A water multi-connection system, its control method and air conditioning

Abstract

This invention discloses a water-cooled multi-split system, its control method, and an air conditioner. The water-cooled multi-split system includes an outdoor unit and an indoor unit. A buffer water tank is installed on the return water pipe of the outdoor unit. It also includes: a chilled water storage tank, whose inlet and outlet pipes are respectively connected to the outlet water pipe of the outdoor unit; a bypass pipe, located between the inlet and outlet pipes of the buffer water tank, for bypassing water in the return water pipe of the outdoor unit; and a controller for controlling whether the chilled water storage tank enters a chilled water storage state based on the outdoor ambient temperature, controlling whether the chilled water storage tank enters a supplementary cooling state or a cooling capacity consumption state based on the load state of the water-cooled multi-split system, and controlling the conduction state of the bypass pipe. Through this invention, insufficient cooling capacity can be provided by the chilled water storage tank to meet the temperature regulation needs of indoor users and improve user comfort.

Description

Technical Field

[0001] This invention relates to the field of heat exchange technology, and more specifically, to a water multi-connection system, its control method, and an air conditioner. Background Technology

[0002] A water-cooled multi-split air conditioning system mainly consists of an outdoor unit connected to multiple indoor units. In cooling mode, the outdoor unit draws chilled water, which is then pumped to each indoor unit. The indoor units then exchange heat with the indoor air, thus lowering the indoor temperature. When configuring the indoor and outdoor unit capacity ratio for a water-cooled multi-split air conditioning system, it is typically chosen between 20% and 200%. For better economic efficiency, the total capacity of the indoor units is usually greater than the rated capacity of the outdoor units. In summer, the indoor heat load is lower in the morning and evening, but higher at midday. If many indoor units are running simultaneously, the cooling demand of the indoor units may exceed the rated cooling capacity of the outdoor units, affecting the temperature regulation of the indoor units and resulting in lower indoor comfort.

[0003] There is currently no effective solution to the problem that when the cooling demand of the indoor unit exceeds the rated cooling capacity of the outdoor unit, it affects the temperature regulation of the indoor unit and leads to lower comfort for indoor occupants. Summary of the Invention

[0004] This invention provides a water-cooled multi-split system, its control method, and an air conditioner to solve the problem in the prior art where the indoor unit's cooling demand exceeds the outdoor unit's rated cooling capacity, affecting the indoor unit's temperature regulation and resulting in lower comfort levels for indoor occupants.

[0005] To solve the above-mentioned technical problems, the present invention provides a multi-split water system, which includes an outdoor unit and an indoor unit, wherein a buffer water tank is installed on the return water pipe of the outdoor unit. The multi-split water system includes: The cold water storage tank has its inlet pipe connected to the outlet pipe of the outdoor unit. A bypass pipe is installed between the inlet pipe and the outlet pipe of the buffer water tank to bypass the water in the return pipe of the outdoor unit. The controller is used to control whether the cold storage tank enters the cold storage state according to the outdoor ambient temperature, to control whether the cold storage tank enters the supplemental cooling state or the cold energy consumption state according to the load state of the water multi-connection system, and to control the conduction state of the bypass pipeline.

[0006] Furthermore, the water multi-connection system also includes: The first valve has its inlet connected to the water outlet pipe of the outdoor unit, its first outlet connected to the water inlet pipe of the cold water storage tank, and its second outlet connected to the first inlet of the second valve. The second valve has its second inlet connected to the outlet pipe of the cold water storage tank, and its outlet connected to the inlet pipe of the indoor unit and the inlet pipe of the floor heating equipment.

[0007] Furthermore, the water multi-connection system also includes: The third valve is installed on the outlet pipe of the buffer water tank; The fourth valve is installed on the inlet pipe of the buffer water tank; The fifth valve is located on the bypass pipeline.

[0008] Furthermore, the water multi-connection system also includes: A pressure balancing pipeline is installed between the cold water storage tank and the buffer tank, with its first end connected to the upper part of the cold water storage tank and its second end connected to the upper part of the cold water storage tank.

[0009] Furthermore, the water multi-connection system also includes: A cooling water pump is installed on the outlet pipe of the cooling water tank.

[0010] The present invention also provides a control method applied to the above-mentioned multi-system water system, the method comprising: The cold storage tank is controlled to enter the cold storage state based on the outdoor ambient temperature. After the cold storage tank has completed its cold storage, the cold storage tank is controlled to enter either a supplemental cooling state or a cold energy consumption state according to the load status of the water multi-connection system.

[0011] Furthermore, the system controls whether the chilled water tank enters the chilled water storage state based on the outdoor ambient temperature, including: After the operation cycle of the water multi-connection system begins, the outdoor ambient temperature is acquired once at preset intervals. Determine whether the rate of change of the outdoor ambient temperature is greater than zero; If so, the cold water storage tank is controlled to enter the cold storage state.

[0012] Furthermore, before controlling the cold water tank to enter the cold storage state, the method further includes: Obtain the historical operating data of the water multi-connection system; The total duration of overload operation of the water multi-system in the previous operating cycle is determined based on the historical operating data. The required chilled water capacity of the cold water storage tank is calculated based on the total duration of overload operation.

[0013] Furthermore, after calculating the required chilled water capacity of the cold water storage tank based on the total duration of the overload operation, the method further includes: Determine the current weather conditions based on the outdoor ambient temperature; The correction factor for the required chilled water capacity is determined based on the current weather conditions. The required chilled water capacity is adjusted according to the correction factor.

