JP5243094B2 - Rack air conditioning system - Google Patents

Description

  The present invention relates to an air conditioning system, and more particularly to a rack air conditioning system suitable for cooling ICT equipment in an information communication machine room.

In recent years, information communication (ICT) devices are rapidly increasing in speed, capacity, and density. These devices are generally stored in a 19-inch server rack conforming to the US IEA standard and housed in an information communication machine room (data center). Server racks often take in cool air from the front and exhaust from the top or back, and each rack is arranged in a horizontal row in the same direction. A plurality of such rack rows are arranged in the machine room, the intake surfaces and the intake surfaces of adjacent rows, and the exhaust surfaces and the exhaust surfaces are opposed to each other. Here, the passage between the intake surfaces is called cold aisle because cold air is supplied from the double floor. On the other hand, the passage between the exhaust surfaces is called hot aisle because the temperature rises due to exhaust from the rack.
In this case, in the conventional method (ambient air conditioning method) that uniformly air-conditions the entire room only by supplying cold air from the double floor, a local high temperature area is generated in the cold aisle due to uneven distribution of heat from the rack, and information communication equipment・ The problem of high-temperature failure of the equipment occurs. In order to solve such a problem, a technique for installing an air conditioner above a cold aisle for local cooling has been proposed (for example, Patent Document 1).

FIG. 11 shows a rack air conditioning system 100 according to this method. A local air conditioner 102 is installed above a cold aisle 105 formed between server rack rows 104a and 104b in a machine room 101. Thus, each server rack is cooled by the cold air supplied from the ambient air conditioner 107 through the double floor space 106 and the cold air supplied from above by the local air conditioner 102.
On the other hand, there is a system in which local air conditioners are arranged in a row, and in particular, a rack type air conditioner having the same module as a server rack has been put into practical use in order to improve space efficiency. The rack type air conditioner is arranged so that the direction of intake and exhaust is opposite to that of the rack 2, that is, sucks high-temperature exhaust in the hot aisle space and blows out cooling air to the cold aisle side.
JP 2003-166729 A

However, even with the arrangement of the rack type air conditioners, the high temperature area changes with time depending on the usage status of the ICT equipment, so it is difficult to always maintain a uniform temperature environment according to the specified temperature.
Furthermore, since the machine room air conditioner is designed on the premise of unmanned operation control, a poor working environment when a person enters for maintenance work or the like becomes a problem.
The present invention is for solving such a problem, and provides a rack air-conditioning system that establishes a uniform temperature environment and secures a favorable work environment.

The gist of the present invention is as follows. That is, the rack air conditioning system according to the present invention is:
(1) A rack air conditioning system that cools a server rack with one or a plurality of air conditioners including a rack type air conditioner in a room where a cold aisle and a hot aisle are formed by one or a plurality of server rack rows, A plurality of temperature sensors are provided in the cold aisle, and the rack-type air conditioner includes means for selecting and blowing an optimum wind direction pattern based on a calculation value based on a temperature measurement value of the plurality of temperature sensors. It is characterized by comprising.
(2) In the above (1), “a plurality of temperature sensors in the cold aisle” is replaced by “a temperature sensor included in each server device in the server rack”.
Generally, a server device includes a temperature sensor for detecting a failure. Therefore, by inputting the temperature information to the air conditioner, it is possible to change to the cold aisle temperature information.
(3) The one or more air conditioners include a double floor blow-off air conditioner type air conditioner.
By including the ambient air conditioner, even if the operation state (wind direction or the like) of the rack type air conditioner changes, it is possible to operate so as not to exceed the worst temperature upper limit.
(4) One or a plurality of human sensors in the cold aisle, and the rack type air conditioner further includes means for changing a wind direction pattern and / or an air volume based on detection of the human sensors. It is characterized by that.

Moreover, the operation method of the rack air conditioning system according to the present invention is as follows:
(5) An operation method of a rack air conditioning system in which a server rack is cooled by one or a plurality of air conditioners including a rack type air conditioner in a room where a cold aisle and a hot aisle are formed by one or a plurality of server rack rows. In the target rack type air conditioner, the step of measuring the temperature at a plurality of positions in the control target area of the target rack type air conditioner for each wind direction pattern by changing the wind direction pattern, and the temperature dispersion value for each wind direction pattern And a step of operating the target rack type air conditioner with a wind direction pattern that minimizes the temperature dispersion value.
(6) In the above invention, the rack air conditioner further includes a step of controlling the capacity of the target rack type air conditioner so that the temperature at the highest temperature position in the wind direction pattern with the minimum dispersion value becomes a set temperature. How to operate the system.

