Intelligent control method for outdoor ec fan of machine room air conditioner

Abstract

This invention relates to the field of data center air conditioning control technology, and particularly to an intelligent control method for outdoor EC fans in data center air conditioning systems. This method solves the problem in existing technologies where premature start-up of EC fans in low-temperature environments leads to insufficient high-pressure build-up and refrigerant backflow, triggering low-pressure alarms and shutdowns. The intelligent control method for outdoor EC fans in data center air conditioning systems includes adding an ambient temperature probe, a high-pressure sensor, and an exhaust temperature probe to the data center air conditioning system. The system collects and stores the current ambient temperature T1, high-pressure value P, and exhaust temperature value T2 in real time in the controller. This invention effectively avoids low-pressure alarms caused by premature start-up of EC fans in low-temperature environments through differentiated temperature zone control, while simultaneously solving the high-pressure alarm problem in high-temperature environments, ensuring stable operation of the data center air conditioning system throughout the year.

Description

Technical Field

[0001] This invention relates to the field of computer room air conditioning control technology, and in particular to an intelligent control method for an outdoor EC fan of a computer room air conditioner. Background Technology

[0002] With the rapid development of the data center industry, data center air conditioning, as a critical infrastructure ensuring the normal operation of core IT equipment such as servers, storage devices, and network switching equipment, is receiving increasing attention from the industry regarding its stability, reliability, and energy efficiency. In the outdoor condensing units of data center air conditioning systems, the fan plays a crucial role in forcibly cooling the high-temperature, high-pressure gaseous refrigerant discharged from the compressor. Its performance directly determines the condensing efficiency and overall operational safety of the cooling system. In recent years, EC fans (electronically commutated DC fans) have gradually replaced traditional AC asynchronous fans, becoming the mainstream development direction for fan technology due to their significant advantages such as high efficiency and energy saving, stepless smooth speed regulation within a 10% to 100% speed range, low operating noise, precise speed control, long service life, and minimal maintenance. In the field of data center air conditioning, replacing traditional AC fans in outdoor condensers with EC fans can not only significantly reduce the overall energy consumption of the air conditioning system but also significantly improve the noise environment of the data center and enhance its green energy-saving level.

[0003] EC fans require an 8-10 second build-up time from receiving a start command to reaching their minimum effective operating speed. This inherent start-up delay poses a significant challenge to their application in data center air conditioning systems. In high-temperature summer environments, when the ambient temperature reaches 35°C or higher, the high-pressure side pressure of the system rises rapidly within a very short time after the compressor starts. According to the existing conventional scheme of controlling EC fan start-up and shutdown based on high-pressure, the EC fan only starts when the high-pressure rises to the EC fan's start-up pressure threshold. However, at this time, the EC fan is still in the build-up phase and has not yet reached the minimum speed required for effective heat dissipation. The high-pressure has already rapidly exceeded the system's high-pressure alarm value, causing the air conditioning to trigger high-pressure protection and shut down, severely impacting the continuity of cooling in the data center and the safe operation of IT equipment. To solve this problem, existing technologies propose an improved scheme that allows the EC fan to start before the compressor starts. This involves predicting the rising trend of the high-pressure based on the ambient temperature and starting the EC fan in advance so that it reaches its effective speed when the compressor starts, thereby avoiding high-temperature and high-pressure alarms.

[0004] However, while this improvement scheme achieved some success in high-temperature summer environments, it revealed new and serious problems in low-temperature winter environments: when the ambient temperature is below 15°C or even lower, if the EC fan continues to operate according to the early start-up strategy, the excessive heat dissipation capacity of the condenser due to the low ambient temperature prevents the high-pressure side pressure from reaching the level required for normal operation. This prevents the refrigerant from smoothly returning to the indoor evaporator, resulting in persistently low low-pressure side pressure, ultimately triggering low-pressure protection and shutdown. The existing conventional scheme of controlling the EC fan speed based on high-pressure lacks comprehensive awareness of ambient temperature and cannot adaptively adjust the EC fan's start-up timing and speed strategy according to seasonal changes and ambient temperature differences. It always uses a single control logic, thus failing to fundamentally solve the problems of both high-temperature / high-pressure alarms and low-temperature / low-pressure alarms. Summary of the Invention

