Intelligent pre-cooling device

Abstract

The application discloses an intelligent precooling device, and particularly relates to the field of air conditioner outdoor unit precooling, and comprises a data acquisition module, a control operation module and an internet of things communication module. The intelligent precooling device is provided with sensing units on the windward side and the air outlet side of a wet membrane through the data acquisition module, core thermal and humid conditions parameters of the evaporative cooling process are obtained, and accurate real-time environmental data basis is provided for dynamic closed-loop control; the evaporative cooling efficiency is calculated through the efficiency calculation unit and the water pump control unit, the water pump control instruction is compared and generated, the optimal matching of cooling benefits and water resource consumption is realized while the precooling effect of the air conditioner condenser inlet air is ensured, and the invalid water circulation without benefits is avoided from the root; the energy-saving estimation unit is used for real-time measurement and accumulation of the power saving amount, the core pain point that the existing technology cannot quantize the precooling effect on the air conditioner refrigeration cycle performance improvement is solved, and the accurate and real-time measurement of the energy-saving benefits of the precooling device is realized.

Description

Technical Field

[0001] This invention relates to the field of air conditioner outdoor unit pre-cooling technology, and more specifically, to an intelligent pre-cooling device. Background Technology

[0002] In key energy-saving building scenarios such as communication base stations, data centers, and industrial parks, air conditioning equipment in energy-efficient refrigeration systems, especially outdoor units of air-cooled chillers or dedicated air conditioners for computer rooms, is typically concentrated in limited spaces such as rooftops. During the high-temperature period in summer, the heat dissipated by the outdoor units, combined with solar radiation, easily creates a "heat island effect" around them. This directly leads to increased condensing pressure, a sharp decrease in cooling capacity, and a significant increase in compressor power consumption. This becomes a core pain point that hinders the achievement of building energy-saving goals and threatens the continuous and reliable operation of the system. In severe cases, it can even trigger high-pressure alarms or system shutdowns.

[0003] Currently, the main solution to alleviate the above problems is the evaporative cooling pad pre-cooling technology. This technology utilizes the isenthalpic humidification process of water evaporation absorbing heat, installing an evaporative cooling pad mechanism on the air intake side of the outdoor unit as an energy-saving heat exchange device, and configuring a water circulation system and a timer or water level control unit to pre-cool the incoming air. Due to its relatively simple structure and low cost, it alleviates the heat dissipation pressure of the outdoor unit to a certain extent under high-temperature environments.

[0004] However, in actual use, it still has some shortcomings. For example, the existing control logic is mostly based on coarse timing or water level threshold triggering, which cannot dynamically adjust the working state of the wet curtain according to real-time meteorological parameters. This often leads to a serious mismatch between ineffective water consumption and cooling benefits, deviating from the purpose of refined management of energy-saving air conditioning technology and building energy conservation.

[0005] The existing devices' evaporative cooling pad fixing structures mostly use bolts or clips, which are either non-removable or complex to install and disassemble. This means that replacing the evaporative cooling pad, which is the core of the energy-saving heat exchange device, requires the use of special tools, which greatly increases maintenance time and unplanned downtime of the air conditioning equipment, raising the overall life cycle maintenance cost.

[0006] Existing solutions lack quantitative energy efficiency assessment methods based on thermodynamic models, and cannot combine enthalpy-humidity diagrams and pressure-enthalpy diagrams to calculate the changes in refrigeration cycle performance before and after precooling, making it difficult to obtain accurate energy-saving data to verify the actual benefits of energy-saving refrigeration retrofits. Summary of the Invention

[0007] In order to overcome the above-mentioned defects of the prior art, the present invention provides an intelligent precooling device, which solves the problems mentioned in the background art through the following solution.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A smart pre-cooling device includes a wet film, a water supply assembly, and a controller installed on the air inlet side of an outdoor air conditioning unit, and further includes:

[0010] Data acquisition module: used to acquire air thermal and humidity state parameters characterizing the wet film precooling process, including at least an inlet-side sensing unit for acquiring inlet air temperature parameters and an outlet-side sensing unit for acquiring outlet air temperature parameters.

[0011] Control and calculation module: used to generate water pump control commands and calculate power saving based on the air thermal and humidity parameters. Its execution unit includes at least: an efficiency calculation unit, used to calculate the actual evaporative cooling efficiency of the wet film in real time; a water pump control unit, used to compare the calculated actual evaporative cooling efficiency with a preset efficiency threshold, and generate a water pump control signal for adjusting the wet film wetting state based on the comparison result; and an energy saving estimation unit, used to calculate the power saving achieved by pre-cooling operation in real time based on the actual temperature drop and the pre-stored correspondence between condensing temperature and compressor power consumption.

