Control method of variable shunt five-constant system

Abstract

The invention discloses a control method of a variable shunting five-constant system, and aims to solve the problem that a radiation heat exchange tube in a traditional five-constant system is easy to generate condensate water. The method intelligently controls the flow direction of the working medium and the running state of the coil pipe inner machine based on the environment temperature and humidity and the working medium temperature so as to avoid generation of condensate water. The method comprises the following specific steps: continuously detecting indoor environment temperature and humidity and the temperature of a working medium to enter a radiation heat exchange tube; judging whether condensate water is generated or not; if yes, dehumidification and working medium heating treatment is carried out; if not, the working medium is controlled to enter the radiation heat exchange tube for refrigeration; and the temperature of the working medium to enter the coil pipe inner machine is continuously detected, whether operation of the coil pipe inner machine can be stopped or not is judged, and finally temperature adjustment completely depends on the radiation heat exchange pipe. The method can effectively prevent condensate water from being generated, improve the comfort level, guarantee the'constant static 'effect, improve the system efficiency, give consideration to rapid cooling, and improve the flexibility and engineering friendliness of the system.

Description

Technical Field

[0001] This invention relates to an indoor environment control method, and more particularly to a control method for a variable flow distribution five constant system. Background Technology

[0002] In the field of contemporary indoor environmental control, the "Five Constant Systems" are gradually becoming a new benchmark in building environmental engineering as an integrated solution. This system cleverly combines five functions—constant temperature, constant humidity, constant oxygen, constant cleanliness, and constant quietness—aiming to create a near-perfect living space for residents. However, like any complex system, optimizing each subsystem presents unique challenges and opportunities.

[0003] In terms of temperature control, traditional convection air conditioning systems are gradually giving way to more advanced radiant cooling and heating technologies. This innovative method uses radiant panels installed on the roof, walls, or floor of a building, utilizing a water circulation system to achieve radiant heat exchange based on indoor temperature differences. This not only avoids the common problem of "direct cold air blowing" in traditional air conditioning systems but also significantly improves user comfort. Furthermore, this temperature control method generates extremely low noise during operation, perfectly aligning with the "constant quietness" concept among the "five constants" (constant temperature, constant humidity, constant temperature, constant air quality).

[0004] However, radiant panel temperature control technology is not without its flaws. Condensation during the cooling process presents a significant technical challenge. Currently, the industry standard solution involves installing dew point sensors in each room to monitor the dew point, enhancing the room's airtightness to prevent moisture from entering. The system's dehumidification function then handles the condensation. However, high-quality sealing demands stringent material requirements, leading to substantial cost increases and requiring advanced construction techniques, resulting in longer project durations. Furthermore, this approach presents new challenges: rapid cooling often necessitates the activation of high-power dehumidifiers to prevent visible condensation. This places higher demands on equipment performance, and the high energy consumption and noise levels associated with high-power operation contradict the goal of maintaining a quiet environment.

[0005] To address this challenge, some projects have adopted innovative methods, such as pre-embedding radiant heat exchange tubes directly into the building structure. This design concept does alleviate the condensation problem to some extent, utilizing building walls as a buffer to reduce condensation generation. However, this method inevitably introduces new problems: the insulation effect of the walls also reduces the efficiency of radiant temperature regulation. The heat exchange process first occurs between the pipes and the walls before affecting the indoor environment, which undoubtedly increases the system's response time and energy consumption.

[0006] Even more problematic is that in extreme cases requiring rapid cooling, even with a pre-embedded design, the possibility of condensation on the wall surface cannot be completely eliminated. This can not only affect the aesthetics of the room but also pose potential safety hazards.

[0007] Another solution is to use two sets of cryogenic working fluid systems, also known as a dual-cold source system. This undoubtedly increases costs, and the dual-cold source system requires its own piping to be coordinated and controlled, which increases the difficulty of design and installation many times over.