[0014] Furthermore, judging the current weather conditions based on the outdoor ambient temperature includes: Determine the trend of outdoor ambient temperature change before the rate of change of outdoor ambient temperature exceeds zero. If the rate of change of the outdoor ambient temperature is greater than that before zero time, and the outdoor ambient temperature gradually decreases, then the current weather is determined to be sunny. If the rate of change of the outdoor ambient temperature is greater than before the zero moment, and the outdoor ambient temperature remains unchanged, then continue to acquire the trend of change of the outdoor ambient temperature within a preset time after the rate of change of the outdoor ambient temperature is greater than the zero moment. If the rate of change of the outdoor ambient temperature is greater than the trend of gradual increase within a preset time after the zero moment, then the current weather is determined to be cloudy. If the rate of change of the outdoor ambient temperature is greater than the trend of change within a preset time after the zero moment remains unchanged, then the current weather is determined to be a cloudy or rainy day.

[0015] Furthermore, a correction factor for the chilled water demand capacity is determined based on the current weather conditions, including: If the current weather is sunny, then the correction factor is determined to be K1; If the current weather is cloudy, then the correction factor is determined to be K2; If the current weather is cloudy and rainy, then the correction factor is determined to be K3; Among them, K1 > K2 > K3.

[0016] Furthermore, when correcting the chilled water demand capacity according to the correction factor, the following formula is used: = *Kn; in, For the revised chilled water demand capacity, Kn is the required chilled water capacity, and Kn is a correction factor, n = 1, 2, 3.

[0017] Furthermore, controlling the cold water storage tank to enter the cold storage state includes: The inlet, outlet, and outlet of the first valve are all open; the inlet and outlet of the second valve are open, and the inlet is closed; the third and fifth valves are open, and the fourth valve is closed. The first valve has its inlet connected to the outlet pipe of the outdoor unit, its first outlet connected to the inlet pipe of the cold water storage tank, and its second outlet connected to the first inlet of the second valve; the second valve has its second inlet connected to the outlet pipe of the cold water storage tank, and its outlet connected to the inlet pipe of the indoor unit; the third valve is located on the outlet pipe of the buffer water tank; the fourth valve is located on the inlet pipe of the buffer water tank; and the fifth valve is located on a bypass pipe, which is located between the inlet pipe and the outlet pipe of the buffer water tank.

[0018] Furthermore, controlling the chilled water tank to enter either a supplemental cooling state or a cooling capacity consumption state based on the load status of the water multi-connection system includes: Determine whether the load status of the water multi-connection system is overloaded; If so, the cold water storage tank is controlled to enter the cooling replenishment state; After controlling the cold water tank to enter the cooling replenishment state, determine whether the load state of the water multi-connection system has switched to low load; If so, the cold water storage tank is controlled to enter a state of cold energy consumption.

[0019] Furthermore, controlling the cold water storage tank to enter the cooling replenishment state includes: Control the inlet and second outlet of the first valve to be open; control the first inlet, second inlet and outlet of the second valve to be open; control the fourth and fifth valves to be open, and the third valve to be closed; control the cooling water pump to be turned on; The cooling water pump is installed on the outlet pipe of the cooling water tank.

[0020] Furthermore, after controlling the cold water storage tank to enter the replenishment cooling state, the method further includes: Control the speed of the make-up water pump so that the sum of the make-up water pump's flow rate and the outdoor unit's maximum water flow rate equals the sum of the indoor unit's required water flow rate.

[0021] Furthermore, controlling the cold water storage tank to enter a state of cold energy consumption includes: The system controls the first valve inlet, first outlet, and second outlet to be closed; controls the second valve inlet and outlet to be open; controls the third and fifth valves to be closed and the fourth valve to be open; controls the cooling water pump to be turned on, and simultaneously controls the outdoor unit to be turned off.

[0022] Furthermore, after controlling the cold water storage tank to enter a cooling replenishment state, or controlling the cold water storage tank to enter a cooling consumption state, the method further includes: Determine whether the water level in the cold water storage tank has reached the minimum water level; If so, the cold water storage tank will stop supplying cooling, and the outdoor unit will supply cooling independently.

[0023] Furthermore, controlling the cold water storage tank to stop supplying cooling and controlling the outdoor unit to supply cooling independently includes: Control the inlet and second outlet of the first valve to be open, and close the first outlet; control the first inlet and outlet of the second valve to be open, and close the second inlet; control the third and fourth valves to be open, and close the fifth valve; control the cooling water pump to be closed.

[0024] The present invention also provides an air conditioner, including the above-described water multi-split system, and applying the above-described control method.

[0025] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the above-described control method.

[0026] By applying the technical solution of this invention, a cold water storage tank is installed on the outlet pipe of the outdoor unit. When the outdoor ambient temperature begins to rise, the cold water storage tank is controlled to start storing cold energy. Then, according to the load status of the water multi-split system, the cold water storage tank is controlled to supply cooling to the indoor unit alone or to supply cooling to the indoor unit together with the outdoor unit. At the same time, the circulating water volume in the water multi-split system is kept constant through the buffer water tank and bypass pipe. This enables the cold water storage tank to provide the insufficient cooling energy when the cooling demand of the indoor unit is greater than the rated cooling capacity of the outdoor unit, thereby meeting the temperature regulation needs of indoor users and improving user comfort. Attached Figure Description

[0027] Figure 1 For existing water multi-connection systems; Figure 2 This is a structural diagram of a water multi-connection system according to an embodiment of the present invention; Figure 3 A flowchart of a control method according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the water flow direction under the cold storage state according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the water flow direction under the supplemental cooling state according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the water flow direction under the cooling capacity consumption state according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the water flow direction under the independent cooling state of the outdoor unit according to an embodiment of the present invention; Figure 8 This is a flowchart of a control method according to another embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0029] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0030] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0031] It should be understood that although the terms first, second, third, etc., may be used to describe valves in the embodiments of the present invention, these valves should not be limited to these terms. These terms are only used to distinguish valves. For example, without departing from the scope of the embodiments of the present invention, a first valve may also be referred to as a second valve, and similarly, a second valve may also be referred to as a first valve.