[0012] IoT communication module: used to receive energy-saving related data output by the control and calculation module, and upload the energy-saving related data to a remote server or user terminal.

[0013] Preferably, the water supply assembly includes a water tank installed at the bottom of the air inlet side of the outdoor unit of the air conditioner. The water tank has a support edge near its edge, and a wet film frame is placed on the support edge. The wet film is disposed within the wet film frame. A water pump and a float valve are installed inside the water tank. A water pipe is installed at the outlet of the water pump. The water pipe has a downward-facing hole, and water can flow down from the hole to wet the wet film. A controller is provided on the wet film frame.

[0014] Preferably, the data acquisition module has an inlet-side sensing unit located on the windward side of the wet film, and an outlet-side sensing unit located in the closed negative pressure chamber between the wet film and the outdoor unit of the air conditioner, including:

[0015] Inlet dry bulb temperature sensor is used to collect the inlet dry bulb temperature Td1 before it enters the wet film;

[0016] Inlet air wet-bulb temperature sensor is used to collect the inlet air wet-bulb temperature Twb before it enters the wet film;

[0017] The outlet dry bulb temperature sensor is used to collect the outlet dry bulb temperature Td2 after flowing through the wet film.

[0018] Preferably, the inlet wet-bulb temperature sensor includes a temperature sensing probe and an absorbent cotton gauze sleeve wrapped around the probe. The lower end of the cotton gauze sleeve is immersed in a water supply container, and the probe surface is kept moist by capillary action.

[0019] Preferably, the efficiency calculation unit includes:

[0020] When the difference between the inlet dry-bulb temperature Td1 and the inlet wet-bulb temperature Twb is detected, the theoretical maximum cooling capacity is... When Td1-Twb is less than the preset minimum threshold, a water pump stop signal is generated directly to forcibly shut down the water pump.

[0021] Preferably, the preset efficiency threshold in the water pump control unit includes a start-up threshold. and stopping threshold And satisfy ;

[0022] Wherein, the stop threshold The start-up threshold is determined based on the evaporative cooling efficiency calibration value when there are no obvious macroscopic dry spots on the wet film outlet side. The evaporative cooling efficiency calibration value is determined based on the point at which the outlet air temperature rises above a preset value compared to the fully humidified state.

[0023] Preferably, the water pump control unit further includes:

[0024] Calculate the actual evaporative cooling efficiency Compared with the preset target efficiency value Deviation between ;

[0025] When the absolute value of the deviation e exceeds the preset dead zone range, the duty cycle of the pulse width modulation signal is generated based on the proportional coefficient Kp and the integral coefficient Ki. The pulse width modulation signal is then output to the water pump to continuously adjust its speed.

[0026] When the absolute value of the deviation e is within the preset dead zone range, the duty cycle of the current pulse width modulation signal remains unchanged.

[0027] Preferably, the pre-stored relationship between condensing temperature and compressor power consumption in the energy-saving estimation unit is a configurable coefficient k, and the controller obtains the rated power of the air conditioner compressor. include:

[0028] Receives the rated power value manually input via the configuration interface; or

[0029] The IoT communication module establishes data communication with the air conditioning unit's monitoring system to read the compressor's real-time operating power at preset intervals, and uses the sliding average of the read values ​​as the rated power. .

[0030] Preferably, the energy-saving related data of the IoT communication module includes at least one of the following: inlet dry-bulb temperature, wet-bulb temperature, outlet dry-bulb temperature, evaporative cooling efficiency of the wet film, real-time power saving, and cumulative power saving.

[0031] The technical effects and advantages of this invention are as follows:

[0032] 1. This invention acquires core thermal and humidity parameters of the evaporative cooling process by placing sensing units on the windward and air-outward sides of the wet film through a data acquisition module. This replaces the crude timing or water level threshold triggering method in the prior art, providing a precise real-time environmental data foundation for the dynamic closed-loop control of energy-saving heat exchange devices, and supporting the refined management of energy-saving air conditioning technology from the perception level.

[0033] 2. This invention calculates the evaporative cooling efficiency through an efficiency calculation unit and a water pump control unit, and generates water pump control commands by comparison. While ensuring the pre-cooling effect of the condenser air intake of the air conditioning equipment, it achieves the optimal match between cooling benefits and water consumption. It solves the problem that the existing technology cannot determine whether the working condition has effective cooling value, and avoids ineffective water circulation without benefits from the root, directly serving the core goal of building energy conservation.