[0008] Therefore, in the continuous optimization of the "five constant systems", how to effectively solve the condensation problem in radiant temperature control technology while ensuring the overall performance of the system remains a technical challenge that urgently needs to be overcome. Summary of the Invention

[0009] To address the aforementioned issues, this invention provides a control method for a variable flow splitting five constant system, which can achieve both constant and static effects under the same system configuration and effectively reduce the possibility of condensate generation.

[0010] To achieve the above objectives, the present invention designs a variable flow five constant system, including a heat pump, a distribution module, a radiant heat exchange tube, a coil indoor unit, and high-temperature and low-temperature tubes containing a working fluid. The heat pump is connected to the distribution module through the high-temperature and low-temperature tubes, the distribution module is connected to the coil indoor unit through the high-temperature and low-temperature tubes, the coil indoor unit is connected to the radiant heat exchange tube through the high-temperature and / or low-temperature tubes, and a control valve is provided on the connecting pipe between the coil indoor unit and the radiant heat exchange tube.

[0011] The control method for a variable flow splitting five constant system described in this application mainly includes the following steps:

[0012] a) Continuously monitor the ambient temperature and humidity within the target space;

[0013] b) Continuously monitor the temperature of the working fluid to be introduced into the radiant heat exchanger tube;

[0014] c) Determine whether the temperature of the working fluid to be introduced into the radiant heat exchanger tube under the current humidity will cause condensation to form on the radiant heat exchanger tube. If condensation will form, proceed to step d); otherwise, proceed to step e.

[0015] d) Dehumidify the environment or simultaneously heat the working fluid to be introduced into the radiant heat exchanger tube, then return to step c);

[0016] e) Continuously control the working fluid to enter the radiant heat exchange tube to cool the ambient temperature;

[0017] f) Return to step a).

[0018] The characteristic of this method is that it determines whether to allow the working fluid to enter the radiant heat exchange tube based on the ambient temperature and humidity conditions in advance. The temperature regulation of the radiant heat exchange tube is only activated when it is ensured that no condensation will be generated, thereby eliminating the possibility of condensation.

[0019] A further method is to simultaneously cool the ambient temperature through the indoor unit with coils during dehumidification in step d). This prioritizes meeting the user's cooling needs.

[0020] To enable the radiant heat exchanger tubes to quickly enter the temperature control process, the working fluid to be introduced into the tubes comes from the indoor unit. The process of cooling the ambient temperature using the indoor unit in step d) heats the working fluid entering the tubes. The cooling operation of the indoor unit not only lowers the ambient temperature but also increases the temperature of the low-temperature working fluid from the heat pump, bringing the working fluid inside the tubes closer to its dew point and thus reducing the waiting time for the radiant heat exchanger tubes to operate.

[0021] In order to ensure that the indoor unit of the coil can smoothly exit the temperature regulation operation and achieve the "constant quietness" effect of the five constant systems, further, after completing step e), the following steps are performed:

[0022] g) Continuously monitor the temperature of the working fluid to be introduced into the indoor unit of the coil;

[0023] h) Determine whether the temperature of the working fluid to be introduced into the indoor unit under the current humidity will cause condensation to form on the radiant heat exchange tubes. If condensation is caused, proceed to step d); otherwise, proceed to step i).

[0024] i) Stop the operation of the indoor unit with coils;

[0025] j) Return to step e).

[0026] By continuously monitoring the temperature of the refrigerant entering the indoor unit, it is determined whether to stop the operation of the indoor unit, thus ensuring that no condensate is generated during the initial working stage of the radiant heat exchange tubes. The indoor unit is stopped only when the dew point in the room is lower than the target temperature, and the temperature adjustment is entirely completed by the radiant heat exchange tubes.

[0027] Of course, it should be noted that under the current technical conditions, the operation mode of the indoor unit is not simply to turn on or off. Therefore, as the detected ambient temperature and humidity gradually approach the target value, that is, as the dew point temperature calculated based on the ambient temperature and humidity gradually approaches the working fluid temperature after being heated by the indoor unit, the power of the indoor unit gradually decreases until the indoor unit stops running.

