A control method for fresh air air conditioning integrated machine

Abstract

The present invention relates to the field of fresh air heat exchange technology, and in particular to a control method for a fresh air air conditioner integrated machine: a single or multiple integrated machines are installed indoors, temperature sensors are installed indoors and outdoors, and the control of the fresh air, the air conditioner evaporator and all the temperature sensors is realized by a centralized controller. o is the outdoor temperature, T il is the required limit of indoor temperature, such as T o ≤T il ‑2973P / (V·x), turn on fresh air but not air conditioning, such as T il ‑2973P / (V·x)<T o ≤T il , turn on fresh air and air conditioning at the same time, such as T o >T il The present invention maximizes the use of outdoor cold air while using the air outside the air conditioner evaporator for supplementary cooling, thereby achieving the purpose of fully utilizing the natural cold source and achieving indoor cooling with minimal energy consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of fresh air heat exchange, and in particular to a control method for a fresh air air conditioner integrated machine. Background Art

[0002] Computer rooms and other places with dense heat-generating equipment require a relatively low and stable indoor temperature. Air conditioning is still the main method for controlling the temperature of computer rooms. However, air conditioning consumes a lot of energy. According to statistics, air conditioning energy consumption can account for one-third of the total energy consumption of the entire computer room.

[0003] In most areas of my country, the outdoor air temperature is low most of the time in seasons other than summer and even in summer nights. Using natural cooling sources such as outdoor fresh air to cool the computer room can significantly reduce electricity costs. However, the outdoor air temperature is constantly changing, and a device and control method are needed to maximize the use of these natural cooling sources. Summary of the invention

[0004] Since the outdoor temperature varies with the season and time, a device and a corresponding control method are needed to maximize the use of low-temperature air. To address this problem, the present invention provides a control method for a fresh air air-conditioning integrated machine. The integrated machine used in the present invention has the following components and structures, including a main unit arranged indoors and an air inlet pipe connecting the main unit with the outdoors. The main unit is provided with an indoor air inlet, an air inlet cavity, an air filter, an air conditioner evaporator and its components, a power fan and an air outlet. The air inlet pipe is connected to the air inlet cavity. Driven by the power fan, outdoor air enters the air inlet cavity through the air inlet pipe and flows through the air filter, evaporator, and power fan in sequence, and then is blown into the room through the air outlet.

[0005] The present invention uses the above-mentioned integrated device to realize the control of fresh air and air conditioning functions, and the steps are as follows:

[0006] According to the design, install a single or several integrated devices at different locations indoors, and install temperature sensors indoors and outdoors respectively;

[0007] 2. The fresh air function of the all-in-one machine, the air conditioner evaporator and all temperature sensors are all controlled by a centralized controller;

[0008] 3. After the all-in-one machine is working, if the outdoor temperature T o ≤T il -2973P / (V·x), open the fresh air function without opening the air conditioner evaporator, if T il -2973P / (V·x)<T o ≤T il , open the fresh air and the air conditioner evaporator at the same time, and the air conditioner will provide cooling for the fresh air. If T o >T il, turn off the fresh air function and only turn on the air conditioner evaporator for internal circulation cooling, where T o is the outdoor temperature, T il is the required limit of indoor temperature, P is the total power of indoor electrical equipment, V is the air volume of a single integrated machine, and x is the number of integrated machines.

[0009] Outdoor critical temperature T o =T il The derivation process of the -2973P / (V·x) formula is as follows:

[0010] 1. According to the calculation formula of absorbed heat Q = cm△t → P = cm△t → P = cm(T il -T o );

[0011] Where Q is the indoor cooling load, kW; c is the specific heat capacity of air, which is 1.005 kJ / (kg·K); m is the total mass flow rate of air delivered to the room by the integrated unit, kg / s; T o is the outdoor temperature, ℃; T il is the required limit of indoor temperature, ℃; △t is the required limit of indoor temperature - outdoor temperature, that is, T il -T o .

[0012] 2. P = cm(T il -T o )→P=c(V·x)ρ(T il -T o ) / 3600;

[0013] V is the air volume of a single all-in-one machine, m³ / h; ρ is the air density, which is 1.205kg / m³; because the unit of V is m³ / h, it is necessary to convert the unit to m³ / s first, 1h=3600s, so V / 3600 completes the unit conversion. Because more than one all-in-one machine may be used indoors, assuming that x all-in-one machines are used indoors, the total air volume delivered to the room through the all-in-one machine is V·x / 3600.

[0014] 3. P = c(V x)ρ(T il -T0) / 3600→T o =T il -3600P / (cρVx);

[0015] Substituting c=1.005 and ρ=1.205, we can get the outdoor critical temperature T o =T il -2973P / (V·x).

