JP4905992B2 - Rack type air conditioner and operation method thereof - Google Patents

Description

  The present invention relates to a rack type air conditioner and an operating method thereof, and more particularly to a rack type air conditioner suitable for an air conditioning system of an information communication machine room that uses both ambient air conditioning and local air conditioning.

In recent years, with the advancement of IT in society, the speed, capacity, and density of information communication devices are rapidly increasing. 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・ There is a problem of high-temperature failure of the equipment. 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. 9 shows a rack air-conditioning system 100 according to this system. 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. FIG. 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.
JP 2003-166729 A

However, in an air conditioning system with a conventional local air conditioner, the temperature of the cold aisle rises when the local air conditioner drops in capacity (failure, shutdown, start-up until the refrigeration cycle stabilizes, or when the thermo is off), and information communication There is a risk of high temperature failure of the equipment. In particular, when the local air conditioner in the high heat generation region is in a reduced capacity state, the risk is high. In order to avoid such obstacles, it is necessary to provide redundancy in the installation of local air conditioners, such as the arrangement of spare units, but this will increase the initial cost and increase the amount of air conditioning space. -There is a problem that the mounting rate of the apparatus is reduced.
The present invention is intended to solve such problems, and does not cause an increase in initial cost or a reduction in the mounting rate, and causes a high-temperature failure of information communication equipment / devices when the capacity of a local air conditioner is reduced. A rack type air conditioner that can be avoided is provided.

The gist of the present invention is as follows. That is, the rack-type air conditioner according to the present invention is
(1) A rack used in a rack air-conditioning system that uses double air-blowing air-conditioning with an ambient air conditioner and local air-conditioning with a rack-type air conditioner in a room where cold aisles and hot aisles are formed by a server rack row Type air conditioner that introduces hot aisle-side high-temperature exhaust into the machine, an air introduction part that introduces cooling air from the double floor space into the machine, and air that blows cooling air to the cold aisle side It is characterized by comprising a fan and flow path switching means capable of switching the supply source of the blown air to either the exhaust from the exhaust introduction part or the cold air from the cold air introduction part.
(2) The above invention is characterized in that at least the fan drive power supply can be supplied via an uninterruptible power supply circuit.
With such a configuration, it is possible to use the cold heat capacity under the double floor in an emergency evacuation when the commercial power supply is cut off, such as a power failure, and it is possible to suppress a rapid temperature rise of the cold aisle for a certain period of time.

Moreover, the operation method of the rack type air conditioner used in the rack air conditioning system according to the present invention is as follows:
(3) When the capacity is reduced, the blower fan is continuously operated, and the flow path switching unit is switched from the exhaust introduction part side to the cold air introduction part side.
(4) In the above (3), the capacity reduction is caused by device activation, failure, or thermo-off.
(5) In the above (2), power is supplied from the uninterruptible power supply circuit when the commercial power is cut off, the blower fan is continuously operated, and the supply source of the blown air is switched from the exhaust introduction part side to the cold air introduction part side. It is characterized by.
(6) In the operation method of the rack air-conditioning system, the rack-type air conditioner continuously operates the blower fan when the capacity is reduced, and the flow path switching unit is changed from the exhaust introduction part side to the cold air introduction part side. When operating by switching, the air volume of the ambient air conditioner is increased.
With the change in the cold air supply method of the rack type air conditioner, the environment of the cold aisle space may deteriorate. The present invention avoids such adverse effects by increasing the amount of cold air supplied by increasing the air volume of the ambient air conditioner.

According to each said invention, even when the capability of a local air conditioner falls, the cold air and cold storage heat under a double floor can be utilized, and the high temperature failure of an information communication apparatus can be prevented.
Further, since the local air conditioner can be arranged without providing redundancy, the initial cost can be reduced.

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 order to avoid redundant description, the same components are denoted by the same reference numerals in the respective drawings. 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 an air conditioning system 1 using a rack type air conditioner 20. FIG. 2 is a diagram illustrating a cross-sectional configuration of the indoor unit 20a of the rack-type air conditioner 20 according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a planar configuration of the air conditioning system 1. FIG. 4 is a diagram illustrating a cold air flow path when the air conditioning system 1 is activated. FIG. 5 is a diagram illustrating an operation control flow when the air conditioning system 1 is activated.