[0032] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0033] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0034] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0035] Example 1 Figure 1 The existing water-cooled multi-split system includes an outdoor unit 10, an indoor unit 20, and a water pump 101. A buffer tank is installed on the return water pipe of the outdoor unit 10. In summer, the indoor heat load is lower in the morning and evening, but higher at midday. If multiple indoor units 20 are running simultaneously, the cooling demand of the indoor units 20 may exceed the rated cooling capacity of the outdoor units, affecting the temperature regulation of the indoor units and resulting in lower comfort levels for occupants. Although the existing water-cooled multi-split system includes a buffer tank, the buffer tank only ensures a constant water volume in the heat exchange system and cannot provide cooling; therefore, it cannot supplement insufficient cooling capacity.

[0036] To address the aforementioned technical problems, this embodiment provides a multi-system water supply system. Figure 2 A structural diagram of a water multi-connection system according to an embodiment of the present invention is shown below. Figure 2 As shown, based on existing technology, this water multi-connection system also includes: The cold water storage tank 40 has its inlet pipe connected to the outlet pipe of the outdoor unit 10.

[0037] Bypass pipe 301 is installed between the inlet pipe and the outlet pipe of the buffer water tank and is used to bypass the water in the return pipe of the outdoor unit 10.

[0038] The controller (not shown in the figure) is used to control whether the cold storage tank 40 enters the cold storage state according to the outdoor ambient temperature, to control whether the cold storage tank 40 enters the supplemental cooling state or the cold energy consumption state according to the load state of the water multi-connection system, and to control the conduction state of the bypass pipeline 301.

[0039] In actual operation, after the start of the operating cycle (e.g., one day) of the water-cooled multi-split system, the outdoor ambient temperature is acquired at preset intervals. For example, if the operating cycle of the water-cooled multi-split system is one day, the outdoor ambient temperature is acquired starting at midnight. The system then checks if the rate of change of the outdoor ambient temperature is greater than zero. If it is, it indicates that the outdoor ambient temperature is starting to rise. At this time, the cooling capacity of the outdoor unit 10 also accumulates to its maximum value, and the chilled water tank 40 is controlled to enter the cooling storage state. After the chilled water tank 40 completes cooling storage, the load status of the water-cooled multi-split system is determined. If the load status of the water-cooled multi-split system is overloaded, the chilled water tank 40 is controlled to enter the cooling replenishment state, meaning that the outdoor unit 10 and the chilled water tank 40 jointly supply cooling to the indoor unit 20. If the load status of the water-cooled multi-split system is low after the chilled water tank 40 enters the cooling replenishment state, the chilled water tank 40 is controlled to enter the cooling consumption state, meaning that the chilled water tank 40 supplies cooling to the indoor unit 20 alone. Overload operation refers to the sum of the cooling demand of indoor units 20 being higher than or equal to 95% of the rated cooling capacity of outdoor unit 10, while low load operation refers to the sum of the cooling demand of indoor units 20 being lower than 95% of the rated cooling capacity of outdoor unit 10.

[0040] In this embodiment of the water-cooled multi-split system, a chilled water tank 40 is installed on the outlet pipe of the outdoor unit 10. When the outdoor ambient temperature begins to rise, the chilled water tank 40 is controlled to start storing cold energy. Then, according to the load status of the water-cooled multi-split system, the chilled water tank 40 is controlled to supply cooling to the indoor unit 20 alone, or the chilled water tank 40 and the outdoor unit 10 jointly supply cooling to the indoor unit 20. At the same time, the circulating water volume in the water-cooled multi-split system is kept constant through the buffer water tank and the bypass pipe 301. This enables the chilled water tank 40 to provide the insufficient cooling energy when the cooling demand of the indoor unit 20 exceeds the rated cooling capacity of the outdoor unit, thereby meeting the temperature regulation needs of indoor users and improving user comfort.

[0041] like Figure 2 As shown, in order to control the state of the cold water storage tank 40 to switch between cold storage, cold replenishment and cold energy consumption states, the water multi-split system also includes: a first valve 401, which is a three-way valve with one inlet and two outlets. Its inlet is connected to the water outlet pipe of the outdoor unit 10, its first outlet is connected to the water inlet pipe of the cold water storage tank 40, and its second outlet is connected to the first inlet of the second valve 402; and a second valve 402, which is also a three-way valve with two inlets and one outlet. Its second inlet is connected to the water outlet pipe of the cold water storage tank 40, and its outlet is connected to the water inlet pipe of the indoor unit 20 and the water inlet pipe of the underfloor heating equipment.

[0042] In order to control the opening and closing of the bypass pipe 301 to ensure a constant circulating water volume, the above-mentioned water multi-connection system also includes: a third valve 303, which is installed on the outlet pipe of the buffer water tank; a fourth valve 304, which is installed on the inlet pipe of the buffer water tank; and a fifth valve 305, which is installed on the bypass pipe 301.

[0043] To avoid pressure imbalance between the cold storage tank 40 and the buffer tank, which could lead to excessively high or low pressure in the tanks, the aforementioned multi-unit water system further includes a pressure balancing pipeline 302, which is installed between the cold storage tank 40 and the buffer tank. Its first end is connected to the upper part of the cold storage tank 40, and its second end is also connected to the upper part of the cold storage tank 40. This pipeline is used to ensure pressure balance between the cold storage tank 40 and the buffer tank and improve the stability of the heat exchange system.

