Switch cabinet arrangement with a housing, an electrochemical energy storage device housed therein and an extinguishing system

Description

[0001] The invention is based on a switch cabinet assembly with at least one housing and at least one electrochemical energy storage device accommodated therein, as well as an extinguishing system likewise accommodated in the housing. Such a switch cabinet assembly is described in EP 2 076 317 B1. A similar switch cabinet assembly is also described in DE 10 2006 010 360 B3. A switch cabinet assembly with the features of the preamble of claim 1 is known from CN 112 421 406 A1. A similar switch cabinet assembly is described in CN 207 085 120 U.

[0002] In IT applications, an uninterruptible power supply (UPS) with electrochemical energy storage devices, such as batteries or accumulators, is often used to secure the power supply to servers. These electrochemical energy storage devices must be ventilated according to DIN EN 62485-2. An extinguishing system is also used for fire protection. For a compact design, both systems are often housed in the same enclosure. When the extinguishing system is triggered, an extinguishing gas escapes and floods the enclosure. To ensure a sufficiently high concentration of the extinguishing gas in the enclosure for optimal fire protection, the cabinet must be designed to be as fluid-tight as possible. On the other hand, the enclosure or the control cabinet arrangement must be as well sealed from the environment as possible to achieve the desired IP protection class.

[0003] Accordingly, the ventilation requirement according to DIN EN 6248-2 competes with the enclosure's tightness required to maintain the extinguishing gas concentration and achieve a high IP protection class. To solve this problem, electrically controlled closure flaps in the enclosure's outer walls are known from the state of the art, but these require complex electrical control. Furthermore, these electrically controlled closure flaps have a comparatively high installation depth, which they extend into the enclosure, and are costly.

[0004] It is therefore the object of the invention to provide a switch cabinet arrangement which, on the one hand, provides the ventilation of the interior required for the installation of batteries and, on the other hand, ensures in the event of a fire that the extinguishing gas flooding the housing is maintained at a sufficiently high concentration for optimal fire protection.

[0005] This object is achieved by a switch cabinet arrangement having the features of claim 1. Advantageous embodiments of the invention are the subject of the dependent claims.

[0006] Accordingly, it is provided that at least one gas-permeable membrane is arranged diametrically opposite each other on at least two outer walls of the at least one housing, via which membrane a gas atmosphere inside the at least one housing is in fluid communication with a gas atmosphere in the environment of the at least one housing. The gas permeability of the membrane, for example its porosity, is adjusted such that a gas of an extinguishing agent which has (much) larger molecules than hydrogen cannot pass through the membrane. This in turn means that liquids, in particular water, cannot pass through the membrane. The porosity can be adjusted, for example, via the density and the opening cross-section of a large number of fibrils in the membrane.

[0007] For example, a first membrane can be arranged at a lowest point and a second membrane at a highest point of a housing, for example a control cabinet, an uninterruptible power supply (UPS), or a cooling device (liquid cooling package - LCP). In this way, a diagonal airflow can be created through natural, potential pressure differences. The membrane can be designed to allow air to pass through and otherwise prevent water from penetrating through it, thus ensuring a high IP protection class for the control cabinet assembly. Furthermore, the membrane can be designed to block the organic molecules of a gaseous extinguishing agent, which are comparatively very long-chain compared to air and hydrogen, and thus prevent them from escaping from the control cabinet assembly in the event of a fire. A suitable membrane is described in EP 2 404 652 B1. The membrane can be part of a pressure equalization plug.A suitable pressure equalization plug is sold under the trade name PMF 200542 by WL Gore Associates GmbH.

[0008] Accordingly, the gas-permeable membranes can be permeable to at least hydrogen gas (H2) and impermeable to liquids, especially water. Furthermore, the gas-permeable membranes can have a significantly reduced permeability, at least compared to the permeability to hydrogen gas. This differentiation in permeability is possible in particular because, on the one hand, hydrogen gas has a very small molecular size and, on the other hand, the quenching gases are often long-chain (organic) molecules.