Referring to FIGS. 1 and 3, an air conditioning system 1 is housed in an information and communication machine room 5, and a server rack 2 constituting a rack row 3 is divided into an air conditioner 4 that is an ambient air conditioner and a rack that is a local air conditioner. This is a system that is cooled by the mold air conditioner 20.
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 server racks 2 of the same module arranged in a horizontal row. The server rack 2 stores a plurality of rack mount servers 2a, 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 server rack 2 is arranged so that the intake surface and the intake surface of the adjacent rows face each other, 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 hot air is provided on the exhaust surface side. An aisle 6b is formed.
In each rack row 3, a rack type air conditioner 20 is arranged as a local air conditioner in the vicinity of a server having a large internal heat generation. The air conditioner 20 is the same module as the server rack, and the intake / exhaust direction is opposite to that of the server 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.
A part of the floor surface of the cold aisle 6a is constituted by a perforated panel 5f. A cold air outlet 5g is provided on the lower floor surface of the rack-type air conditioner 20. Thus, the cool air sent from the air conditioner 4 can be supplied to the cold aisle space and the rack type air conditioner 20 as will be described later.
On one end side of each rack row 3, a switchboard unit (PDU) 9 for supplying power to the in-row rack is disposed. The PDU 9 is also configured in the same module as the server rack 2.

Referring also to FIG. 2, the rack-type air conditioner 20 includes an indoor unit 20a, an outdoor unit 20b, and a refrigerant pipe 20c that connects them. The indoor unit 20 a includes an evaporator 23, a blower fan 24, and a control unit 27 as main components inside the housing 22. The indoor unit 20a is placed on the gantry 10 placed on the floor panel 5d. A fan guard 28 is attached to the front surface of the fan 24.
An exhaust air inlet 25 is provided on the back side of the housing 22 so that hot-air exhaust can be introduced. Moreover, the cool air inlet 26 is provided in the bottom face side of the housing | casing 22, and it is comprised so that the cool air supplied from the air conditioner 4 can be introduce | transduced via the cool air blower outlet 5g. Shutters 25a and 26a are attached to the exhaust air inlet 25 and the cold air inlet 26, respectively, and can be opened and closed by operation of gear motors and link mechanisms (both not shown) provided in the drive units 25b and 26b, respectively. Has been. The rack type air conditioner 20 is configured to be able to switch the flow path of the intake air to the exhaust intake side or the cold air intake side by such a mechanism.

  The rack air-conditioning system 1 is configured as described above. Next, the cooling of each server rack 2 during steady operation will be described with reference to the cold air and exhaust flow paths of FIG. In this case, the exhaust air inlet 25 of the air conditioner 20 is open and the cold air inlet 26 is closed. The indoor air introduced into the air conditioner 4 exchanges heat in the evaporator 4e to become cold air, and is sent out by the blower 4c to the double floor space 5c through the forward duct 7a. The cold air is supplied to the cold aisle 6a through the perforated panel 5f. Furthermore, after being introduced into each server rack and cooling the server 2a, it is discharged into the hot aisle 6b as high temperature exhaust. 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. A part of the high-temperature exhaust gas is taken into the rack type air conditioner 20 through the exhaust air inlet 25, cooled by the evaporator 23 in the apparatus to become cold air, and blown out to the cold aisle 6 a by the blower fan 24. Here, it is mixed with the cold air from the air conditioner 4 and sucked into each server rack as described above. Each server rack is cooled by the circulation of indoor air as described above.