[0005] The purpose of this invention is to provide an intelligent control method for the outdoor EC fan of a computer room air conditioner. This method solves the problem in the prior art where, when the ambient temperature is below 15°C or even lower, if the EC fan still operates according to the strategy of starting up in advance, the high-pressure side pressure of the system cannot be established to the level required for normal operation due to the excessive heat dissipation capacity of the condenser caused by the low ambient temperature. As a result, the refrigerant cannot flow back to the indoor evaporator smoothly, and the low-pressure side pressure of the system remains low, eventually triggering the low-pressure protection and shutting down the system.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A smart control method for an outdoor EC fan of a computer room air conditioner includes adding an ambient temperature probe, a high pressure sensor, and an exhaust temperature probe to the computer room air conditioner system. The ambient temperature probe, high pressure sensor, and exhaust temperature probe collect the current ambient temperature T1, high pressure value P, and exhaust temperature value T2 in real time, and store the collected data in the controller. When the computer room air conditioner receives a start command and needs to run in cooling mode, the controller makes a comprehensive judgment based on the current ambient temperature T1 and the average value of the highest high pressure P and the average value of the highest exhaust temperature T2 of the previous 10 compressor runs. The controller divides the current ambient temperature into three control zones: high temperature zone, transition zone, and low temperature zone. The controller then executes the corresponding EC fan start and speed control strategy according to the determined control zone. When the ambient temperature T1 is greater than or equal to the high temperature boundary temperature, the outdoor EC fan will start in advance before the compressor starts. The advance start time is determined by comprehensive calculation based on the ambient temperature, high pressure and exhaust temperature. After the compressor starts, the outdoor EC fan will adjust its speed in real time according to the high pressure. When the ambient temperature T1 is in the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time, and then adjust the speed according to the high pressure. When the ambient temperature T1 is lower than the low temperature boundary temperature, the compressor starts running first, and then the outdoor EC fan adjusts the speed according to the high pressure.

[0007] Preferably, the high-temperature boundary temperature is set to 32℃. When the ambient temperature T1 ≥ 32℃, the outdoor EC fan starts in advance before the compressor starts. The advance start time S is determined by the weighting coefficients of ambient temperature, high pressure, and exhaust temperature, with ambient temperature having the largest weight, followed by high pressure, and exhaust temperature having the smallest weight. The controller controls the outdoor EC fan to start in advance according to the advance start time S, so that the outdoor EC fan reaches the minimum operating speed before the compressor starts. The default value of the advance start time S is 10 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 32℃, the ratio of the average of the previous 10 highest high pressures P to 28 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 80℃. The higher the ambient temperature, the higher the high pressure, and the higher the exhaust temperature, the longer the advance start time. After the compressor starts running, the controller controls the speed of the outdoor EC fan according to the real-time high pressure value. The speed increases when the high pressure increases and decreases when the high pressure decreases.

[0008] Preferably, the transition range is 25℃ ≤ T1 < 32℃, where 25℃ is the medium-temperature boundary temperature. When the ambient temperature T1 is within the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time. The default value of the preset time is 8 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 25℃, the ratio of the average of the previous 10 highest high-pressure values ​​P to 25 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 70℃. The higher the ambient temperature, the higher the high-pressure value, and the higher the exhaust temperature, the longer the simultaneous start-up and operation time. During the preset time, the outdoor EC fan maintains the lowest speed. After the preset time ends, the controller controls the speed of the outdoor EC fan according to the real-time high-pressure value. The speed increases when the high-pressure value increases and decreases when the high-pressure value decreases, thereby stabilizing the system high-pressure within a safe range and avoiding the occurrence of high-pressure alarms and low-pressure alarms.

[0009] Preferably, the low-temperature boundary temperature is set to 25°C. When the ambient temperature T1 < 25°C, the compressor starts running first, and the outdoor EC fan starts and adjusts its speed according to the high-pressure value after the compressor starts. In low-temperature environments, if the outdoor EC fan starts before the compressor due to the low ambient temperature, the high-pressure cannot be established in time, and the refrigerant cannot flow back to the indoor unit, thus triggering a low-pressure alarm. Therefore, in the low-temperature range, the controller controls the compressor to start first. After the compressor starts running, the controller controls the outdoor EC fan to start and run at the corresponding speed according to the real-time high-pressure value. When the high-pressure increases, the EC fan speed increases; when the high-pressure decreases, the EC fan speed decreases, thereby ensuring that the system will not trigger a low-pressure alarm in low-temperature environments and ensuring the stable operation of the refrigeration system.