[0028] This invention addresses the problems of condensation easily generated in the radiant heat exchange tubes of existing five-constant systems during cooling mode, leading to the need for high-power dehumidification, affecting comfort and the "constant quiet" effect. It proposes a control method for a variable-flow five-constant system, the core of which lies in improving and optimizing the coil indoor unit function and system control strategy of existing five-constant systems:

[0029] Extended Functions of Indoor Unit with Coil: Fully utilize the temperature and humidity regulation functions of the original indoor unit with coil in the five constant system, enabling it to play a role in working fluid pretreatment in radiant cooling mode.

[0030] When the indoor unit with coils adjusts temperature and humidity, the temperature of the refrigerant passing through it rises, lowering the dew point temperature. This invention utilizes this characteristic by using a control valve to guide the refrigerant from the heat pump to the indoor unit with coils for pretreatment, thus preventing condensation from forming outside the radiant heat exchange tubes.

[0031] Dynamic adjustment of working fluid flow direction: By introducing a control valve, the system can intelligently switch the working fluid flow direction according to the ambient temperature and humidity and the working fluid temperature. When the ambient temperature and humidity are high and the working fluid temperature is low, posing a risk of condensation, the control valve directs the working fluid to the indoor unit coil for pretreatment, preventing it from entering the radiant heat exchange tubes. When the ambient temperature and humidity are low and the working fluid temperature is suitable, posing no risk of condensation, the control valve directs the working fluid to the radiant heat exchange tubes for efficient radiant cooling.

[0032] Intelligent control strategy: The system is equipped with temperature and humidity sensors and a control center, which can monitor environmental parameters and working fluid status in real time, and control the operation of valves and indoor units according to preset logic.

[0033] The control strategy can dynamically adjust the flow direction of the working fluid and the working status of the indoor unit according to environmental conditions, ensuring that the system operates efficiently while avoiding the generation of condensate.

[0034] Compared to existing five-constant systems, this technical solution achieves the following technical effects:

[0035] 1. Effectively prevents condensation: By dynamically adjusting the working fluid flow and the pre-treatment function of the indoor unit coil, condensation is effectively avoided in the radiant heat exchange tubes in cooling mode, eliminating the reliance on high-power dehumidification.

[0036] 2. Enhanced Comfort: Radiant heat exchange tubes provide a more uniform and comfortable temperature regulation, avoiding the direct blast of cold air and temperature fluctuations common in traditional air conditioners. Pre-treatment by the indoor unit's coils allows the radiant heat exchange tubes to participate in temperature regulation more quickly, further improving comfort.

[0037] 3. Ensure "constant quiet" effect: Avoid the noise caused by high-power dehumidification, achieve the "constant quiet" goal in the five constant systems, and create a quiet and comfortable indoor environment.

[0038] 4. Improved System Efficiency: Intelligent control strategies can adjust the working fluid flow and the operating status of the indoor unit coil according to actual needs, improving overall system efficiency and reducing energy consumption. Pre-treatment of the indoor unit coil shortens the start-up time of the radiant heat exchange tubes and also improves heat exchange efficiency.

[0039] 5. Simultaneous Rapid Cooling: The coil-type indoor unit can assist in cooling, meeting users' needs for rapid cooling, while simultaneously creating conditions for the start-up of the radiant heat exchange tubes. Optimized control strategies better coordinate the collaborative work of the coil-type indoor unit and the radiant heat exchange tubes.

[0040] 6. Flexible radiant heat exchanger tube arrangement: Since the condensation problem is effectively avoided, the radiant heat exchanger tubes can be arranged more flexibly in the target environment, such as being installed on the ceiling or wall in the form of a silent air conditioning panel, which improves the temperature regulation efficiency and reduces the difficulty of modifying existing projects.