  Next, with reference to FIGS. 4 and 5, the operation control flow and the cool air flow path until the refrigeration cycle is stabilized when the rack type air conditioner 20 is started will be described. The following control is performed by a command from the control unit 27 of each rack type air conditioner. At the time of starting the rack type air conditioner 20 (S101), the rack type air conditioner 20 is in a temperature rise suppression control operation (S102). That is, the blower fan 24 is continuously operated, the exhaust suction port 25 is closed, and the cold air suction port 26 is opened (S103). As a result, high-temperature exhaust from the hot aisle side is not sucked into the air conditioner 20, and cold air is directly introduced from the cold air inlet 26. As a result, only the cold air from the double floor space 5c is supplied to the cold aisle 6a, and the inflow of hot air from the hot aisle side is not affected by the lack of cooling capacity when the air conditioner 20 is started. A sudden temperature rise of the cold aisle 6a due to is avoided.

Thereafter, the state is maintained until a predetermined time elapses (NO in S104). Here, the predetermined time is set based on the time required from the start of the air conditioner 20 to the rated cooling output. After a predetermined time has elapsed (YES in S104), the routine proceeds to normal control operation (S105). That is, the blower fan is capacity controlled, the exhaust suction port 25 is opened, and the cold air suction port 26 is closed (S106). As a result, the operation is performed by the intake of the hot exhaust gas of the hot aisle 6b from the exhaust suction port 25.

(Second embodiment)
Furthermore, another embodiment of the present invention will be described. The present embodiment relates to a cold air supply control for suppressing a cold aisle temperature rise when there is a decrease in capacity due to a failure or the like of a rack air conditioner during steady operation. Since the configuration of this embodiment is the same as that of the above-described embodiment, illustration and duplication description are omitted.
FIG. 6 is a diagram showing a control flow of the present embodiment. During the steady operation, the rack type air conditioner 20 is operated by normal operation control, that is, capacity control based on the blown air temperature (S201). In this case, intake is performed from the exhaust air inlet 25, and the cold air inlet 26 is closed (S202).

During operation, it is determined whether or not the refrigerant circulation is stopped (S203). The refrigerant circulation stops when an abnormality occurs in the refrigeration cycle system or when the thermostat is turned off. If this is the case, the operation is switched to the temperature rise suppression operation control (S204). That is, continuous operation of the blower fan 24 and intake air are performed from the cold air inlet 26, and the exhaust air inlet 25 is closed (S205). Thereby, since the hot air of the hot aisle 6b is not sucked and cold air is introduced from the cold air inlet 26, a rapid temperature rise of the cold aisle can be avoided.
Thereafter, when the abnormality such as the thermo-on or the refrigerant circuit system is resolved (YES in S206), the process returns to the normal operation control (S201). Note that the thermo-on condition is determined based on the temperature on the suction side.

(Third embodiment)
Furthermore, another embodiment of the present invention will be described. This embodiment is a system that supplies cold air supply power for a local air conditioner from an uninterruptible power supply (UPS) when commercial power is cut off, such as a power failure.
FIG. 7 is a diagram illustrating a power supply system of the rack air conditioning system 30. FIG. 8 is a diagram showing a power supply system when the commercial power supply is shut off.

  Referring to FIG. 7, the configuration of the rack air conditioning system 30 is different from the rack air conditioning system 1 described above in that it includes an uninterruptible power supply (UPS) 31 that mainly includes a battery 31 a, a rectifier 31 b, and an inverter 31 c. That is. Furthermore, the power of the ambient air conditioner 4 and the rack type air conditioner 32 excluding the following emergency supply system is directly supplied from a commercial power supply via the power lines E1, E1a, E1b, E1c. On the other hand, the power supply of the blower fan, the shutter drive unit, and the control unit (all of which are not shown) of the rack type air conditioner 32 that is an emergency supply system is the power line E2, UPS 31, and power lines E3, E3a branched from the power line E1. Supplied via The PDU 9 is also supplied with power via the UPS 31 and the power line E3b. Since other configurations are the same as those of the above-described embodiment, a duplicate description is omitted.

  As shown in the bold line in FIG. 1, all devices and devices receive power from a commercial power source. In this case, the rack type air conditioner 32 is in a state in which the cold air inlet (not shown) is closed and the exhaust inlet (not shown) is opened. A blower fan (not shown) is in capacity control operation.