[0044] In order to drive the chilled water in the cold water storage tank 40 to flow out, the water multi-connection system also includes: a makeup water pump 403, which is installed on the outlet pipe of the cold water storage tank 40, and the speed of the makeup water pump 403 is adjustable.

[0045] Example 2 This embodiment provides a control method applied to the water multi-connection system described in the above embodiment. Figure 3 A flowchart of a control method according to an embodiment of the present invention is shown below. Figure 3 As shown, the control method includes: S101 controls whether the cold water storage tank enters the cold storage state based on the outdoor ambient temperature.

[0046] S102, after the cold storage tank has completed cold storage, the cold storage tank is controlled to enter either the replenishment state or the cold energy consumption state according to the load status of the water multi-connection system.

[0047] The cooling replenishment state refers to the cold water storage tank 40 and the outdoor unit 10 jointly supplying cooling for the indoor unit 20, while the cooling capacity consumption state refers to the cold water storage tank 40 supplying cooling for the indoor unit 20 alone.

[0048] The control method of this embodiment controls whether the cold storage tank 40 enters the cold storage state according to the outdoor ambient temperature, so as to store cold in the cold storage tank 40 when the cold capacity of the outdoor unit 10 is at its maximum. After the cold storage tank 40 completes the cold storage, the load status of the water multi-split system is judged. The cold storage tank 40 is controlled to enter the supplemental cooling state or the cold capacity consumption state according to the load status of the water multi-split system, which can maximize the supply of cold capacity to the indoor unit 20, meet the temperature regulation needs of indoor users, and improve user comfort.

[0049] As mentioned earlier, when the outdoor ambient temperature begins to rise, the cooling capacity of the outdoor unit 10 accumulates to its maximum value. At this time, the chilled water tank 40 is controlled to enter the chilled water storage state to ensure sufficient cooling capacity. Therefore, the control of whether the chilled water tank 40 enters the chilled water storage state based on the outdoor ambient temperature includes: after the start of the operation cycle of the water multi-split system, acquiring the outdoor ambient temperature once at a preset interval; determining whether the rate of change of the outdoor ambient temperature is greater than zero; if so, controlling the chilled water tank 40 to enter the chilled water storage state.

[0050] Taking a water multi-split system with an operating cycle of 1 day as an example, starting from 0:00, outdoor unit 10 records the outdoor ambient temperature value every 10 minutes. , , … In its first appearance At that time, When the first valve 401 is adjusted to a three-way valve, the water flow ratio of the first outlet and the second outlet is adjusted at the same time. While ensuring the cooling of the indoor unit 20, the chilled water is controlled to start entering the cold water storage tank 40 for cold storage.

[0051] To accurately control the chilled water storage capacity of the chilled water tank 40, historical operating data of the heat exchange system can be referenced. The chilled water demand capacity of the chilled water tank 40 can be calculated based on the total overload operation time in the previous operating cycle. That is, before the chilled water tank 40 enters the chilled water storage state, the above method also includes: obtaining historical operating data of the water multi-split system; determining the total overload operation time of the water multi-split system in the previous operating cycle based on the historical operating data; and calculating the chilled water demand capacity of the chilled water tank 40 based on the total overload operation time.

[0052] Assuming the operating cycle of the above-mentioned multi-split water system is one day, record the operating time of the multi-split water outdoor unit during the 0-24 hour period of the previous day. The system detects the operating mode and speed of each indoor unit 20, and calculates the sum of the required cooling capacity of each indoor unit 20 based on the preset rated cooling capacity and rated water flow rate of each speed. The sum of the water flow requirements of the indoor unit 20 .

[0053] like ≥ *95% ( (This refers to the rated cooling capacity of the multi-split outdoor unit), which is recorded as the multi-split outdoor unit operating at overcapacity. The duration of this overcapacity operation is also recorded. According to ( Calculate the required chilled water capacity to be added to the multi-split water system during the period when the outdoor unit 10 is operating at overcapacity (based on the maximum water flow rate that outdoor unit 10 can provide). .

[0054] Figure 4 This is a schematic diagram of the water flow direction under the cold storage state according to an embodiment of the present invention, such as... Figure 4 As shown, after calculating the required chilled water capacity, the inlet, first outlet, and second outlet of the first valve 401 are all open; the first inlet and outlet of the second valve 402 are open, and the second inlet is closed; since the outdoor unit 10 supplies water to the chilled water storage tank 40, this operation will reduce the circulating water volume of the heat exchange system. In order to ensure that the circulating water volume remains unchanged, water needs to be replenished from the buffer tank. Therefore, the third valve 303 and the fifth valve 305 are open, and the fourth valve 304 is closed, so that the water flowing back to the outdoor unit 10 flows through the bypass pipe 301, and the buffer tank replenishes water to the heat exchange system through the outlet pipe; and the chilled water storage tank 40 is controlled to store chilled water according to the required chilled water capacity.

[0055] As mentioned above Figure 2 As shown, the inlet of the first valve 401 is connected to the outlet pipe of the outdoor unit 10, the first outlet is connected to the inlet pipe of the cold water storage tank 40, and the second outlet is connected to the first inlet of the second valve 402; the second inlet of the second valve 402 is connected to the outlet pipe of the cold water storage tank 40, and the outlet is connected to the inlet pipe of the indoor unit 20; the third valve 303 is installed on the outlet pipe of the buffer water tank; the fourth valve 304 is installed on the inlet pipe of the buffer water tank; and the fifth valve 305 is installed on the bypass pipe 301, which is located between the inlet pipe and the outlet pipe of the buffer water tank.