[0034] 3. This invention solves the core pain point of existing technologies that cannot quantify the improvement of air conditioning refrigeration cycle performance by real-time measurement and accumulation of power saving through energy-saving estimation unit. It realizes accurate, real-time measurement and visualization of the actual benefits of energy-saving refrigeration retrofit measures, and provides a reliable data closed loop for operation and maintenance parties to optimize building energy-saving operation strategies. Attached Figure Description

[0035] Figure 1 This is an isometric view of the overall structure of an intelligent precooling device provided according to an embodiment of this application.

[0036] Figure 2 This is a block diagram of an intelligent precooling device provided according to an embodiment of this application.

[0037] Figure 3 This is a flowchart illustrating the efficiency calculation unit provided according to an embodiment of this application.

[0038] Figure 4 This is a flowchart illustrating the start-stop control mode in a water pump control unit provided according to an embodiment of this application.

[0039] Figure 5 This is a flowchart illustrating the flow regulation mode in the water pump control unit provided according to an embodiment of this application.

[0040] Explanation of reference numerals in the attached diagram: 1. Outdoor unit of air conditioner; 2. Controller; 3. Water pump; 4. Water tank; 5. Wet film; 6. Float valve; 7. Water pipe. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The terminology used in the following embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to include the plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this application refers to and includes any or all possible combinations of one or more of the listed items. In the description of the embodiments of this application, unless otherwise stated, “a plurality” means two or more.

[0043] As attached Figure 1 The illustrated intelligent pre-cooling device is installed on the air inlet side of the outdoor unit 1 of an air conditioner, specifically designed for use in high heat density environments such as communication base stations, data centers, or industrial parks. Figure 2 The physical architecture of the device integrates three main functional modules: a data acquisition module, a control and computing module, and an IoT communication module. Spatially, it is integrated into a single unit using a wet film 5 as its frame, forming an additional device independent of the outdoor unit 1, facilitating on-site installation and subsequent maintenance. The wet film 5 refers to a hydrophilic fibrous material product with a three-dimensional honeycomb or corrugated structure, capable of adsorbing moisture through capillary action and facilitating heat and moisture exchange between the air and the water film. The outer frame of the precooling device is directly connected to the air inlet face of the outdoor unit 1 or connected through a flexible air duct, forming a relatively closed negative pressure chamber between them. Utilizing the suction negative pressure generated by the condenser fan of the outdoor unit 1, the high-temperature outdoor air is forced to flow through the wet film 5 inside the precooling device before entering the condenser fin surface, thus completing air pretreatment without adding additional ventilation power components.

[0044] The data acquisition module is used to acquire air thermal and humidity parameters characterizing the precooling process of the wet film 5. Physically, it includes at least an inlet-side sensing unit for acquiring inlet air temperature parameters and an outlet-side sensing unit for acquiring outlet air temperature parameters. The inlet-side sensing unit is located on the windward side of the wet film 5, specifically on the inlet surface of the wet film frame or inside the inlet louvers of the precooling device housing. It includes an inlet dry-bulb temperature sensor and an inlet wet-bulb temperature sensor. The inlet dry-bulb temperature sensor acquires the inlet dry-bulb temperature Td1 before entering the wet film 5; the inlet wet-bulb temperature sensor uses a temperature-sensing element wrapped in moistened cotton yarn to acquire the inlet wet-bulb temperature Twb before entering the wet film 5. The outlet-side sensing unit includes an outlet dry-bulb temperature sensor located in the negative pressure chamber between the wet film 5 and the outdoor unit 1 of the air conditioner, acquiring the outlet dry-bulb temperature Td2 after flowing through the wet film 5. The installation position of the air outlet side sensing unit should avoid areas where water droplets may splash on the surface of the wet film 5, and ensure that the temperature probe is in the uniformly mixed airflow after passing through the wet film 5. Simultaneously, all the above sensors are electrically connected to the controller 2, transmitting the collected temperature data to the input port of the controller 2 in real time.

[0045] The inlet dry-bulb temperature sensor preferably uses a thermistor or thermocouple type temperature sensing element. Its temperature probe is exposed in the airflow to collect the inlet dry-bulb temperature before entering the wet film 5. The inlet wet-bulb temperature sensor includes a temperature sensing probe and an absorbent cotton gauze sleeve wrapped around the probe, the lower end of which is immersed in a small water replenishment container. The water replenishment container is connected to the water tank 4 of the intelligent water circulation module via a flexible thin tube. The tube diameter is 2mm to 4mm, utilizing capillary action to automatically replenish small amounts of water to the water replenishment container, maintaining the continuous moisture of the gauze sleeve. The capacity of the water replenishment container is designed to maintain continuous operation for more than 72 hours. The water replenishment container is connected to the water tank 4 of the intelligent water circulation module via a thin tube to achieve automatic water replenishment, avoiding frequent manual water addition. When outdoor air flows over the surface of the moistened probe, the water evaporates, carrying away heat and causing the probe temperature to drop to the wet-bulb temperature. Both the inlet dry-bulb temperature sensor and the inlet wet-bulb temperature sensor are configured. When Twb approaches Td1 (… If the temperature is below 2℃ (i.e., high humidity condition), the theoretical maximum cooling potential is already extremely limited, so it is determined that there is no need to turn on water pump 3 to avoid ineffective water resource consumption.