Next, referring to FIG. 8, when commercial power is cut off, such as a power failure, power supply via power lines E1 and E2 is cut off. For this reason, the refrigerant circuit system of the ambient air conditioner 4 and the rack type air conditioner 32 is in an operation stop state. However, the emergency supply system of the rack type air conditioner 32 is switched to the UPS 31 side, and power is supplied through the battery 31a and the power lines E4, E3, E3a. The same applies to PDU9. In this case, in the rack type air conditioner 32, the cold air inlet is switched to open and the exhaust air inlet is closed, and the blower fan is continuously operated. As a result, even if the commercial power supply is cut off, the cold heat capacity under the double floor can be used for emergency evacuation, and the rapid temperature rise of the cold aisle can be suppressed for a certain period of time.
In this embodiment, the control unit and the shutter drive unit that is the flow path switching unit are configured to supply power from the uninterruptible power supply circuit. However, the configuration is such that power is not used but the mechanical unit such as a weight is operated. It can also be.
Further, in this embodiment, the ambient air conditioners are all supplied with only commercial power, but the blower system may be configured to be able to supply power from an uninterruptible power supply circuit.

  The present invention can be widely applied to a 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 cross-sectional structure of the air conditioning system 1 using the rack type air conditioner. It is a figure which shows the cross-sectional structure of the indoor unit 20a of the rack type air conditioner 20. FIG. 1 is a diagram illustrating a planar configuration of an air conditioning system 1. FIG. It is a figure which shows the flow path of the cold air at the time of starting of the air conditioning system. It is a figure which shows the operation control flow at the time of starting of the air conditioning system. It is a figure which shows the operation control flow in 2nd embodiment. 2 is a diagram showing a power supply system of a rack air conditioning system 30. FIG. It is a figure which shows the electric power supply system at the time of the commercial power supply interruption | blocking of the rack air conditioning system. 1 is a diagram showing a conventional rack air conditioning system 100. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 30 ... Rack air conditioning system 2 ... Server 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 5g-Cold air outlet 6a-Cold aisle 6b-Hot aisle 9-PDU
20, 32 ... Rack type air conditioner 24 ... Blower fan 25 ... Exhaust air inlet 25a ... Shutter 26 ... Cold air inlet 31 ... UPS
E1-E4, E3a, E3b ... Power line

Claims (6)

Rack type air conditioner used in a rack air conditioning system that uses double floor blowout air conditioning with ambient air conditioner and local air conditioning with rack type air conditioner in a room where cold aisle and hot aisle are formed by server rack row Because
An exhaust introduction section for introducing hot aisle high temperature exhaust into the aircraft;
A cold air introduction section for introducing cooling air from the double floor space into the aircraft;
A blower fan that blows out cooling air to the cold aisle side;
A flow path switching means capable of switching the supply source of the blown air to either the exhaust from the exhaust introduction unit or the cold from the cold introduction unit;
A rack-type air conditioner comprising: The rack type air conditioner according to claim 1, wherein at least the fan drive power supply is configured to be supplied via an uninterruptible power supply circuit. The operation method of the rack type air conditioner used in the rack air conditioning system according to claim 1 or 2, wherein the blower fan is continuously operated when the capacity is lowered, and the flow path switching means is cooled from the exhaust introduction part side. A method of operating a rack type air conditioner characterized by switching to the introduction side. The operation method of the rack type air conditioner according to claim 3, wherein the capacity reduction is caused by start-up of equipment, failure or thermo-off. The rack-type air conditioner according to claim 2,
While supplying power from the uninterruptible power supply circuit when commercial power is cut off,
The blower fan is operated continuously, and
Switch the supply source of the blown air from the exhaust inlet side to the cold air inlet side,
A method of operating a rack type air conditioner characterized by the above. In the rack air conditioning system according to claim 1 or 2,
When the rack type air conditioner continuously operates the blower fan when the capacity is reduced and switches the flow path switching unit from the exhaust introduction side to the cold air introduction side, the ambient air conditioner An operation method of a rack air conditioning system, characterized by increasing an air volume.

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