(7) The target rack type air conditioners are a plurality of grouped rack type air conditioners, and the control target area is a merged area of the control target areas of the plurality of rack type air conditioners, and the merged area Each rack type air conditioner is operated with a wind direction pattern that minimizes the temperature dispersion value.
(8) In the above (7), when one or more of the plurality of rack type air conditioners grouped fails, the remaining normal rack type air conditioners minimize the temperature dispersion value in the merged area. (9) In the rack air conditioning system of (4) above, when the presence sensor detects the presence of a person, the remaining normal rack type air conditioner is operated according to the wind direction pattern. The rack-type air conditioner is operated according to a predetermined wind direction pattern.
In the present invention, the “predetermined wind direction pattern” means a preset wind speed pattern when the operator enters the room. The wind direction pattern has no directivity and the wind speed distribution is flat in any direction. For example, a wind direction pattern or the like in which the cool air is not directly applied to the operator as in the direction is exemplified. The purpose is to improve the working environment in the machine room. (10) In the rack air conditioning system of (4), when the human sensor detects the presence of a person, the set temperature of the rack type air conditioner is changed to a temperature higher than a normal set temperature. To do.

According to each of the above inventions, a uniform temperature environment always conforming to the specified temperature can be maintained.
In a system that controls a plurality of rack-type air conditioners in a coordinated manner, the entire machine room can perform efficient air-conditioning control, which contributes to energy savings.
Further, in the system using the human sensor, it is possible to suppress the cold wind speed that hinders the work, which contributes to the improvement of the working environment of the machine room.

  Hereinafter, an embodiment of a rack type air conditioner according to the present invention will be described in more detail with reference to FIGS. In the drawings, the same components are denoted by the same reference numerals, and redundant description is omitted. Needless to say, the scope of the present invention is described in the claims and is not limited to the following embodiments.

(First embodiment)
FIG. 1 is a diagram showing a cross-sectional configuration of a rack air conditioning system 1 according to an embodiment of the present invention. FIG. 2 is a diagram showing a planar configuration inside the machine room 5. FIG. 3 is a diagram illustrating a control target region R1 of the rack type air conditioner 8a-1. FIG. 4 is a diagram showing a wind direction / temperature control flow of the rack air conditioning system 1.

The air conditioning system 1 is a system that is housed in an information communication machine room 5 and cools the racks 2 constituting the rack row 3 with an air conditioner 4 that is an ambient air conditioner and a rack type air conditioner 8 that is a local air conditioner. .
The air conditioner 4 which is an ambient air conditioner includes an indoor unit 4a having an evaporator 4e and a blower 4c, an outdoor unit 4b mainly composed of a compressor, a condenser (all not shown), and a refrigerant connecting them. A pipe 4d is provided. With this configuration, the cold generated by the refrigeration cycle operation is cooled by exchanging heat with the indoor air introduced into the indoor unit 4a, and supplied to the machine room by the blower 4c.

The interior of the machine room 5 is divided into three spaces by a floor panel 5d and a ceiling panel 5e. A double floor space 5c is formed in the lower part of the floor panel 5d, and a ceiling space 5b is formed in the upper part of the ceiling panel 5e. ing. The indoor unit 4a of the air conditioner 4 and the double floor space 5c are connected via a forward duct 7a. The ceiling space 5b and the indoor unit 4a are connected via a return duct 7b.
The rack row 3 is formed by a plurality of racks 2 of the same module arranged in a horizontal row. A plurality of rack mount servers 2a are stored in the rack 2, and heat generated from each server is exhausted to the back together with air sucked from the front by a cooling fan (not shown) mounted on each server. . As a result, the entire rack is configured to suck in cool air from the front and exhaust from the back.