[0056] The cooling capacity required by the indoor unit 20 varies under different weather conditions. For example, on a sunny day, the outdoor temperature is high, and the cooling capacity required by the indoor unit 20 is high. On a cloudy or rainy day, the outdoor temperature is low, and the cooling capacity required by the indoor unit 20 is also low. Therefore, after calculating the chilled water demand capacity of the chilled water storage tank 40 based on the total overload operation time, the method also includes: judging the current weather conditions based on the outdoor temperature; determining the correction factor for the chilled water demand capacity based on the current weather conditions; and correcting the chilled water demand capacity based on the correction factor.

[0057] On sunny days, starting from 0h, the outdoor temperature gradually decreases, reaching its lowest point when the sun rises in the morning, and then begins to rise until 12h. On cloudy days, starting from 0h, the outdoor temperature remains relatively stable, rising as the sun rises or is delayed until 12h. On overcast or rainy days, starting from 0h, the outdoor temperature remains relatively stable, especially in the morning, until 12h. Therefore, judging the current weather conditions based on the outdoor temperature specifically includes: determining if the rate of change of the outdoor temperature is greater than zero time. The weather forecast is as follows: If the rate of change of outdoor ambient temperature is greater than before zero time and the outdoor ambient temperature gradually decreases, the current weather is determined to be sunny; if the rate of change of outdoor ambient temperature is greater than before zero time and the outdoor ambient temperature remains unchanged, the forecast continues to acquire the trend of outdoor ambient temperature change within a preset time period after the rate of change of outdoor ambient temperature exceeds zero time; if the trend of outdoor ambient temperature change within the preset time period after the rate of change of outdoor ambient temperature exceeds zero time is gradually increasing, the current weather is determined to be cloudy; if the trend of outdoor ambient temperature change within the preset time period after the rate of change of outdoor ambient temperature exceeds zero time is unchanged, the current weather is determined to be overcast and rainy.

[0058] For example, from 0h until the first occurrence During the time period, like ≤ < If the weather is sunny, then today's weather is determined to be sunny. like = = If the weather is cloudy or rainy, then we can determine that today's weather is cloudy or rainy, and continue to determine the trend of temperature after it starts to rise. After the temperature begins to rise, if ≤ < If so, then today's weather is determined to be cloudy; After the temperature begins to rise, if = = If so, then today's weather is determined to be cloudy and rainy.

[0059] Where n represents the number of tests, This represents the outdoor ambient temperature detected for the nth time. Indicates the nth The outdoor ambient temperature detected in one instance. This represents the outdoor ambient temperature detected for the (n+1)th time, and so on.

[0060] Outdoor weather conditions can be determined not only by detecting temperature changes at different times, but also by plotting outdoor temperature change curves in real time. Even better, if possible, the device can be directly connected to the local weather forecast system to obtain more accurate weather information.

[0061] As mentioned earlier, on sunny days, the outdoor temperature is higher, and the cooling capacity required by the indoor unit 20 is higher. On cloudy or rainy days, the outdoor temperature is lower, and the cooling capacity required by the indoor unit 20 is also lower. Therefore, the correction factor for the chilled water demand capacity is determined based on the current weather conditions, including: if the current weather is sunny, the correction factor is K1; if the current weather is cloudy, the correction factor is K2; if the current weather is rainy, the correction factor is K3; where K1 > K2 > K3.

[0062] When adjusting the chilled water demand capacity based on the correction factor, the following formula is used: = *Kn; in, For the revised chilled water demand capacity, Kn is the required chilled water capacity, and Kn is a correction factor, n = 1, 2, 3.

[0063] For example, if the weather is sunny, Kn = 1.1; if the weather is cloudy, Kn = 1; if the weather is overcast and rainy, Kn = 0.8.

[0064] At the same time, the required chilled water storage capacity will be adjusted to the required chilled water demand. With the rated volume of the cold water storage tank 40 To make a comparison, if ≥ Then, based on the rated volume of the cold water storage tank of 40... After the cold storage of the water-cooled multi-unit system is completed, determine whether the cold storage tank 40 should start supplemental cooling based on the load of the heat exchange system.

[0065] When a multi-split water system is overloaded, the chilled water tank 40 needs to replenish the insufficient cooling capacity. After the chilled water tank 40 replenishes the cooling capacity, the overload status of the multi-split water system may be alleviated or changed. At this time, if there is still excess chilled water in the chilled water tank 40, this part of the chilled water can be consumed first to empty the chilled water tank 40. Therefore, the chilled water tank 40 is controlled to enter either the cooling replenishment state or the cooling capacity consumption state according to the load status of the multi-split water system, including: determining whether the load status of the multi-split water system is overloaded; if yes, controlling the chilled water tank 40 to enter the cooling replenishment state; if no, controlling the multi-split water system to operate normally; after controlling the chilled water tank 40 to enter the cooling replenishment state, determining whether the load status of the multi-split water system switches to low load; if yes, controlling the chilled water tank 40 to enter the cooling capacity consumption state; if no, controlling the chilled water tank 40 to remain in the cooling replenishment state.

