of the target space in the current time period; through it can reflect the change direction of the refrigeration capacity of the target space in the current time period. Therefore, the calculation formula for the target refrigeration demand can consider the change direction and change range of the refrigeration capacity demand of the target space in the current time period.

[0076] The greater the change range of the cooling capacity demand of the target space in the current time period, the greater the adjustment amount required for the cooling capacity of the target space; or, the greater the difference between the initial cooling demand of the target space in the current time period determined according to the historical time period and the actual cooling capacity continuously provided by the central air conditioner in the current time period, the greater the influence degree of the change in the density of personnel or heating components in the target space on the cooling demand. Therefore, the greater the adjustment amount required for the cooling capacity of the target space.

[0077] In this way, the target cooling demand for the target space in the next time period of the current time period can be determined according to the cooling capacity, the initial cooling demand, and the evaluation value corresponding to the current time period of the central air conditioner unit for the target space, and the target cooling demand can better meet the cooling demand of the target space in the next time period of the current time period.

[0078] In step S104, according to the target cooling demand for the target space in the next time period, control the central air conditioner unit to cool the target space in the next time period.

[0079] In the embodiment of the present application, the determined target cooling demand for the target space can timely adapt to the change in the personnel density or the weather temperature of the target space. Therefore, controlling the central air conditioner 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 can ensure the stability of the cooling effect of the central air conditioner unit on the target space.

[0080] In one embodiment, controlling the central air conditioner 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, adjusting at least one of the following when the central air conditioner 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 conditioner unit for the target space.

[0081] By adjusting the cooling parameters when the central air conditioner cools the target space, it is possible to adapt to the change in the density of personnel or heating components in the target space, so as to more efficiently achieve the cooling of the target space and avoid over-cooling or under-cooling.

[0082] For example, when the personnel density rises within a short period of time, in order to ensure the cooling effect on the target space, the inlet temperature of the chilled water can be reduced, the water flow rate of the chilled water can be increased, or the cooling air supply volume can be increased.

[0083] In the case where the personnel density decreases within a short period of time, for example, when people leave after a meeting, in order to maintain the stability of the refrigeration effect on the target space and avoid waste of energy, the inlet temperature of the chilled water can be increased, the water flow rate of the chilled water can be decreased, or the refrigeration air supply volume can be decreased.

[0084] In one embodiment, it is also possible to determine the change information of the personnel density in the target space within the current time period based on the image monitoring data of the target space obtained by the image sensor, and control the refrigeration of the central air-conditioning unit for the target space according to the change information.

[0085] For example, at least one image sensor can be arranged in the target space. Based on the image monitoring data obtained by the image sensor, the number of personnel in the target space at different times can be determined to determine the change information of the personnel density in the target space within the current time period; the change information is used to characterize the change situation of the personnel density in the target space.

[0086] Controlling the refrigeration of the central air-conditioning unit for the target space according to the change information may include: when the change information indicates that the personnel density in the target space increases, the refrigeration capacity of the central air-conditioning for the target space can be increased; or, when the change information indicates that the personnel density in the target space decreases, the refrigeration capacity of the central air-conditioning for the target space can be decreased.

[0087] Compared with perceiving the personnel density in the target space through the inlet temperature and return water temperature of the chilled water of the central air-conditioning unit, based on the image monitoring data obtained by the image sensor, the change situation of the personnel density can be detected earlier. Therefore, the refrigeration capacity of the central air-conditioning for the target space can better meet the user's refrigeration experience.

[0088] Figure 2 It is a schematic structural diagram of a control system 1000 of a central air-conditioning unit shown according to an exemplary embodiment. Refer to Figure 2 , the control system 1000 of the central air-conditioning unit includes: a processor 1100 and a memory 1200. The memory 1200 stores computer program instructions, and when the computer program instructions are executed by the processor 1100, all steps or part of the steps of the control method of the central air-conditioning unit in this application are implemented.

[0089] Those skilled in the art will readily think of other implementation schemes of this application after considering the specification and practicing the invention disclosed here. This application is intended to cover any variations, uses, or adaptive changes of this application, and these variations, uses, or adaptive changes follow the general principles of this application and include the common general knowledge or conventional technical means in the technical field not disclosed in this application. The specification and embodiments are only regarded as exemplary.

[0090] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope.

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 an evaluation value of the cooling capacity of the target space by the central air-conditioning unit in the current time period; the evaluation value is used to characterize the degree of 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; 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 according to 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 evaluation value of the cooling capacity of the target space in the current time period is determined in the following way: For a target time period among multiple time periods, construct data points corresponding to the target time period according to 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 is performed on the plurality of second data points to obtain a second average distance between the plurality of clustered clusters after clustering, and the evaluation value is obtained according to a ratio of the first average distance to the second average distance.

3. The control method of the central air conditioning unit according to claim 2, characterized in that: Obtaining the evaluation value according to the ratio of the first average distance to the second average distance includes: Determine the difference between different sub-cooling capacities in different sub-time periods within the current time period, among the cooling capacities of the central air-conditioning unit for the target space in the current time period; The evaluation value is obtained by dividing the ratio of the first average distance to the second average distance by the difference degree value.

4. 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 according to multiple historical cooling demands of the target space in the corresponding multiple historical time periods.

5. The control method of the central air conditioning unit according to claim 4, characterized in that: According to multiple historical cooling demands of the target space in corresponding multiple historical time periods, the initial cooling demand of the target space in the current time period is predicted, including: According to multiple historical cooling demands of the target space in 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, based on a plurality of historical cooling demands of the target space in a plurality of corresponding historical time periods, a linear regression prediction is performed on the initial cooling demand of the target space in the current time period.

6. The control method of the central air conditioning unit according to claim 1, characterized in that: Determining a target cooling demand for a 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.

7. The control method of the central air conditioning unit according to claim 1, characterized in that: According to the target cooling demand for the target space in the next time period, controlling the central air conditioning unit to cool the target space in the next time period includes: According to 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 flow rate of the chilled water and the cooling air supply volume of the central air-conditioning unit to the target space.

8. The control method of the 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 water temperature and the inlet water temperature of the chilled water in the central air conditioning unit; According to 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.

9. 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.

10. 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, a control method for a central air-conditioning unit according to any one of claims 1 to 9 is implemented.

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