Each rack 2 is arranged so that the intake surface and the intake surface of the adjacent rows and the exhaust surface and the exhaust surface face each other, so that the cold aisle 6a is provided on the intake surface side and the hot aisle is provided on the exhaust surface side. 6b is formed. In the present embodiment, the cold aisle 6a and the hot aisle 6b are open spaces. However, one of the aisles may be capped to partition the two.
A part of the floor surface of the cold aisle 6a is constituted by a perforated panel 5f, and the cold air sent from the air conditioner 4 is blown out to the cold aisle space via the perforated panel 5f. On one end side of each rack row 3, a distribution board unit (PDU) 9 for supplying power to the rack is disposed.
In each rack row 3, a rack type air conditioner 8 (indoor unit) is arranged as a local air conditioner in the vicinity of a server having a large internal heat generation. The rack-type air conditioner 8 includes an indoor unit 8a, an outdoor unit 8b, and a refrigerant pipe 8c that connects them. The indoor unit 8a includes an evaporator 8e, a blower fan 8d, and a control unit 8f as main components. Each of the outdoor units 8b includes a condenser, a blower fan, and a compressor (not shown) as main components. The indoor unit 8a is the same module as the server rack, and the intake / exhaust direction is opposite to that of the rack 2. In other words, the hot aisle space is arranged so as to suck in high-temperature exhaust air and blow out cooling air to the cold aisle side.

  Referring also to FIG. 3, two wind direction louvers 8g and 8h are provided on the front surface of the blower fan 8d of the indoor unit 8a. The wind direction louver 8g is configured such that the flap 8i can be rotated in the vertical direction by the drive unit 8k and the guide rod 8m. The wind direction louver 8h is configured to be able to turn the flap 8j left and right by the same mechanism.

  The rack air conditioning system 1 is configured as described above, and the cooling of each rack 2 is performed as follows. The room air introduced into the air conditioner 4 exchanges heat in the evaporator 4e to become cold air, and is sent to the double floor space 5c by the blower 4c through the forward duct 7a. The cold air passes through the perforated panel 5f, is supplied to the cold aisle 6a, is further introduced into each server rack, and is cooled to the hot aisle 6b as high-temperature exhaust after cooling the server 2a. A part of the hot exhaust gas rises as it is in the hot aisle 6b, is led to the ceiling space 5b from the ceiling suction port 5h, and is returned to the air conditioner 4 through the return side duct 7b. Further, a part of the high-temperature exhaust is taken into the indoor unit 8a of the rack type air conditioner 8, cooled by the evaporator 8e in the unit to become cold air, blown out to the cold aisle 6a by the blower fan 8d, It is mixed with cold air and sucked into each server rack as described above. Each server rack is cooled by the circulation of indoor air as described above.

  Next, wind direction control and temperature control in the control target area of each rack type air conditioner will be described. Referring to FIG. 2, cold aisle 6a is divided into control target regions R1 to R6 that rack type air conditioners 8a-1 to 8a-6 share. Each air conditioner performs wind direction control so that the temperature distribution in the control target region is uniform. Hereinafter, the rack type air conditioner 8a-1 will be described as an example. Referring to FIG. 3, a temperature sensor Sk (k = 1-4) is disposed in the control target region R1 of the rack type air conditioner 8a-1, and measures the temperature Tk at each position. These measurement values are configured to be taken into a storage unit (not shown) of the control unit 8f. A wind direction pattern table is also stored in the storage unit of the control unit 8f. FIG. 10 is a diagram conceptually showing the contents. Each column Fij stores flap angle data in the vertical and horizontal directions of the louvers 8g and 8h. The control unit 8f is configured to perform a necessary calculation based on the temperature measurement value, select an optimum wind direction pattern from the eight wind direction patterns F11 to F22, and issue a control command to each drive unit.

なお、本実施形態ではｎ＝４である。演算結果に基づき、分散値が最小の風向パターンを選択して運転が継続される（Ｓ１０５）。さらに、選択した風向パターンについて、最高温度Ｔｍａxが設定温度Ｔ０±α以内に収まっているか否かが判定される（Ｓ１０６）。この範囲から外れているときは冷房能力を増減させて、設定温度Ｔ０に近づける制御を行う（Ｓ１０７）。この制御をタイムアップとなるまで行い（Ｓ１０８）、以降、上記ステップを繰り返す。
なお、本実施形態では風向パターンを上下、水平方向それぞれ４パターンとしたが、コールドアイルの広さやラック配置状況に応じて適切なパターンを選択することができる。温度センサの配置数についても同様である。
また、ルーバフラップは全て同一方向のみ回動する形態としたが、フラップ群を複数分割して多方向に回動可能な形態とし、より詳細な風向制御を行う形態としてもよい。
また、上記風向パターン制御を運転開始時や、任意の時に手動で行う形態としてもよい。 Next, referring to FIG. 4, the air flow direction control and the temperature control flow of the rack type air conditioner 8a-1 are performed as follows. With the start of control, the timer count is started with a sufficiently long interval (S101), and the following control is performed at a predetermined interval. First, the operation is sequentially tried for a predetermined time with each wind direction pattern Fij (i = 1−2, j = 1−4) in FIG. 10 (S102). During this time, the temperature is measured by the temperature sensor Sk (S103), and the temperature dispersion value Vij ² expressed by the equation (1) is calculated for each wind direction pattern (S104).