[0010] Preferably, the controller stores a historical operation database, which records the highest high-pressure value and the highest exhaust temperature value during the previous 10 compressor operations, and automatically calculates their average value as a reference parameter for the current control strategy. After each compressor operation, the controller automatically updates the data in the historical operation database, enters the highest high-pressure value and the highest exhaust temperature value of the current operation, and removes the earliest record, always maintaining the operation data of the most recent 10 operations. Through this rolling update mechanism, the controller can dynamically adjust the early start time or simultaneous start time of the EC fan according to the recent actual operating conditions of the system, so that the control strategy can adapt to changes in system operating conditions and improve the accuracy and reliability of control.

[0011] Preferably, the outdoor EC fan is a stepless speed-regulating EC fan, capable of stepless smooth speed regulation within a speed range of 10% to 100%. During the normal operation phase after the compressor starts running, the controller uses the high-pressure value as the primary control target, collecting data from the high-pressure sensor in real time. When the high-pressure value rises and exceeds the set high-pressure threshold, the controller proportionally increases the speed of the outdoor EC fan to increase the heat dissipation of the condenser, causing the high-pressure to drop. When the high-pressure value decreases and falls below the set low-pressure threshold, the controller proportionally decreases the speed of the outdoor EC fan to reduce the heat dissipation of the condenser, causing the high-pressure to rise again. Through this closed-loop feedback control method, the system's high-pressure is always maintained within the safe operating range, while fully leveraging the advantages of the EC fan: high efficiency, low noise, stable operation, and long lifespan.

[0012] Preferably, the control method further includes a fault protection mechanism: when an outdoor EC fan experiences abnormal conditions such as overpressure, overcurrent, overheating, or stall during startup, the built-in protection module of the EC fan automatically triggers protection action. After receiving the protection signal, the controller immediately adjusts the control strategy. If the fault can be recovered, the EC fan is restarted; if the fault cannot be recovered, the controller issues a fault alarm and shuts down for protection. Simultaneously, when the system high pressure exceeds the high pressure alarm value or falls below the low pressure alarm value, the controller executes the corresponding emergency strategy according to the current control range: in the high temperature range, the EC fan is started earlier and runs at maximum speed; in the transition range, the simultaneous start-up and operation time is extended; and in the low temperature range, the EC fan speed is reduced to reduce refrigerant loss, thereby minimizing the risk of system shutdown due to high pressure or low pressure alarms and ensuring the continuous and stable operation of the computer room air conditioner.

[0013] The present invention has the following beneficial effects: The intelligent control method for outdoor EC fans of computer room air conditioners provided by this invention achieves the following effects: First, it solves the problem of high-pressure alarms easily occurring when using EC fans in outdoor computer room air conditioners at high ambient temperatures. By enabling the EC fan to start earlier in the high-temperature range and calculating the advance time based on ambient temperature, high pressure, and exhaust temperature, it ensures that the EC fan has reached its effective speed when the compressor starts, fundamentally avoiding high-pressure alarms caused by EC fan start-up delays, and significantly improving the operational reliability and safety of computer room air conditioners in high-temperature environments during summer. Second, it also ensures that low-pressure alarms will not occur at low ambient temperatures. By changing the control strategy in the low-temperature range, the compressor starts running first, and then the EC fan adjusts its speed according to the high pressure, avoiding low-pressure alarms caused by the EC fan starting earlier and the inability to establish high pressure. This allows the computer room air conditioner to operate stably even in low-temperature environments during winter. Third, this control method is highly intelligent and adaptable. By adding an ambient temperature probe and combining it with historical operating data for comprehensive judgment, the control strategy is divided into three intervals: high temperature, transitional season, and low temperature, and handled separately. It can maintain good performance in high-temperature summer, transitional season, or low-temperature winter environments, meeting the differentiated needs of data centers in different regions and improving the overall operational stability and security of the computer room air conditioning system. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the control flow of the present invention. Detailed Implementation