[0046] The outlet-side sensing unit includes at least one outlet dry-bulb temperature sensor for acquiring the outlet dry-bulb temperature Td2 after pre-cooling by the wet film 5. Preferably, the same model and accuracy temperature sensing element as the inlet dry-bulb temperature sensor is used to ensure that the error between the measured values ​​of Td1 and Td2 is minimized.

[0047] Each sensor is electrically connected to controller 2 in the control and computing module. The following connection methods can be selected according to actual engineering requirements: If the sensor output is an analog signal (4-20mA current signal or 0-10V voltage signal), it is connected to the analog input terminal of controller 2 via a shielded cable. The built-in analog-to-digital converter circuit of controller 2 converts the analog signal into a digital signal. If the sensor output is a digital signal, it is connected to the serial communication interface of controller 2 via a two-core shielded twisted-pair cable. Controller 2 sends read commands to each sensor according to a preset polling cycle and receives the returned temperature data.

[0048] The configuration and parameters of the temperature monitoring sensor are shown in Table 1 below:

[0049] Table 1

[0050]

[0051] After receiving temperature data from each sensor, controller 2 performs digital filtering to eliminate instantaneous measurement noise caused by airflow disturbances or electromagnetic interference. The filtered values ​​of Td1, Twb, and Td2 are used as input variables for the efficiency calculation unit in the control operation module.

[0052] The control and calculation module is installed in the electrical control box on the side wall of the precooling device. It generates water pump control commands based on the air heat and humidity parameters acquired by the data acquisition module and outputs them to water pump 3. Simultaneously, it outputs the calculated energy-saving data to the IoT communication module. Physically, this is the controller 2 and its internal software program within the device of this invention. The controller 2, as a hardware carrier, has internal logic units that include at least the data processing and command generation functions of the efficiency calculation unit, water pump control unit, and energy-saving estimation unit. Preferably, a 32-bit embedded microcontroller based on the ARM Cortex-M series core is used, with a built-in central processing unit, random access memory, and flash memory. The flash memory is used to store the program instructions corresponding to the efficiency calculation unit, water pump control unit, and energy-saving estimation unit, as well as parameter data such as preset efficiency thresholds and the relationship between condensing temperature and compressor power consumption. The random access memory is used to temporarily store the real-time values ​​of Td1, Twb, and Td2 input from the data acquisition module, as well as intermediate calculation results. The central processing unit executes the program instructions one by one to complete data processing tasks such as evaporative cooling efficiency calculation, threshold comparison, and power saving calculation. The signal interface configuration of the controller 2 is shown in Table 2 below.

[0053] Table 2

[0054]

[0055] The efficiency calculation unit's function is stored in the flash memory of controller 2 as program instructions, and it calculates the actual evaporative cooling efficiency of the wet film 5 in real time. In one specific embodiment, the execution cycle is set to 1 second, meaning that controller 2 completes a full cycle every second, from reading sensor data, calculating efficiency, comparing thresholds, updating water pump control instructions, to accumulating energy savings. It should be noted that if the sensor response time is greater than 1 second, sampling once per second and adjusting water pump 3 accordingly may lead to control lag or oscillation. However, in this scheme, the water temperature change and the wetting process of the wet film 5 are inherently slow, and a 1-second sampling and control cycle is reasonable in engineering and does not violate common sense.

[0056] Within each preset execution cycle, controller 2 reads the real-time values ​​of inlet dry-bulb temperature Td1, inlet wet-bulb temperature Twb, and outlet dry-bulb temperature Td2 provided by the data acquisition module through its analog input interface, completing the data input operation; the efficiency calculation unit uses the above Td1, Twb, and Td2 to calculate the actual evaporative cooling efficiency of the wet film 5. and will The value is stored in random access memory, which serves as the input basis for the water pump control unit within this cycle; the water pump control unit reads... The efficiency calculation unit compares the value with a preset efficiency threshold, generates and outputs a water pump control signal to water pump 3 based on the comparison result; the energy saving estimation unit uses Td1 and Td2 to calculate the actual cooling range, and combines the pre-stored correspondence between condensing temperature and compressor power consumption to calculate the incremental energy saving within the current cycle and accumulate it to the cumulative energy saving register. The efficiency calculation unit, water pump control unit and energy saving estimation unit all complete their operations within the same execution cycle, and there is no data dependency between the energy saving estimation unit and the water pump control unit, so they can be executed in parallel or in any order.