[0041] 7. Enhanced Engineering Compatibility: Compared to solutions that require embedding radiant heat exchange tubes within building walls, this solution utilizes silent air conditioning panels for radiant heat exchange tubes, reducing the need for pipe modifications and facilitating integration with existing building structures, thus lowering construction costs and complexity. It is particularly suitable for secondary renovations; simply adding radiant panels composed of radiant heat exchange tubes to the existing ceiling and floor water systems can achieve a five-constant system.

[0042] 8. Simplified system design and modification: This invention cleverly utilizes the temperature and humidity regulation function of the original coil indoor unit in the five constant system. Only by adding a control valve and slightly changing the pipeline connection, it can realize the rapid start-up and efficient operation of the radiant heat exchange tube, which reflects the technological innovation concept of "low cost and high benefit". It is also more user-friendly and convenient for the modification of the existing five constant system.

[0043] In summary, the control method for the variable flow splitting five constant system proposed in this invention effectively solves the condensate problem of radiant heat exchange tubes in traditional five constant systems by ingeniously improving and optimizing the functions of the indoor unit coil and the system control strategy in existing five constant systems. While maintaining the advantages of existing five constant systems, it achieves efficient, comfortable and quiet indoor environment control, better meets users' needs for a "five constant" environment, and improves the system's flexibility and engineering friendliness. Attached Figure Description

[0044] Figure 1 This is the first type of pipeline connection diagram for the main components of the five constant systems in Example 1.

[0045] Figure 2 This is the second type of pipeline connection diagram for the main components of the five constant systems in Example 2.

[0046] Figure 3 This is a flowchart of the control method for a variable flow splitting five constant system. Detailed Implementation

[0047] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0048] Example 1.

[0049] like Figure 1 As shown, the variable flow five-constant system described in this embodiment includes a control center (control panel), a heat pump 1, a buffer energy storage tank, a distribution module 2, radiant heat exchange tubes 3, an indoor unit with coils 4, and high-temperature and low-temperature tubes containing the working fluid. Of course, for a five-constant system, it should also include components related to fresh air, filtration systems, and automated control, which will not be elaborated here. The working fluid is generally water. The high and low temperatures in the high-temperature and low-temperature tubes are relative concepts, mainly representing the temperature difference of the working fluid within the two tubes. In cooling mode, the inlet water tube is the low-temperature tube, while the outlet water tube after heat exchange is the high-temperature tube.

[0050] The heat pump 1 is first connected to a buffer storage water tank via high-temperature and low-temperature pipes, and then connected to the distribution module 2. The distribution module 2 is connected to the indoor unit 4 via a first high-temperature pipe 6 and a first low-temperature pipe 5. The indoor unit 4 is connected to the radiant heat exchange tube 3 via a second high-temperature pipe 8 and / or a second low-temperature pipe 7, and a control valve 9 is provided on the connecting pipe between the indoor unit 4 and the radiant heat exchange tube 3. Whether the indoor unit 4 is connected via the second high-temperature pipe 8, the second low-temperature pipe 7, or both, can be determined based on the actual situation of the project. However, to effectively reduce the possibility of condensation, it is generally necessary to ensure that the second low-temperature pipe 7 connects the indoor unit 4 and the radiant heat exchange tube 3 together.

[0051] In this embodiment, the indoor unit 4 with a coil is connected to the radiant heat exchange tube 3 via the second low-temperature tube 7, and the radiant heat exchange tube 3 is directly connected to the distribution module 2 via the second high-temperature tube 8. That is, the working fluid after heat exchange through the radiant heat exchange tube 3 flows back to the heat pump 1 directly through the distribution module 2.

[0052] For ease of control, the control valve 9 can selectively connect the first low-temperature pipe 5 to the second low-temperature pipe 7 after passing through the coiled indoor unit 4, or directly connect the first low-temperature pipe 5 to the first high-temperature pipe 6 after passing through the coiled indoor unit 4. A temperature sensor 10 is installed on the coiled indoor unit 4 to monitor the temperature of the working fluid after passing through it. Simultaneously, the temperature sensor 10 is connected to the control center, which in turn is connected to the control valve 9 to issue commands to it.