[0016] 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 and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0017] Example 1 Please see Figure 1 As shown in this embodiment, an intelligent control method for an outdoor EC fan of a computer room air conditioner includes adding an ambient temperature probe, a high pressure sensor, and an exhaust temperature probe to the computer room air conditioning system. The ambient temperature probe, the high pressure sensor, and the exhaust temperature probe collect the current ambient temperature T1, the high pressure value P, and the exhaust temperature value T2 in real time, and store the collected data in the controller. When the computer room air conditioner receives a start command and needs to run in cooling mode, the controller makes a comprehensive judgment based on the current ambient temperature T1 and the average value of the highest high pressure P and the average value of the highest exhaust temperature T2 of the previous 10 compressor runs. The controller divides the current ambient temperature into three control zones: high temperature zone, transition zone, and low temperature zone. Based on the determined control zone, the controller executes the corresponding EC fan start and speed control strategy. When the ambient temperature T1 is greater than or equal to the high temperature boundary temperature, the outdoor EC fan will start in advance before the compressor starts. The advance start time is determined by comprehensive calculation based on the ambient temperature, high pressure and exhaust temperature. After the compressor starts, the outdoor EC fan will adjust its speed in real time according to the high pressure. When the ambient temperature T1 is in the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time, and then adjust the speed according to the high pressure. When the ambient temperature T1 is lower than the low temperature boundary temperature, the compressor starts running first, and then the outdoor EC fan adjusts the speed according to the high pressure.

[0018] In this embodiment, the current ambient temperature is assumed to be 38℃, which is within the high-temperature range. When the computer room air conditioner receives the start-up command and determines that cooling is required, the controller first reads the current ambient temperature T1=38℃ collected by the ambient temperature probe, and simultaneously retrieves the average highest high-pressure value P and the average highest exhaust temperature T2 from the historical operation database for the previous 10 compressor runs. Assume P=26 bar and T2=85℃. The controller calculates the EC fan early start time S according to the comprehensive judgment formula: ambient temperature accounts for 70%, i.e., 7×(38 / 32)≈8.3 seconds; high-pressure value accounts for 20%, i.e., 2×(26 / 28)≈1.9 seconds; exhaust temperature accounts for 10%, i.e., 1×(85 / 80)≈1.1 seconds. The comprehensive early start time is approximately 10 seconds (taking the upper limit of the default value). Based on this, the controller controls the outdoor EC fan to start 10 seconds before the compressor starts, so that the EC fan has reached the minimum operating speed when the compressor starts. Ten seconds later, the compressor starts running. At this point, the high pressure has not yet climbed to the alarm value because the EC fan is effectively dissipating heat. After the compressor starts, the controller controls the EC fan speed according to the real-time high pressure value: the speed increases when the high pressure increases and decreases when the high pressure decreases, thus ensuring stable system operation and preventing high pressure alarms. This embodiment fully verifies that in high-temperature environments, a pre-start strategy can effectively avoid high pressure alarm problems.

[0019] Example 2 Please see Figure 1 As shown in this embodiment, an intelligent control method for an outdoor EC fan of a computer room air conditioner is implemented. The high-temperature threshold temperature is set to 32℃. When the ambient temperature T1 ≥ 32℃, the outdoor EC fan starts before the compressor starts. The advance start time S is determined by the weighting coefficients of ambient temperature, high pressure, and exhaust temperature, with ambient temperature having the largest weight, followed by high pressure, and exhaust temperature having the smallest weight. The controller controls the outdoor EC fan to start in advance according to the advance start time S, so that the outdoor EC fan reaches the minimum operating speed before the compressor starts. The default value of the advance start time S is 10 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 32℃, the ratio of the average of the previous 10 highest high pressure values ​​P to 28 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 80℃. The higher the ambient temperature, the higher the high pressure, and the higher the exhaust temperature, the longer the advance start time. After the compressor starts running, the controller controls the speed of the outdoor EC fan according to the real-time high pressure value. The speed increases when the high pressure increases and decreases when the high pressure decreases.

[0020] The low-temperature threshold temperature is set at 25℃. When the ambient temperature T1 < 25℃, the compressor starts running first. The outdoor EC fan starts and adjusts its speed according to the high-pressure value after the compressor starts. In low-temperature environments, if the outdoor EC fan starts before the compressor due to the low ambient temperature, the high-pressure cannot be established in time, and the refrigerant cannot flow back to the indoor unit, thus triggering a low-pressure alarm. Therefore, in the low-temperature range, the controller controls the compressor to start first. After the compressor starts running, the controller controls the outdoor EC fan to start and run at the corresponding speed according to the real-time high-pressure value. When the high-pressure increases, the EC fan speed increases; when the high-pressure decreases, the EC fan speed decreases. This ensures that the system will not trigger a low-pressure alarm in low-temperature environments and guarantees the stable operation of the refrigeration system.