[0016] When the outdoor temperature T o Less than the critical value T ilWhen the temperature is -2973P / (V·x), the low-temperature outdoor air introduced by the all-in-one unit is sufficient to bear the entire indoor cooling load, and only the fresh air function can be operated without the air conditioner evaporator running.

[0017] There are only two variables in the above formula, P and V. When the air volume V of the integrated machine is the largest and constant, and the total power P of the indoor electrical equipment increases, the outdoor temperature T is required to be o If the total power P of indoor electrical equipment and the air volume V of the integrated machine change at the same time, if T o <T il -2973P / (V·x), there is no need to open the air conditioner evaporator of the integrated unit for supplementary cooling, and only the low-energy fresh air function can be operated.

[0018] The centralized controller is based on the outdoor temperature T o The specific control methods for the integrated machine are as follows:

[0019] When T o ≤T il -2973P / (V 低 x), turn on the fresh air function of the integrated machine and maintain it at V 低 Air volume, without turning on the air conditioner evaporator;

[0020] When T il -2973P / (V 低 ·x)<T o ≤T il -2973P / (V 中 x), maintain the fresh air function of the integrated machine and increase the air volume to V 中 , do not turn on the air conditioner evaporator;

[0021] When T il -2973P / (V 中 ·x)<T o ≤T il -2973P / (V 高 x), maintain the fresh air function of the integrated machine and increase the air volume to V 高 , do not turn on the air conditioner evaporator;

[0022] When T il -2973P / (V 高 ·x)<T o ≤T il When maintaining the fresh air function of the integrated machine V 高 The air volume is increased while the air conditioner evaporator is turned on to provide supplementary cooling for the fresh air;

[0023] When T o >T ilWhen the fresh air function is turned off, the air conditioner evaporator is turned on for internal circulation.

[0024] In the above control process, the centralized controller includes each control state, and each time interval △T affects the indoor temperature T i and the indoor temperature limit T il Perform a comparison and judgment. If T i ≤T il Then maintain the original state, if T i >T il The fresh air function is turned off, and the air conditioner evaporator is turned on to perform internal circulation forced refrigeration and cooling to ensure that the indoor temperature is below the limit. il The value range is 26℃~32℃.

[0025] According to the space size of the integrated machine, in the control method of the present invention, the centralized controller adjusts the indoor temperature T every 10 to 60 minutes. i and the indoor temperature limit T il Make a comparative judgment.

[0026] The method of the present invention not only maximizes the use of outdoor cold air to cool the indoor temperature, but also uses the evaporator of the air conditioner of the integrated machine to supplement the cooling of outdoor air in critical conditions, thereby achieving the purpose of fully utilizing the natural cold source and achieving indoor cooling with minimal energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a control flow chart of the method of the present invention. DETAILED DESCRIPTION

[0028] The present invention is described below in conjunction with examples, which are only used to explain the present invention and are not used to limit the scope of the present invention.

[0029] A control method for a fresh air air conditioner integrated machine, the integrated machine used has the following components and structure: a main unit arranged indoors and an air inlet pipe connecting the main unit with the outdoors, the main unit is provided with an indoor air inlet, an air inlet cavity, an air filter, an air conditioner evaporator and its components, a power fan and an air outlet, the air inlet pipe is connected to the air inlet cavity, and outdoor air enters the air inlet cavity through the air inlet pipe driven by the power fan and then flows through the air filter, the evaporator, the power fan in sequence, and is then blown into the machine room through the air outlet.

[0030] The present invention adopts the above-mentioned integrated device to realize the control method of fresh air and air conditioning functions:

[0031] According to the design, one integrated machine is installed in a Class III machine room. The three air volume levels of the integrated machine are: V 高 =9910m³ / h, V 中=7928m³ / h, V 低 =4955m³ / h, the total power of the switch or server in the computer room is 10kW, and temperature sensors are installed inside and outside the computer room;

[0032] The fresh air function of the all-in-one machine, the evaporator of the air conditioner and all temperature sensors are all controlled by the centralized controller;

[0033] After the integrated machine is working, if the temperature outside the equipment room is T o ≤28-2973P / (V·x), open the fresh air function without opening the air conditioner evaporator, if 28-2973P / (V·x)<T o ≤28: open the fresh air and air conditioner evaporator at the same time, and the air conditioner will provide cooling for the fresh air. o When the temperature is higher than 28, the fresh air function is turned off and only the air conditioning function is turned on for internal circulation cooling. o is the outdoor temperature (°C), 28 is the upper temperature limit of the Class III equipment room (°C), P is the total power of indoor electrical equipment, 10kW, V is the air volume of a single integrated machine, 9910m³ / h, x is the number of integrated machines, and x is 1.