[0057] As attached Figure 3 The steps for calculating the evaporative cooling efficiency are as follows: Calculate the theoretical maximum cooling capacity. =Td1-Twb, used to characterize the upper limit of temperature reduction achievable by evaporative cooling technology under current ambient wet-bulb temperature conditions; when If the temperature approaches zero, the wet film 5 is in a perfectly wetted state, and the air temperature cannot decrease significantly. Calculate the actual temperature drop. =Td1-Td2, used to characterize the actual cooling effect produced by the wet film 5 precooling device. Calculate the evaporative cooling efficiency. It should be noted that when detected... When the temperature falls below the preset minimum threshold (0.5°C), it indicates that the ambient air is close to or has reached saturation, and the evaporative cooling potential is almost zero. This directly generates a water pump stop signal, regardless of the current temperature. Regardless of the calculated value, water pump 3 will be forcibly shut down to avoid unnecessary water consumption. Simultaneously, to prevent overflow during division, the efficiency calculation unit will directly... Assign a value of 0. As a preferred energy-saving strategy, when... At temperatures below 2°C, even if the temperature has not yet dropped below 0.5°C, the water pump control unit will prioritize responding and generate a stop command to further conserve water under higher wet-bulb temperature conditions. The efficiency calculation unit will calculate the... The value is stored in the random access memory of controller 2 for use by the water pump control unit within the same execution cycle. It should be noted that this invention is the first to embed the evaporative cooling efficiency calculation formula into the embedded controller in real time.

[0058] The water pump control unit utilizes the evaporative cooling efficiency output by the efficiency calculation unit. The controller 2 dynamically generates a water pump control signal based on a preset efficiency threshold to achieve closed-loop regulation of the wetting state of the wet film 5. Its function is also stored as program instructions in the flash memory of the controller 2. The water pump control unit can operate in any of the following control modes, which can be selected by configuring parameters before delivery or during commissioning according to actual engineering requirements:

[0059] As attached Figure 4 As shown, the preset efficiency thresholds include the startup threshold. and stopping threshold And satisfy In one basic implementation, the activation threshold... Set to 0.70, stop threshold The value is set to 0.85 to prevent water pump 3 from frequently starting and stopping near the threshold. If... If the current evaporative cooling efficiency of the wet film 5 has dropped to an unacceptably low level, the controller 2 generates a start command and outputs a closing signal to the water pump 3 through the digital output interface. The water pump 3 is powered on and pumps water from the water tank 4 to the water pipe 7 and sprays it onto the surface of the wet film 5 through the water distribution holes to replenish the water film. If the wet film 5 has recovered to the ideal wetting level, continuing to supply water would be wasteful. Controller 2 generates a stop command and outputs a disconnect signal to water pump 3, causing water pump 3 to stop operating. Controller 2 maintains its current output state.

[0060] In another alternative implementation, as shown in the appendix Figure 5 As shown, water pump 3 is a DC brushless water pump with stepless speed regulation via pulse width modulation signals. Controller 2 reads the current evaporative cooling efficiency generated by the efficiency calculation unit. And retrieve the target efficiency pre-stored in memory. , Set to 0.80. Controller 2 calculates the efficiency deviation. To avoid frequent speed adjustments of water pump 3 due to measurement noise or minor fluctuations, controller 2 determines the deviation. If the deviation e is within the preset dead zone range, controller 2 maintains the duty cycle of the current output pulse width modulation signal unchanged and directly ends the adjustment of this cycle. If the deviation e exceeds the dead zone range, controller 2 performs proportional-integral calculation: calculating the contribution value of the proportional term respectively. and cumulative value of integral terms And according to the formula Generate a new pulse width modulation signal duty cycle ,in This is the proportionality coefficient. The integral coefficients are denoted as Kp and Ki, respectively. The proportional coefficient Kp is 5.0, and the integral coefficient Ki is 0.2. These parameters are tuned based on a duty cycle output range of 0–100% and an efficiency deviation e dimensionless range of approximately [-1, 1]. The specific values ​​of Kp=5.0 and Ki=0.2 are obtained by establishing a transfer function model of the wet film evaporative cooling process (first-order inertia plus pure delay), using the critical proportionality method in MATLAB / Simulink simulation tuning, and then verifying the optimal parameters through actual prototype testing. This parameter combination enables the system to recover η to the target value ±0.02 within 60 seconds after being disturbed by inlet air temperature and humidity, without overshoot oscillation, thus obtaining the optimal value suitable for specific installation conditions. The dead zone is set to |e| < 0.02, i.e., when the efficiency... When the duty cycle is between 0.78 and 0.82, controller 2 does not adjust the PWM duty cycle to avoid control oscillations caused by measurement noise. Controller 2 adjusts the calculated duty cycle... Output limiting is performed: if D is less than the preset lower limit (20%), the duty cycle is forcibly set to 20%; if D is greater than the preset upper limit (100%), the duty cycle is forcibly set to 100%; if D is between 20% and 100%, the actual calculated value is output. Controller 2 outputs the pulse width modulation signal with the limited duty cycle to water pump 3 through the pulse width modulation output interface. The speed of water pump 3 changes continuously accordingly, thereby linearly adjusting the amount of water sprayed onto the wet film 5 through water pipe 7. The change in water volume causes a change in the wetting state of the wet film 5, thereby affecting the evaporative cooling efficiency. Towards target efficiency Convergence forms a closed-loop continuous regulation.