[0021] The control method also includes a fault protection mechanism: when an outdoor EC fan experiences abnormal conditions such as overpressure, overcurrent, overheating, or stall during startup, the built-in protection module of the EC fan automatically triggers protection action. After receiving the protection signal, the controller immediately adjusts the control strategy. If the fault can be recovered, the EC fan is restarted; if the fault cannot be recovered, the controller issues a fault alarm and shuts down for protection. At the same time, when the system high pressure exceeds the high pressure alarm value or falls below the low pressure alarm value, the controller executes the corresponding emergency strategy according to the current control range: in the high temperature range, the EC fan is started earlier and runs at maximum speed; in the transition range, the simultaneous start-up time is extended; and in the low temperature range, the EC fan speed is reduced to reduce refrigerant loss, thereby minimizing the risk of system shutdown due to high pressure or low pressure alarms and ensuring the continuous and stable operation of the computer room air conditioning.

[0022] In this embodiment, the current ambient temperature is assumed to be 28°C, which falls within the transition range. When the computer room air conditioner receives a start-up command and determines that cooling operation is required, the controller reads the current ambient temperature T1=28°C and retrieves the average of the highest high-pressure values ​​P=24 bar and the average of the highest exhaust temperatures T2=75°C from the historical operation database. The controller calculates the simultaneous start-up time S based on the comprehensive judgment formula for the transition range: ambient temperature accounts for 62.5%, i.e., 5×(28 / 25)=5.6 seconds; high-pressure value accounts for 25%, i.e., 2×(24 / 25)=1.9 seconds; exhaust temperature accounts for 12.5%, i.e., 1×(75 / 70)≈1.1 seconds. The comprehensive simultaneous start-up time is approximately 8 seconds (taking the default value). Based on this, the controller controls the outdoor EC fan and compressor to start simultaneously and run at the lowest speed for approximately 8 seconds. During these 8 seconds, the EC fan and compressor operate synchronously, and the system gradually establishes a stable high-pressure. Eight seconds later, the controller switches to a control mode that adjusts the EC fan speed in real time based on the high pressure: the speed increases when the high pressure increases and decreases when the high pressure decreases. This embodiment, by simultaneously starting and maintaining the lowest speed for a period of time, avoids both excessive heat dissipation that may result from premature startup in high-temperature zones and insufficient pressure that may result from premature compressor startup in low-temperature zones, achieving optimal control balance during transitional seasons.

[0023] Example 3 Please see Figure 1 As shown in this embodiment, an intelligent control method for an outdoor EC fan of a computer room air conditioner has a transition range of 25℃≤T1<32℃, where 25℃ is the medium-temperature boundary temperature. When the ambient temperature T1 is within the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time. The default value of the preset time is 8 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 25℃, the ratio of the average of the previous 10 highest high-pressure pressures P to 25 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 70℃. The higher the ambient temperature, the higher the high-pressure pressure, and the higher the exhaust temperature, the longer the simultaneous start-up and operation time. During the preset time, the outdoor EC fan maintains the lowest speed. After the preset time ends, the controller controls the speed of the outdoor EC fan according to the real-time high-pressure value. The speed increases when the high-pressure increases and decreases when the high-pressure decreases, thereby stabilizing the system high-pressure within a safe range and avoiding the occurrence of high-pressure alarms and low-pressure alarms.

[0024] The controller stores a historical operation database, which records the highest high-pressure value and highest exhaust temperature value during the previous 10 compressor operations, and automatically calculates their average value as a reference parameter for the current control strategy. After each compressor operation, the controller automatically updates the data in the historical operation database, enters the highest high-pressure value and highest exhaust temperature value of the current operation, and removes the earliest record, always maintaining the data from the most recent 10 operations. Through this rolling update mechanism, the controller can dynamically adjust the early start time or simultaneous start time of the EC fan according to the recent actual operating conditions of the system, enabling the control strategy to adapt to changes in system operating conditions and improve the accuracy and reliability of control.