[0066] Figure 5 This is a schematic diagram of the water flow direction under the supplemental cooling state according to an embodiment of the present invention, such as... Figure 5 As shown, controlling the cold water storage tank 40 to enter the cooling replenishment state includes: controlling the inlet and second outlet of the first valve 401 to be open; controlling the first inlet, second inlet and outlet of the second valve 402 to be open; since the cold water storage tank 40 replenishes water to the heat exchange system in the cooling replenishment state, in order to ensure that the circulating water volume of the heat exchange system remains unchanged, controlling the fourth valve 304 and the fifth valve 305 to be open, and the third valve 303 to be closed, so that the water flowing out of the indoor unit 20 returns to the return water pipe of the outdoor unit 10, and the excess water enters the buffer water tank; at the same time, controlling the cooling water pump 403 to be turned on; wherein, the cooling water pump 403 is installed on the outlet water pipe of the cold water storage tank 40.

[0067] In order to ensure that the cooling capacity replenished by the cold storage tank 40 is equal to the cooling capacity missing by the heat exchange system, and to avoid excessive or insufficient cooling capacity, after the cold storage tank 40 enters the cooling replenishment state, the method also includes: controlling the speed of the cooling water pump 403 so that the sum of the water flow rate of the cooling water pump 403 and the maximum water flow rate of the outdoor unit 10 is equal to the sum of the required water flow rate of the indoor unit 20.

[0068] For example, after the cold storage is completed, the sum of the cooling capacity required by the indoor unit 20 is calculated in real time. The sum of the water flow requirements of the indoor unit 20 .like ≥ *95% indicates that the water-cooled multi-split system has entered overcapacity operation. The water-cooled multi-split system operates in supplemental cooling mode, based on the sum of the required water flow of indoor unit 20 and the maximum water flow of outdoor unit 10. The difference in speed is adjusted to make the cooling water pump 403 rotate faster. + = ,in, To supplement the water flow rate of cooling water pump 403.

[0069] After the outdoor unit 10 and the chilled water tank 40 are used for combined cooling in the water-cooled multi-split system, if the following occurs: < *95% indicates that the heat exchange system has entered a low-load operation state, and the cold storage water tank 40 is controlled to enter a cold energy consumption state.

[0070] Figure 6 This is a schematic diagram of the water flow direction under the cooling capacity consumption state according to an embodiment of the present invention, such as... Figure 6 The system controls the first valve 401 to close its inlet, first outlet, and second outlet; it controls the second valve 402 to open its second inlet and outlet; since the cold water storage tank 40 replenishes water to the heat exchange system under the condition of cold energy consumption and the outlet and return water pipes of the indoor unit 20 are closed, in order to ensure that the circulating water volume of the heat exchange system remains unchanged, the system controls the third valve 303 and the fifth valve 305 to close and the fourth valve 304 to open, so that the water flowing out of the indoor unit 20 enters the buffer water tank; at the same time, the system controls the cold water pump 403 to start and controls the outdoor unit to shut down.

[0071] Regardless of whether it's in a cooling replenishment state or a cooling capacity consumption state, if the water level in the chilled water storage tank 40 reaches the minimum level, it indicates that the chilled water storage tank 40 can no longer provide cooling. Therefore, it's necessary to control the chilled water storage tank 40 to stop providing cooling and control the outdoor unit 10 to provide cooling independently. Therefore, after controlling the chilled water storage tank 40 to enter either a cooling replenishment state or a cooling capacity consumption state, the method further includes: determining whether the water level in the chilled water storage tank 40 has reached the minimum level; if so, controlling the chilled water storage tank 40 to stop providing cooling and controlling the outdoor unit 10 to provide cooling independently; if not, controlling the chilled water storage tank 40 to remain in either a cooling replenishment state or a cooling capacity consumption state.

[0072] Figure 7 This is a schematic diagram of the water flow direction under the independent cooling state of the outdoor unit according to an embodiment of the present invention, such as... Figure 7 As shown, controlling the cold storage water tank 40 to stop supplying cooling and controlling the outdoor unit 10 to supply cooling alone includes: controlling the inlet and the second outlet of the first valve 401 to be open, and the first outlet to be closed; controlling the first inlet and the outlet of the second valve 402 to be open, and the second inlet to be closed; controlling the third valve 303 and the fourth valve 304 to be open, and the fifth valve 305 to be closed; and controlling the make-up cooling water pump 403 to be closed.

[0073] Example 3 This embodiment provides another control method applied to the water multi-system described in the above embodiment. Figure 8 A flowchart of a control method according to another embodiment of the present invention is shown below. Figure 8 As shown, the method includes: S1 calculates the chilled water demand of the cold storage tank based on the duration of overload operation in the previous day, and adjusts the chilled water demand according to the weather conditions.

[0074] If it is a sunny day, the outdoor temperature is high, and the cooling capacity required by the indoor unit is high. If it is a cloudy or rainy day, the outdoor temperature is low, and the cooling capacity required by the indoor unit is also low. Therefore, the correction factor for the chilled water demand capacity is determined according to the current weather conditions, including: if the current weather is sunny, the correction factor is determined to be K1; if the current weather is cloudy, the correction factor is determined to be K2; if the current weather is rainy, the correction factor is determined to be K3; wherein, K1 > K2 > K3.

[0075] When correcting the chilled water demand capacity according to the correction factor, the following formula is used: = *Kn; in, For the revised chilled water demand capacity, Kn is the required chilled water capacity, and Kn is a correction factor, n = 1, 2, 3.

[0076] For example, if the weather is sunny, Kn = 1.1; if the weather is cloudy, Kn = 1; if the weather is overcast and rainy, Kn = 0.8.

[0077] S2 monitors the outdoor ambient temperature after the start of the water multi-connection system's operating cycle.

[0078] Taking a multi-split water system with a daily operating cycle as an example, starting from 0:00, the outdoor unit records the outdoor ambient temperature value every 10 minutes. , , … .