[0053] The radiant heat exchange tubes 3 are multiple and connected in parallel, respectively corresponding to an external air conditioning heat exchange plate that can be directly used indoors, a radiant heat exchange capillary tube installed in the building components at the top of the room, a radiant heat exchange capillary tube installed in the building components at the bottom of the room, and a commonly known floor heating pipe installed in the floor slab.

[0054] like Figure 3 As shown, the specific steps of the control method for the variable current splitting five constant system described in this embodiment are as follows:

[0055] a) Continuously monitor the ambient temperature and humidity within the target space, i.e., indoors;

[0056] b) Continuously monitor the temperature of the working fluid to be introduced into the radiant heat exchanger tube 3;

[0057] c) Determine whether the temperature of the working fluid to be introduced into the radiant heat exchanger tube 3 under the current humidity will cause condensation to form on the radiant heat exchanger tube 3, that is, the relationship between the indoor dew point temperature and the working fluid temperature in step b). If condensation will occur, proceed to step d); otherwise, proceed to step e).

[0058] d) Dehumidify the environment or simultaneously heat the working fluid to be introduced into the radiant heat exchanger tube 3. Generally, dehumidification alone takes a long time. Therefore, in this embodiment, the working fluid to be introduced into the radiant heat exchanger tube is heated simultaneously. Then, return to step c) to make a judgment again.

[0059] e) Continuously control the working fluid to enter the radiant heat exchange tube 3 to cool the ambient temperature;

[0060] f) Return to step a).

[0061] Under normal circumstances, a five-constant system can maintain indoor temperature and humidity within a comfortable range while operating continuously. However, it is impossible to avoid unexpected situations that could cause sudden changes in indoor temperature and humidity. Therefore, it is required that when implementing control measures, the ambient temperature and humidity must be continuously monitored, and the above steps must be repeated cyclically.

[0062] In the above control method, the indoor unit 4 will act as the return air outlet after dehumidifying the ambient air. Since the dehumidified air will be slightly warmer than before dehumidification, the indoor unit 4 will also cool the dehumidified air. This cooling will cause the temperature of the working fluid entering the indoor unit 4 through the first low-temperature pipe 5 to rise. On the other hand, during the initial cooling or when rapid cooling is required, if the radiant heat exchanger 3 does not perform temperature regulation, the indoor unit 4 needs to initiate the cooling process in response to the user's operation. This will also cause the temperature of the working fluid entering the indoor unit 4 to rise. In this embodiment, the indoor unit 4 is connected to the radiant heat exchanger 3 through the second low-temperature pipe 7, that is, the outlet pipe of the indoor unit 4 is connected to the inlet pipe of the radiant heat exchanger 3. At this time, the temperature of the working fluid entering the radiant heat exchanger 3 has a certain temperature difference compared to the working fluid from the heat pump 1, that is, the working fluid is closer to the dew point of the environment.

[0063] To meet the requirements of "constant temperature" and "constant quietness", the subsequent control methods are as follows:

[0064] g) Continuously monitor the temperature of the working fluid to be introduced into the indoor unit 4 of the coil;

[0065] h) Determine whether the temperature of the working fluid to be introduced into the indoor unit 4 under the current humidity will cause condensation to form on the radiant heat exchange tube 3. If condensation is generated, proceed to step d); otherwise, proceed to step i).

[0066] i) Stop the operation of indoor unit 4;

[0067] j) Return to step e).

[0068] It should be noted that when the ambient temperature and humidity approach the target value, the power of the indoor unit 4 gradually decreases until the indoor unit 4 stops operating.

[0069] Example 2.