[0061] Optionally, controller 2 can be configured based on the theoretical maximum cooling capacity. Dynamically adjust the dead zone range; when When the temperature is low (<5°C), the dead zone range is automatically expanded to |e|<0.05 to avoid problems caused by high humidity conditions. The fluctuations in the calculations caused the water pump speed to be adjusted frequently.

[0062] The energy-saving estimation unit is stored in the flash memory of controller 2 as program instructions. It uses the pre-stored relationship between condensing temperature and compressor power consumption in controller 2, combined with the actual temperature drop, to calculate the energy savings achieved during pre-cooling operation in real time. The pre-stored relationship between condensing temperature and compressor power consumption (coefficient k ≈ 0.025 / °C) is invoked. Coefficient k represents the percentage reduction in compressor power consumption for every 1°C decrease in condensing temperature; this relationship is a well-known conclusion in the refrigeration field based on pressure-enthalpy diagram analysis. When k is 0.025 / °C, it corresponds to a 2.5% reduction in compressor power consumption for every 1°C decrease in condensing temperature. Because the actual performance curves of different compressor types and different refrigerants differ, controller 2's flash memory pre-stores a configurable range of k values ​​(0.02 / °C to 0.03 / °C). Engineers can select the corresponding k value through the configuration interface according to the specific compressor type of the outdoor unit 1 to improve the accuracy of energy-saving estimation. In one embodiment, for a typical R410A air conditioning system operating at a condensing temperature of 45°C and an evaporating temperature of 5°C, according to the pressure-enthalpy diagram, the compressor power consumption per unit cooling capacity is 0.35 kW / kW. When the condensing temperature decreases by 1°C to 44°C, the compressor power consumption per unit cooling capacity drops to 0.342 kW / kW, a decrease of approximately 2.3%. This verifies that the k-value is around 0.023 / °C. This invention adopts the median value of 0.025 / °C as the default coefficient.

[0063] Since the precooling device directly reduces the inlet air temperature of the condenser of the outdoor unit 1 of the air conditioner, the reduction in inlet air temperature is approximately equal to the reduction in condensing temperature. Controller 2 uses the formula... Real-time estimation of power savings, of which This refers to the rated input power of the compressor in outdoor unit 1 of the air conditioner. The power value is acquired and stored in the flash memory of controller 2 in one of the following ways: During the initial power-on debugging of the device, the installer manually inputs the rated power value of the outdoor unit 1 via a handheld configuration terminal or local button interface. Controller 2 stores this value in flash memory and retrieves it in subsequent calculations. Controller 2 establishes a Modbus or BACnet data communication link with the unit monitoring system built into the outdoor unit 1 via an IoT communication module, reads the real-time operating power of the compressor at a preset polling cycle, and uses the sliding average value of the read value as... It participates in energy saving estimation, thus adapting to different models of air conditioning units without manual intervention. Controller 2 calculates the energy saving increment in each execution cycle. The accumulated energy savings are then added to the cumulative energy-saving register. Controller 2 formats this accumulated energy savings into an intuitive string of information ("12.48 kWh saved today") for the IoT communication module to read and upload.

[0064] In one embodiment, during actual operation of communication base station B, the rated power of the air conditioner compressor is... For an 8kW power supply, if the inlet dry-bulb temperature Td1 is 38.5°C and the outlet dry-bulb temperature Td2 is 32.5°C during a certain high-temperature period, then the actual temperature drop is... The temperature is 6.0°C. Taking k = 0.025 / °C, real-time power saving is achieved. =1.2kW. If this operating condition continues for 10 hours, the cumulative energy saving is 1.2kW × 10h = 12kWh.