[0034] like Figure 1 As shown, the centralized controller is based on the outdoor temperature T o The specific control methods for the integrated machine are as follows:

[0035] When T o ≤28-2973P / (V 低 ·x), that is, T o ≤28-2973×10 / (4955×1), T o When the temperature is ≤22℃, turn on the fresh air function of the integrated machine and maintain it at V 低 Air volume, without turning on the air conditioner evaporator;

[0036] When 28-2973P / (V 低 ·x)<T o ≤28-2973P / (V 中 x), i.e. 22℃<T o ≤28-2973×10 / (7928×1), 22℃<T o When the temperature is ≤24.25℃, maintain the fresh air function of the integrated machine and increase the air volume to V 中 , do not turn on the air conditioner evaporator;

[0037] When 28-2973P / (V 中 ·x)<T o ≤28-2973P / (V 高 x), i.e. 24.25℃<T o≤28-2973×10 / (9910×1),24.25℃<T o When the temperature is ≤25℃, maintain the fresh air function of the integrated machine and increase the air volume to V 高 , do not turn on the air conditioner evaporator;

[0038] When 28-2973P / (V 高 ·x)<T o ≤28, i.e. 25℃<T o When the temperature is ≤28℃, the fresh air function of the integrated machine is maintained at V 高 The air volume is increased while the air conditioner evaporator is turned on to provide supplementary cooling for the fresh air;

[0039] When T o When the temperature is above 28℃, turn off the fresh air function and turn on the air conditioner evaporator for internal circulation.

[0040] In the above control process, the centralized controller includes each control state, and every 30 minutes, the temperature T in the machine room is i Compare with the upper limit of the room temperature requirement of 28°C. If T i ≤28℃, maintain the original state. If T i When the temperature is above 28℃, the fresh air function is turned off and the air conditioner evaporator is turned on to perform internal circulation forced cooling to ensure that the indoor temperature is below the limit.

[0041] 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 principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for a fresh air air conditioner integrated machine, the integrated machine comprising a host machine arranged indoors and an air inlet pipe connecting the host machine with the outdoors, the host machine being provided with an indoor air inlet, an air inlet cavity, an air filter, an air conditioner evaporator and its components, a power fan and an air outlet, the air inlet pipe being connected to the air inlet cavity, outdoor air enters the air inlet cavity through the air inlet pipe under the drive of the power fan, flows through the air filter, the air conditioner evaporator, the power fan in sequence, and then is blown into the indoor through the air outlet; It is characterized in that The control method of the fresh air air conditioner comprises the following steps:

1. Install a single or several integrated devices at different locations indoors according to the design, and install temperature sensors indoors and outdoors respectively; 2. The fresh air function of the all-in-one machine, the air conditioner evaporator and all temperature sensors are all controlled by a centralized controller; 3. Set up an all-in-one high-end V in the centralized controller 高 , mid-range V 中 and low-range V 低 Three fixed air volume levels, the centralized controller adjusts the air volume according to the outdoor temperature T o The changes in the control of the integrated machine are as follows: When T o ≤T il -2973P / (V 低 x), turn on the fresh air function of the integrated machine and maintain it at V 低 Air volume, without turning on the air conditioner evaporator; When T il -2973P / (V 低 ·x)<T o ≤T il -2973P / (V 中 x), maintain the fresh air function of the integrated machine and increase the air volume to V 中 , do not turn on the air conditioner evaporator; When T il -2973P / (V 中 ·x)<T o ≤T il -2973P / (V 高 x), maintain the fresh air function of the integrated machine and increase the air volume to V 高 , do not turn on the air conditioner evaporator; When T il -2973P / (V 高 ·x)<T o ≤T il When maintaining the fresh air function of the integrated machine V 高 The air volume is increased while the air conditioner evaporator is turned on to provide supplementary cooling for the fresh air; When T o >T il When the fresh air function is turned off, the air conditioner evaporator is turned on for internal circulation; Among them, T o is the outdoor temperature, T il is the required limit of indoor temperature, P is the total power of indoor electrical equipment, and x is the number of integrated devices.

2. The control method of the fresh air air conditioner according to claim 1, characterized in that: T il The value range is 26℃~32℃.

3. The control method of the fresh air air conditioner according to claim 1, characterized in that: The centralized controller adjusts the indoor temperature T every 10 to 60 minutes. i and the indoor temperature limit T il Make a comparative judgment.

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