[0079] S3 controls the cold water storage tank to start storing cold water when the outdoor ambient temperature begins to rise.

[0080] First appearance At that time, When the first valve is adjusted to a three-way valve, the water flow ratio between the first outlet and the second outlet is adjusted to ensure that the indoor unit is refrigerated while controlling the chilled water to start entering the cold storage tank for cold storage.

[0081] S4, after confirming that the water multi-system is overloaded, controls the cold storage tank to start replenishing cooling.

[0082] To ensure that the cooling capacity replenished by the cold storage tank is equal to the cooling capacity missing by the heat exchange system, and to avoid excessive or insufficient cooling capacity, after the cold storage tank enters the cooling replenishment state, the method further includes: controlling the speed of the cooling replenishment pump so that the sum of the water flow rate of the cooling replenishment pump and the maximum water flow rate of the outdoor unit is equal to the sum of the required water flow rate of the indoor unit.

[0083] For example, after the cooling storage is completed, the sum of the cooling capacity required by the indoor units is calculated in real time. The sum of the water flow required by the indoor unit .like ≥ A reading of *95% indicates that the water-cooled multi-split system has entered overcapacity operation. The system operates in supplemental cooling mode, based on the sum of the water flow demands of the indoor units. Maximum water flow rate of outdoor unit The difference in speed is adjusted to control the speed of the make-up cooling water pump. + = ,in, To supplement the cooling water pump's water flow rate.

[0084] S5, after determining that the water multi-system is operating at low load, controls the cold storage tank to start consuming cooling capacity.

[0085] After the outdoor unit and the chilled water tank are used for combined cooling in a multi-split water system, if the following occurs: < *95% indicates that the heat exchange system has entered a low-load operation state, and the control cold storage water tank will enter a state of cold energy consumption.

[0086] Regardless of whether it's in a cooling replenishment state or a cooling capacity consumption state, if the water level in the chilled water tank reaches the minimum level, it indicates that the chilled water tank can no longer provide cooling. Therefore, it's necessary to control the chilled water tank to stop providing cooling and control the outdoor unit to provide cooling independently. Thus, after controlling the chilled water tank to enter either a cooling replenishment state or a cooling capacity consumption state, it's also necessary to determine whether the water level in the chilled water tank has reached the minimum level. If so, control the chilled water tank to stop providing cooling and control the outdoor unit to provide cooling independently; if not, control the chilled water tank to remain in either a cooling replenishment state or a cooling capacity consumption state.

[0087] Example 4 This embodiment provides an air conditioner, including the water multi-split system of the above embodiment, and also applies the control method of the above embodiment to maximize the cooling capacity supply of the indoor unit, meet the temperature regulation needs of indoor users, and improve user comfort.

[0088] Example 5 This embodiment provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the control method of the above embodiment.

[0089] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method for a multi-system water system, characterized in that, The method is applied to a multi-split water system, which includes an outdoor unit, an indoor unit, a chilled water tank, and a bypass pipeline. A buffer tank is installed on the return water pipeline of the outdoor unit. The inlet and outlet pipelines of the chilled water tank are respectively connected to the outlet pipeline of the outdoor unit. The bypass pipeline is located between the inlet and outlet pipelines of the buffer tank and is used to bypass the water in the return water pipeline of the outdoor unit. The cold storage tank is controlled to enter the cold storage state based on the outdoor ambient temperature. After the cold storage tank completes its cold storage, it is controlled to enter either a supplemental cooling state or a cold energy consumption state according to the load status of the water multi-system. The system controls whether the chilled water tank enters the chilled water storage state based on the outdoor ambient temperature, including: After the operation cycle of the water multi-connection system begins, the outdoor ambient temperature is acquired once at preset intervals. Determine whether the rate of change of the outdoor ambient temperature is greater than zero; If so, the cold water storage tank is controlled to enter the cold storage state.

2. The method according to claim 1, characterized in that, Before controlling the cold water tank to enter the cold storage state, the method further includes: Obtain the historical operating data of the water multi-connection system; The total duration of overload operation of the water multi-system in the previous operating cycle is determined based on the historical operating data. The required chilled water capacity of the cold water storage tank is calculated based on the total duration of overload operation.

3. The method according to claim 2, characterized in that, After calculating the required chilled water capacity of the cold water storage tank based on the total duration of overload operation, the method further includes: Determine the current weather conditions based on the outdoor ambient temperature; The correction factor for the required chilled water capacity is determined based on the current weather conditions. The required chilled water capacity is adjusted according to the correction factor.

4. The method according to claim 3, characterized in that, Determine the current weather conditions based on the outdoor ambient temperature, including: Determine the trend of outdoor ambient temperature change before the rate of change of outdoor ambient temperature exceeds zero. If the rate of change of the outdoor ambient temperature is greater than that before zero time, and the outdoor ambient temperature gradually decreases, then the current weather is determined to be sunny. If the rate of change of the outdoor ambient temperature is greater than before the zero moment, and the outdoor ambient temperature remains unchanged, then continue to acquire the trend of change of the outdoor ambient temperature within a preset time after the rate of change of the outdoor ambient temperature is greater than the zero moment. If the rate of change of the outdoor ambient temperature is greater than the trend of gradual increase within a preset time after the zero moment, then the current weather is determined to be cloudy. If the rate of change of the outdoor ambient temperature is greater than the trend of change within a preset time after the zero moment remains unchanged, then the current weather is determined to be a cloudy or rainy day.