[0025] The outdoor EC fan is a steplessly variable speed (CVT) EC fan, capable of smooth, stepless speed regulation within a range of 10% to 100%. During normal operation after the compressor starts, the controller uses the high-pressure value as the primary control target, collecting data from the high-pressure sensor in real time. When the high-pressure value rises and exceeds the set high-pressure threshold, the controller proportionally increases the speed of the outdoor EC fan, increasing the heat dissipation of the condenser and causing the high-pressure to drop. When the high-pressure value decreases and falls below the set low-pressure threshold, the controller proportionally decreases the speed of the outdoor EC fan, reducing the heat dissipation of the condenser and causing the high-pressure to rise again. Through this closed-loop feedback control method, the system's high-pressure is always maintained within a safe operating range, while fully leveraging the advantages of the EC fan: high efficiency, low noise, stable operation, and long lifespan.

[0026] In this embodiment, the current ambient temperature is assumed to be 10℃, which is in the low-temperature range. When the computer room air conditioner receives a start-up command and determines that cooling is required, the controller reads the current ambient temperature T1=10℃, confirming that the ambient temperature is below the low-temperature threshold of 25℃. Unlike the high-temperature and transitional ranges, in the low-temperature range, the controller no longer allows the EC fan to start prematurely or simultaneously with the compressor; instead, it controls the compressor to start running first. After the compressor starts, the system begins to build up high pressure. When the high pressure reaches the EC fan start-up condition, the controller controls the outdoor EC fan to start and run at the corresponding speed based on the real-time high pressure value. Since the compressor has already started running and the high pressure has been initially established, the EC fan can effectively cooperate in heat dissipation after starting, avoiding the problem of high pressure not being established and refrigerant not being able to flow back due to the EC fan starting prematurely, thus preventing low-pressure alarms. In subsequent operation, the controller also adjusts the EC fan speed in real time according to the high pressure: the speed increases when the high pressure increases and decreases when the high pressure decreases. This embodiment fully demonstrates that in low-temperature environments, by changing the startup sequence, the low-pressure alarm problem caused by the early start-up of the EC fan in traditional control methods can be effectively solved, ensuring that the computer room air conditioner can operate safely and stably in winter.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A method for intelligent control of an outdoor EC fan for a computer room air conditioner, characterized in that, Includes the following steps: An ambient temperature probe, a high-pressure sensor, and an exhaust temperature probe are added to the computer room air conditioning system. The ambient temperature probe, high-pressure sensor, and exhaust temperature probe collect the current ambient temperature T1, high-pressure value P, and exhaust temperature value T2 in real time, and store the collected data in the controller. When the computer room air conditioner receives a start command and needs to run in cooling mode, the controller makes a comprehensive judgment based on the current ambient temperature T1 and the average value of the highest high pressure P and the average value of the highest exhaust temperature T2 of the previous 10 compressor runs. The controller divides the current ambient temperature into three control zones: high temperature zone, transition zone, and low temperature zone. The controller then executes the corresponding EC fan start and speed control strategy according to the determined control zone. When the ambient temperature T1 is greater than or equal to the high temperature boundary temperature, the outdoor EC fan will start in advance before the compressor starts. The advance start time is determined by comprehensive calculation based on the ambient temperature, high pressure and exhaust temperature. After the compressor starts, the outdoor EC fan will adjust its speed in real time according to the high pressure. When the ambient temperature T1 is in the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time, and then adjust the speed according to the high pressure. When the ambient temperature T1 is lower than the low temperature boundary temperature, the compressor starts running first, and then the outdoor EC fan adjusts the speed according to the high pressure.

2. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 1, characterized in that, The high-temperature threshold temperature is set to 32℃. When the ambient temperature T1 ≥ 32℃, the outdoor EC fan starts before the compressor starts. The advance start time S is determined by the weighting coefficients of ambient temperature, high pressure, and exhaust temperature, with ambient temperature having the largest weight, followed by high pressure, and exhaust temperature having the smallest weight. The controller controls the outdoor EC fan to start in advance according to the advance start time S, so that the outdoor EC fan reaches the minimum operating speed before the compressor starts. The default value of the advance start time S is 10 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 32℃, the ratio of the average of the previous 10 highest high pressure values ​​P to 28 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 80℃. The higher the ambient temperature, the higher the high pressure, and the higher the exhaust temperature, the longer the advance start time. After the compressor starts running, the controller controls the speed of the outdoor EC fan according to the real-time high pressure value. The speed increases when the high pressure increases and decreases when the high pressure decreases.

3. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 1, characterized in that, The transition range is 25℃ ≤ T1 < 32℃, where 25℃ is the medium-temperature boundary temperature. When the ambient temperature T1 is within the transition range, the outdoor EC fan and compressor start simultaneously and run at the lowest speed for a preset time. The default value of the preset time is 8 seconds, and it can be dynamically adjusted according to the ratio of the current ambient temperature T1 to 25℃, the ratio of the average of the previous 10 highest high-pressure values ​​P to 25 bar, and the ratio of the average of the previous 10 highest exhaust temperatures T2 to 70℃. The higher the ambient temperature, the higher the high-pressure value, and the higher the exhaust temperature, the longer the simultaneous start-up and operation time will be. During the preset time, the outdoor EC fan maintains the lowest speed. After the preset time ends, the controller controls the speed of the outdoor EC fan according to the real-time high-pressure value. The speed increases when the high-pressure value increases and decreases when the high-pressure value decreases, thereby stabilizing the system high-pressure value within a safe range and avoiding the occurrence of high-pressure alarms and low-pressure alarms.

4. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 2, characterized in that, The low-temperature boundary temperature is set to 25℃. When the ambient temperature T1 < 25℃, the compressor starts running first. The outdoor EC fan starts and adjusts its speed according to the high pressure value after the compressor starts. In a low-temperature environment, if the outdoor EC fan starts before the compressor due to the low ambient temperature, the high pressure cannot be established in time, and the refrigerant cannot flow back to the indoor unit, thus triggering a low-pressure alarm. Therefore, in the low-temperature range, the controller prioritizes the start of the compressor. After the compressor starts running, the controller starts the outdoor EC fan according to the real-time high pressure value and operates at the corresponding speed. When the high pressure increases, the speed of the EC fan increases, and when the high pressure decreases, the speed of the EC fan decreases, thereby ensuring that the system will not have a low-pressure alarm in the low-temperature environment, while ensuring the stable operation of the refrigeration system.

5. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 3, characterized in that, The controller stores a historical operation database, which records the highest high pressure value and the highest exhaust temperature value during the previous 10 compressor operations, and automatically calculates their average value as a reference parameter for the current control strategy. After each compressor operation, the controller automatically updates the data in the historical operation database, recording the highest high-pressure value and the highest exhaust temperature value of the current operation, and removing the earliest record, always maintaining the operation data of the most recent 10 times. Through this rolling update mechanism, the controller can dynamically adjust the early start time or simultaneous start time of the EC fan according to the recent actual operating conditions of the system, so that the control strategy can adapt to changes in system operating conditions and improve the accuracy and reliability of control.

6. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 5, characterized in that, The outdoor EC fan is a steplessly variable speed EC fan, capable of smooth stepless speed regulation within a range of 10% to 100%. During the normal operation phase after the compressor starts running, the controller uses the high-pressure value as the primary control target, collecting data from the high-pressure sensor in real time. When the high-pressure value rises and exceeds the set high-pressure threshold, the controller proportionally increases the speed of the outdoor EC fan, increasing the heat dissipation of the condenser and causing the high-pressure to drop. When the high-pressure value decreases and falls below the set low-pressure threshold, the controller proportionally decreases the speed of the outdoor EC fan, reducing the heat dissipation of the condenser and causing the high-pressure to rise again. Through this closed-loop feedback control method, the system's high-pressure is always maintained within the safe operating range, while fully leveraging the advantages of the EC fan: high efficiency, low noise, stable operation, and long lifespan.

7. The intelligent control method for an outdoor EC fan of a computer room air conditioner according to claim 4, characterized in that, The control method also includes a fault protection mechanism: when an outdoor EC fan experiences abnormal conditions such as overpressure, overcurrent, overheating, or stall during startup, the built-in protection module of the EC fan automatically triggers protection action. After receiving the protection signal, the controller immediately adjusts the control strategy. If the fault can be recovered, the EC fan is restarted; if the fault cannot be recovered, the controller issues a fault alarm and shuts down for protection. At the same time, when the system high pressure exceeds the high pressure alarm value or falls below the low pressure alarm value, the controller executes the corresponding emergency strategy according to the current control range: in the high temperature range, the EC fan is started earlier and runs at maximum speed; in the transition range, the simultaneous start-up and operation time is extended; and in the low temperature range, the EC fan speed is reduced to reduce refrigerant loss, thereby minimizing the risk of system shutdown due to high pressure or low pressure alarms and ensuring the continuous and stable operation of the computer room air conditioning.

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