[0065] The above-mentioned preset efficiency threshold =0.70、 0.85 and target efficiency The value of 0.80 was obtained through calibration tests conducted on this device in a standard enthalpy difference laboratory. Test data shows that, under nominal airflow conditions, when the evaporative cooling efficiency... When the water distribution reaches 0.85, there are no obvious macroscopic dry spots on the outlet side surface of the wet film 5. Further increasing the water distribution will result in a less than 0.3°C decrease in outlet temperature, leading to diminishing economic benefits. When the temperature drops below 0.70, the outlet dry bulb temperature Td2 rises by more than 1.0°C compared to the fully wetted state, and the cooling effect is significantly reduced. Based on the above experimental calibration, Set to 0.85 Set to 0.70. Setting it to 0.80 achieves the optimal balance between cooling effect and water consumption.

[0066] To facilitate the execution of instructions from the control and calculation module, a water pump 3 electrically connected to the water pump control unit is also included. The inlet of the water pump 3 is connected to an open water tank 4 located at the bottom of the wet membrane 5, and the outlet of the water pump 3 is connected to a water pipe 7 located inside the frame of the wet membrane 5. Several downward-facing water distribution holes are provided on the upper part of the water pipe 7, through which water flows to wet the wet membrane 5. An inlet is provided on the side wall of the water tank 4, connected to an external water source via a tap water supply pipe. A float valve 6 is provided inside the water tank 4 to automatically control the water supply operation of the tap water supply pipe according to changes in the liquid level, maintaining a stable water level in the water tank 4. Near the edge of the water tank 4, an inwardly protruding support edge is provided, on which the lower edge of the wet membrane 5 frame rests directly, enabling quick assembly and disassembly without tools.

[0067] The IoT communication module is physically integrated with controller 2 within the same electrical control box, which is mounted on the side wall of the pre-cooling device's outer casing. It is electrically connected to controller 2 via a serial communication interface and establishes a data link with an external network via a 4G / 5G cellular antenna or Ethernet interface. It receives energy-saving data output from the control calculation module and is responsible for uploading it to a remote server or user terminal. This energy-saving data includes at least the accumulated energy savings updated and stored in controller 2's memory by the energy-saving estimation unit during each execution cycle. At the end of each preset execution cycle, controller 2 actively reads this accumulated energy savings value from memory and packages it together with real-time temperature data obtained from the data acquisition module.

[0068] In one specific embodiment, the communication hardware unit of the IoT communication module is a 4G / 5G cellular communication module, specifically a 4G LTE communication module based on the Qualcomm MDM9x07 chipset. This module supports the LTE Cat.4 standard, with an uplink speed of up to 50Mbps and a downlink speed of up to 150Mbps, and its operating frequency bands cover Band 1 / 3 / 5 / 8 / 38 / 39 / 40 / 41 used by domestic operators. It connects to the corresponding pins of the controller 2 via a UART serial interface, operating at a 3.3V TTL level. The communication hardware unit has a built-in TCP / IP protocol stack and MQTT client functionality, allowing the controller 2 to perform network attachment, socket connection establishment, and data transmission and reception simply through AT commands.

[0069] In another optional implementation, when the deployment site has wired network conditions, the communication hardware unit is an Ethernet communication module, specifically a hardware TCP / IP Ethernet controller based on the W5500 chip. This chip integrates a 10 / 100M adaptive Ethernet physical layer transceiver and communicates with controller 2 through an SPI serial interface.

[0070] In another optional implementation, the communication hardware unit is a Wi-Fi communication module, specifically a Wi-Fi module based on the ESP8266 chip, which supports the 802.11 b / g / n standard, operates in the 2.4GHz frequency band, and is connected to the controller 2 via a UART interface.

[0071] At the end of each preset execution cycle, controller 2 organizes the energy-saving related data generated by the control calculation module into a preset data frame format, the field contents of which are shown in Table 3 below:

[0072] Table 3

[0073]

[0074] Controller 2 sends the aforementioned data frames to the receiving buffer of the IoT communication module via its serial communication interface. Further, a network connection is established based on a preset target address. In the implementation using a 4G / 5G cellular communication module, the target address is the public IP address or domain name of the cloud server, and the communication protocol is MQTT. Controller 2 sends an AT command sequence to the communication hardware unit, and the IoT communication module encapsulates the data to be uploaded in JSON format. In the implementation using an Ethernet or Wi-Fi module, data transmission can use the HTTP protocol. Controller 2 initiates an HTTP POST request to the cloud server through the communication hardware unit, with the request body also containing the aforementioned JSON format data.