[0070] like Figure 2 As shown, the main difference between the variable flow splitting five constant system described in this embodiment and Embodiment 1 is that the indoor unit 4 with a coil is connected to the radiant heat exchange tube 3 through the second low-temperature tube 7 and the second high-temperature tube 8. That is, the working fluid after heat exchange through the radiant heat exchange tube 3 continues to flow back to the indoor unit 4 with a coil, and then flows back to the heat pump 1 through the first high-temperature tube 6 and the distribution module 2.

[0071] The main difference between its control method and that of Example 1 lies in step g): continuously monitoring the temperature of the working fluid after passing through the coil indoor unit 4.

[0072] Since the purpose of the control method is to ensure that the temperature of the working fluid entering the radiant heat exchanger tube 3 exceeds the ambient dew point, as the control process progresses, the power of the indoor unit 4 gradually decreases, and the temperature of the working fluid after passing through the indoor unit 4 will approach the initial working fluid temperature output by the heat pump 1. Therefore, the effect of this monitoring method is not significantly different from that of the method in Example 1. However, it reduces one temperature monitoring point, thus lowering the cost. Furthermore, if necessary, the result can be obtained through compensation calculation during the judgment calculation, completely eliminating the need to consider the impact of temperature errors.

[0073] Furthermore, it should be pointed out that the control valve 9 in this embodiment not only controls opening and closing, but also controls the flow rate of the working fluid. This not only makes the temperature adjustment process more comfortable, but also makes the transition process from independent temperature adjustment of the indoor unit 4 to combined temperature adjustment of the indoor unit 4 and the radiant heat exchange tube 3, and finally to independent temperature adjustment of the radiant heat exchange tube 3 more stable.

[0074] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0075] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or a signal connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0076] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method of a variable split five-constant system, the five-constant system comprising a heat pump, a distribution module, a radiant heat exchange pipe, a coil indoor unit, and high-temperature and low-temperature pipes in which a working medium is provided, the heat pump being connected to the distribution module through the high-temperature and low-temperature pipes, the distribution module being connected to the coil indoor unit through the high-temperature and low-temperature pipes, the coil indoor unit being connected to the radiant heat exchange pipe through the high-temperature and / or low-temperature pipes, and a control valve being provided on a connection pipe between the coil indoor unit and the radiant heat exchange pipe, characterized in that The control method comprises the following steps: a) continuously detecting the temperature and humidity of the environment in the target space; b) continuously detecting the temperature of the working medium to be introduced into the radiation heat exchange pipe; c) determining whether the temperature of the working medium to be introduced into the radiation heat exchange pipe under the current humidity will cause condensate to be generated on the radiation heat exchange pipe, and if so, step d) is performed, otherwise step e) is performed; d) dehumidifying the environment or simultaneously raising the temperature of the working medium to be introduced into the radiation heat exchange pipe, and then returning to step c); e) continuously controlling the working medium to be introduced into the radiation heat exchange pipe to reduce the temperature of the environment; f) returning to step a).

2. The control method of a variable split five-constant system according to claim 1, characterized by When dehumidifying the environment in step d), the temperature of the environment is simultaneously reduced by the indoor unit of the coil.

3. The control method of a variable split five-constant system according to claim 2, characterized by The working medium to be introduced into the radiation heat exchange pipe is from the indoor unit of the coil, and the working medium to be introduced into the radiation heat exchange pipe is raised in temperature through the process of reducing the temperature of the environment by the indoor unit of the coil in step d).

4. The control method of a variable split five-constant system according to claim 3, characterized by When step e) is completed, the following steps are performed: g) continuously detecting the temperature of the working medium to be introduced into the indoor unit of the coil; h) determining whether the temperature of the working medium to be introduced into the indoor unit of the coil under the current humidity will cause condensate to be generated on the radiation heat exchange pipe, and if so, step d) is performed, otherwise step i) is performed; i) stopping the operation of the indoor unit of the coil; j) returning to step e).

5. The control method of a variable split five constant system according to any one of claims 2 to 4, characterized by When the temperature and humidity of the environment approaches the target value, the power of the indoor unit of the coil is gradually reduced until the operation of the indoor unit of the coil is stopped.

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