5. The method according to claim 3, characterized in that, The correction factor for the required chilled water capacity is determined based on the current weather conditions, including: If the current weather is sunny, then the correction factor is determined to be K1; If the current weather is cloudy, then the correction factor is determined to be K2; If the current weather is cloudy and rainy, then the correction factor is determined to be K3; Among them, K1 > K2 > K3.

6. The method according to claim 3, characterized in that, When correcting the chilled water demand capacity according to the correction factor, the following formula is used: = *Kn; in, For the revised chilled water demand capacity, Kn is the required chilled water capacity, and Kn is a correction factor, n = 1, 2, 3.

7. The method according to claim 1, characterized in that, Controlling the cold water storage tank to enter the cold storage state includes: The inlet, outlet, and outlet of the first valve are all open; the inlet and outlet of the second valve are open, and the inlet is closed; the third and fifth valves are open, and the fourth valve is closed. The first valve has its inlet connected to the outlet pipe of the outdoor unit, its first outlet connected to the inlet pipe of the cold water storage tank, and its second outlet connected to the first inlet of the second valve; the second valve has its second inlet connected to the outlet pipe of the cold water storage tank, and its outlet connected to the inlet pipe of the indoor unit; the third valve is located on the outlet pipe of the buffer water tank; the fourth valve is located on the inlet pipe of the buffer water tank; and the fifth valve is located on a bypass pipe, which is located between the inlet pipe and the outlet pipe of the buffer water tank.

8. The method according to claim 1, characterized in that, Controlling the chilled water tank to enter either a cooling replenishment state or a cooling consumption state based on the load status of the water multi-system includes: Determine whether the load status of the water multi-connection system is overloaded; If so, the cold water storage tank is controlled to enter the cooling replenishment state; After controlling the cold water tank to enter the cooling replenishment state, determine whether the load state of the water multi-connection system has switched to low load; If so, the cold water storage tank is controlled to enter a state of cold energy consumption.

9. The method according to claim 8, characterized in that, Controlling the cold water storage tank to enter the cooling replenishment state includes: Control the inlet and second outlet of the first valve to be open; control the first inlet, second inlet and outlet of the second valve to be open; control the fourth and fifth valves to be open, and the third valve to be closed; control the cooling water pump to be turned on; The cooling water pump is installed on the outlet pipe of the cooling water tank.

10. The method according to claim 9, characterized in that, After controlling the cold water tank to enter the cooling replenishment state, the method further includes: Control the speed of the make-up water pump so that the sum of the make-up water pump's flow rate and the outdoor unit's maximum water flow rate equals the sum of the indoor unit's required water flow rate.

11. The method according to claim 8, characterized in that, Controlling the cold water storage tank to enter a cooling capacity consumption state includes: The system controls the first valve inlet, first outlet, and second outlet to be closed; controls the second valve inlet and outlet to be open; controls the third and fifth valves to be closed and the fourth valve to be open; controls the cooling water pump to be turned on, and simultaneously controls the outdoor unit to be turned off.

12. The method according to claim 8, characterized in that, After controlling the cold water storage tank to enter a cooling replenishment state, or controlling the cold water storage tank to enter a cooling consumption state, the method further includes: Determine whether the water level in the cold water storage tank has reached the minimum water level; If so, the cold water storage tank will stop supplying cooling, and the outdoor unit will supply cooling independently.

13. The method according to claim 12, characterized in that, Controlling the cold water storage tank to stop supplying cooling and controlling the outdoor unit to supply cooling independently includes: Control the inlet and second outlet of the first valve to be open, and close the first outlet; control the first inlet and outlet of the second valve to be open, and close the second inlet; control the third and fourth valves to be open, and close the fifth valve; control the cooling water pump to be closed.

14. A water-based multi-split system, comprising an outdoor unit and an indoor unit, wherein a buffer water tank is installed on the return water pipe of the outdoor unit for implementing the control method as described in any one of claims 1-13, characterized in that, The water multi-connection system includes: The cold water storage tank has its inlet and outlet pipes connected to the outlet pipe of the outdoor unit, respectively. A bypass pipe is installed between the inlet pipe and the outlet pipe of the buffer water tank to bypass the water in the return pipe of the outdoor unit. The controller is used to control whether the cold storage tank enters the cold storage state according to the outdoor ambient temperature, to control whether the cold storage tank enters the supplemental cooling state or the cold energy consumption state according to the load state of the water multi-connection system, and to control the conduction state of the bypass pipeline.

15. The system according to claim 14, characterized in that, The water multi-connection system also includes: The first valve has its inlet connected to the water outlet pipe of the outdoor unit, its first outlet connected to the water inlet pipe of the cold water storage tank, and its second outlet connected to the first inlet of the second valve. The second valve has its second inlet connected to the outlet pipe of the cold water storage tank, and its outlet connected to the inlet pipe of the indoor unit and the inlet pipe of the floor heating equipment.

16. The system according to claim 14, characterized in that, The water multi-connection system also includes: The third valve is installed on the outlet pipe of the buffer water tank; The fourth valve is installed on the inlet pipe of the buffer water tank; The fifth valve is located on the bypass pipeline.

17. The system according to claim 14, characterized in that, The water multi-connection system also includes: A pressure balancing pipeline is installed between the cold water storage tank and the buffer tank, with its first end connected to the upper part of the cold water storage tank and its second end connected to the upper part of the cold water storage tank.

18. The system according to claim 14, characterized in that, The water multi-connection system also includes: A cooling water pump is installed on the outlet pipe of the cooling water tank.

19. An air conditioner comprising a water multi-split system as claimed in any one of claims 14 to 18, and further employing the control method as claimed in any one of claims 1 to 13.

20. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the control method as described in any one of claims 1 to 13.

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