In this embodiment, n = 4. Based on the calculation result, the wind direction pattern with the smallest dispersion value is selected and the operation is continued (S105). Further, it is determined whether or not the maximum temperature Tmax is within the set temperature T0 ± α for the selected wind direction pattern (S106). When the temperature is out of this range, control is performed to increase or decrease the cooling capacity so as to approach the set temperature T0 (S107). This control is performed until time is up (S108), and then the above steps are repeated.
In the present embodiment, the wind direction pattern is four patterns in the vertical and horizontal directions, but an appropriate pattern can be selected according to the size of the cold aisle and the rack arrangement situation. The same applies to the number of temperature sensors.
In addition, the louver flaps are all configured to rotate only in the same direction. However, the flap group may be divided into a plurality of directions so that the flap group can be rotated in multiple directions, and more detailed wind direction control may be performed.
Further, the wind direction pattern control may be manually performed at the start of operation or at an arbitrary time.

(Second embodiment)
Furthermore, another embodiment of the present invention will be described. The rack air-conditioning system 20 according to this embodiment does not control the wind direction for each local air conditioner, but controls the wind direction in cooperation with a plurality of rack-type air conditioners.
FIG. 5 is a diagram showing the control target area division of the rack air conditioning system 20. FIG. 6 is a diagram showing a flow direction / temperature control flow of the control target region R1.
Referring to FIG. 5, the configuration of rack air conditioning system 20 is different from rack air conditioning system 1 described above in that control target regions R21 and R22 are provided in units of cold aisles. Further, temperature sensors S20 to S29 are arranged in the region. Furthermore, a control unit (not shown) for performing the following control is provided. Since other configurations are the same as those of the above-described embodiment, a duplicate description is omitted.

Next, the flow direction / temperature control flow of this embodiment will be described with reference to FIG. 6 by taking the control target region R1 as an example. A timer count is started with the start of control (S201), and the following control is performed at predetermined intervals. First, for each of the air conditioners 8a-1 to 8a-3, trial operation is sequentially performed for a certain period of time by each wind direction pattern Fij (i = 1−2, j = 1−4) of FIG. 10 (S202). During this time, the temperature is measured by the temperature sensors S (m) a to S (m) d (m = 1-4) (S203), and the temperature dispersion value Vij ^{2 in the} equation (1) is calculated for each wind direction pattern. (S204). In this embodiment, n = 16.
Based on the calculation result, the wind direction pattern with the smallest dispersion value is selected and the operation is continued (S205). Further, in the wind direction pattern, it is determined whether or not the maximum temperature Tmax is within the set temperature T0 ± α with respect to the selected wind direction pattern for each air conditioner (S206). When it is out of this range, control is performed to increase or decrease the cooling capacity of the corresponding air conditioner so as to approach the set temperature T0 (S207). The control in S206 and S207 is repeated until the time is up (for example, one week) (S208). After the time is up, the process returns to S201 and the above steps are repeated.

(Third embodiment)
Furthermore, another embodiment of the present invention will be described. FIG. 7 is a diagram showing a configuration of the rack air conditioning system 30 according to the present embodiment. The configuration of the rack air-conditioning system 30 is different from the above-described rack air-conditioning system 20 in that an infrared human sensor 32 is provided on the ceiling of the control target regions R31 and R32. The sensor output is transmitted to the control unit 33, and based on this, the control unit 33 is configured to issue an operation command necessary for the corresponding rack type air conditioner. Since other configurations are the same as those of the above-described embodiment, a duplicate description is omitted.