[0075] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0076] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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. An intelligent pre-cooling device, comprising a wet film (5) installed on the air inlet side of an outdoor air conditioning unit (1), a water supply assembly, and a controller (2), characterized in that, Also includes: Data acquisition module: used to acquire air thermal and humidity state parameters characterizing the precooling process of wet film (5), including at least a sensing unit for acquiring inlet dry bulb temperature Td1, inlet wet bulb temperature Twb and outlet dry bulb temperature Td2; Control and calculation module: used to generate water pump control commands and calculate energy savings based on the air temperature and humidity parameters, and its execution unit includes at least: Efficiency calculation unit, used to calculate according to formula Real-time calculation of the actual evaporative cooling efficiency of the wet film (5) And when detected Water supply will be forcibly stopped when the water level is below a preset threshold. The water pump control unit is used to calculate the actual evaporative cooling efficiency. Compared with the preset target efficiency Compare and based on the deviation A proportional-integral (PI) control algorithm is used to generate a pump control signal for adjusting the wet film wetting state to continuously regulate the water supply flow rate of the water supply component. The PI control algorithm has a proportional coefficient Kp = 5.0 and an integral coefficient Ki = 0.2, and maintains the current control signal unchanged when |e| < 0.

02. The preset target efficiency... The value range is 0.75 to 0.

85.

2. The intelligent precooling device according to claim 1, characterized in that: The water supply assembly includes a water tank (4) installed at the bottom of the air inlet side of the outdoor unit (1) of the air conditioner. The water tank (4) has a support edge near its edge, and a wet film frame is placed on the support edge. The wet film (5) is placed inside the wet film frame. A water pump (3) and a float valve (6) are installed inside the water tank (4). A water pipe (7) is installed at the outlet of the water pump (3). A downward-facing hole is opened on the water pipe (7), and water can flow down from the hole to wet the wet film (5). A controller (2) is provided on the wet film frame.

3. The intelligent precooling device according to claim 1, characterized in that: The data acquisition module includes a temperature sensor for obtaining the wet-bulb temperature of the incoming air, comprising a temperature sensing probe and an absorbent cotton gauze sleeve wrapped around the probe. The lower end of the cotton gauze sleeve is immersed in a water replenishment container, and the probe surface is kept moist through capillary action.

4. The intelligent precooling device according to claim 1, characterized in that: The efficiency calculation unit includes: defining the theoretical maximum cooling capacity. This is the difference between the inlet dry-bulb temperature Td1 and the inlet wet-bulb temperature Twb. when When the temperature is <2℃, it is judged as a high humidity condition and a water pump stop signal is generated directly to force the water pump to shut down (3).

5. The intelligent precooling device according to claim 1, characterized in that: The water pump control unit also includes a start-up threshold. and stopping threshold And satisfy ; Among them, the start threshold The stop threshold is determined based on the evaporative cooling efficiency calibration value when the outlet air temperature rises above a preset value compared to the fully humidified state. The evaporative cooling efficiency calibration value is determined based on the absence of obvious macroscopic dry spots on the outlet side of the wet film.

6. The intelligent precooling device according to claim 1, characterized in that: When the absolute value of the deviation e exceeds the preset dead zone range, the water pump control unit generates a pulse width modulation signal duty cycle based on the proportional coefficient Kp and the integral coefficient Ki. ; When the absolute value of the deviation e is within the preset dead zone range, the duty cycle of the current pulse width modulation signal remains unchanged.

7. The intelligent precooling device according to claim 1, characterized in that: The control and calculation module also includes an energy-saving estimation unit, which is used to calculate the power saving achieved by pre-cooling operation in real time based on the actual cooling range and the pre-stored correspondence between condensing temperature and compressor power consumption.

8. The intelligent precooling device according to claim 7, characterized in that: The energy-saving estimation unit stores a configurable coefficient k as the relationship between condensing temperature and compressor power consumption, and the controller obtains the rated power of the air conditioner compressor. include: Receives the rated power value manually input via the configuration interface; or The IoT communication module establishes data communication with the air conditioning unit's monitoring system to read the compressor's real-time operating power at preset intervals, and uses the sliding average of the read values ​​as the rated power. .

9. The intelligent precooling device according to claim 1, characterized in that, Also includes: The Internet of Things (IoT) communication module is used to receive energy-saving related data output by the control and calculation module, and upload the energy-saving related data to a remote server or user terminal. Among them, energy-saving related data include at least one of the following: inlet dry bulb temperature, wet bulb temperature, outlet dry bulb temperature, evaporative cooling efficiency of wet film (5), real-time power saving and cumulative power saving.

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