Next, an air conditioning control flow of the rack air conditioning system 30 will be described with reference to FIG. When the control is started, the human sensor 32 starts operating (S301), and the wind direction and capacity control of the cold aisle are performed in the same manner as in FIG. 6 of the above-described embodiment (S302). During this time, when any human sensor 32 detects the presence of an operator (YES in S303), the set temperature of the adjacent rack type air conditioner is changed from T0 to T0 ′ (T0 ′> T0) (S304). ). Thereafter, when human sensor 32 no longer detects the presence of the worker (YES in S305), the set temperature is lowered again from T0 ′ to T0 after a predetermined time has elapsed (S306), and normal operation is resumed.
In this embodiment, human sensors are installed and controlled at a plurality of locations on the cold aisle, but human sensors are installed near the entrance of the machine room, and set temperature control is performed by detecting entrance / exit. You can also.

(Fourth embodiment)
Furthermore, another embodiment of the present invention will be described. In the present embodiment, the wind direction of the rack type air conditioner is changed in conjunction with the detection of the human sensor. Since the configuration of the present embodiment is the same as that of the above-described embodiment, redundant description is omitted.
Next, the air conditioning control flow of the rack air conditioning system 40 will be described with reference to FIG. When the control is started, the human sensor 32 starts to operate (S401), and the wind direction and capacity control of the cold aisle are performed in the same manner as in FIG. 6 of the above embodiment (S402). During this time, when any human sensor 32 detects the presence of the worker (YES in S403), the wind speed pattern is changed to a predetermined wind speed pattern (for example, upward or downward wind direction, flat wind speed distribution, etc.). (S404). Thereafter, when the human sensor 32 no longer detects the presence of the worker (YES in S405), the original wind speed pattern is restored (S406), and normal wind direction / capacity control is performed.
By such control, it is possible to improve the working environment when the worker enters the room.

  The present invention is widely applicable to an air conditioning system using a rack type air conditioner regardless of the type of heat source, refrigerant, air conditioning system, building structure, and the like.

It is a figure which shows the structure of the rack air conditioning system 1 which concerns on 1st embodiment. It is a figure which shows the control object area | region division of the rack air conditioning system. It is a figure which shows control object area | region R1 of rack type air conditioner 8a-1. It is a figure which shows the wind direction and temperature control flow of the rack air conditioning system. It is a figure which shows the control object area | region division of the rack air conditioning system 20. FIG. It is a figure which shows the wind direction and temperature control flow of control object area | region R1. It is a figure which shows the structure of the rack type air conditioner. It is a figure which shows the air-conditioning control flow of the rack air conditioning system. It is a figure which shows the air-conditioning control flow of the rack air conditioning system. It is a figure which shows notionally the wind direction pattern table of rack type air conditioner 8a-1. 1 is a diagram showing a conventional rack air conditioning system 100. FIG.

Explanation of symbols

1, 20, 30 ... Rack air conditioning system 2 ... Rack 3 ... Rack row 4 ... Ambient air conditioner 5 ... Information communication machine room 5b ... Ceiling space 5c · · Double floor space 5d · · · floor panel 5e · · · ceiling panel 5f · · · perforated panel 6a · · · cold aisle 6b · · · hot aisle 8 · · · · rack type air conditioners 8g, 8h ..Wind direction louver 32 ... Human sensor

Claims (4)

An operation method of a rack air conditioning system that cools a server rack with one or a plurality of air conditioners including a rack type air conditioner in a room where a cold aisle and a hot aisle are formed by one or a plurality of server rack rows,
For the target rack type air conditioner, changing the wind direction pattern and measuring the temperature at a plurality of positions in the control target area of the target rack type air conditioner for each wind direction pattern;
Calculating a temperature dispersion value for each wind direction pattern;
A step of operating the target rack type air conditioner with a wind direction pattern that minimizes the temperature dispersion value; and
A method for operating a rack air-conditioning system comprising: According to claim 1, so that the temperature of the maximum temperature position is the set temperature at variance minimum wind pattern, a step of capacity control of the target rack type air conditioner, the rack conditioning system further comprising how to drive. The target rack type air conditioner is a plurality of grouped rack type air conditioners,
The control target area is a merged area of control target areas of a plurality of rack-type air conditioners; and
Each rack type air conditioner is operated by the wind direction pattern that minimizes the temperature dispersion value in the merged area.
The operation method of the rack air-conditioning system according to claim 1 or 2 . In claim 3 , when one or more of the plurality of grouped rack type air conditioners have failed, the remaining normal rack type air conditioners have a wind direction pattern that minimizes the temperature dispersion value of the merged area. An operation method of a rack air-conditioning system, wherein the remaining normal rack-type air conditioners are operated.

Images