[0009] Thus, in one embodiment of the invention, the membrane can comprise or consist of a microporous expanded polytetrafluoroethylene (ePTFE). The pore size of the membrane can thus be adjusted to provide, on the one hand, good permeability for hydrogen gas and, on the other hand, significantly reduced permeability for the comparatively much larger molecules of the quenching gas. Furthermore, adjusting the pore size in the manner described above ensures that the membrane is also impermeable to liquids, especially water.

[0010] For example, the gas-permeable membrane can have a plurality of fibrils with a diameter that is many times smaller than the diameter of a water droplet with which the control cabinet arrangement and in particular the membrane could be exposed in the application, for example when the control cabinet arrangement is exposed to the weather.

[0011] The at least one membrane can have a gas permeability for air of at least 14 l / min at an overpressure of 10-12 mbar inside the control cabinet arrangement compared to the environment of the control cabinet arrangement.

[0012] The gas-permeable membrane can be permeable to hydrogen gas (H 2 ) and essentially impermeable to an extinguishing gas of the extinguishing system, preferably to long-chain carbon compounds, particularly preferably to the gas perfluoro(2-methyl-3-pentanone) (C 6 F 12 O). The high difference in gas permeability between the hydrogen and the extinguishing gas is particularly achievable because even small differential pressures >0 mbar are sufficient to widen the openings in the membrane sufficiently large for hydrogen molecules. Even with a maximum pressure surge of the extinguishing gas at the moment the extinguishing system is triggered, no significant drop in the concentration of the extinguishing gas could be detected experimentally. The gas permeability can be determined using a manometric method.

[0013] For example, the gas permeability (permeability) for hydrogen gas (H 2 ) can be at least 5 times, preferably at least 10 times greater than for the extinguishing gas, in particular for C 6 F 12 O.

[0014] The gas-permeable membrane can be arranged in a fluidic transition of a pressure equalization valve. The pressure equalization valve can, for example, be designed as the pressure equalization plug described above.

[0015] The fluidic transition can be gas-permeable from the interior of the at least one housing to the environment of the at least one housing and gas-impermeable in the opposite direction.

[0016] The control cabinet arrangement can comprise multiple housings that form a control cabinet row of fluidically interconnected housings. The housings can be a control cabinet housing and / or a cooling device housing and / or an uninterruptible power supply and / or another housing commonly used in control cabinet construction that can be integrated into a control cabinet row. The two microporous membranes can be arranged in the outer wall of different housings in the control cabinet row.

[0017] The extinguishing agent can be or contain perfluoro(2-methyl-3-pentanone). As a long-chain molecule, it is either retained by the membrane or allowed to pass through only with a significant delay, so that in the event of a fire, a minimum concentration of the extinguishing agent gas is maintained in the housing for the duration required for extinguishing purposes.

[0018] The extinguishing system can have an extinguishing agent dosing device which is designed to dose a quantity of extinguishing agent, preferably perfluoro(2-methyl-3-pentanone), into the interior of the switch cabinet arrangement in the event of extinguishing, which generates an atmospheric overpressure in the interior of the at least one housing compared to the environment of the switch cabinet arrangement of at least 25 mbar, preferably at least 35 mbar and particularly preferably at least 40 mbar.

[0019] The membrane may be configured to maintain the overpressure, preferably at least 80%, for at least 3 minutes, preferably for at least 5 minutes and particularly preferably for at least 12 minutes.

[0020] A concentration of the extinguishing agent in the atmosphere in the housing can be at least 5%, preferably at least 6% and particularly preferably at least 8% in the event of extinguishing, wherein the membrane is designed to maintain the concentration, preferably at least 80%, for at least 3 minutes, preferably for at least 5 minutes and particularly preferably for at least 12 minutes.

[0021] A baffle plate can be arranged inside the housing, upstream of an extinguishing agent outlet of the extinguishing system. The baffle plate can be designed to improve the distribution of the extinguishing gas inside the control cabinet assembly.

[0022] Further details of the invention are explained with reference to the following figures. Figure 1 shows a first embodiment of a switch cabinet arrangement according to the invention; and Figure 2 shows a second embodiment of a switch cabinet arrangement according to the invention.

[0023] The Figure 1shows a first exemplary embodiment of a switch cabinet arrangement according to the invention, which consists of a single housing 1, for example a switch cabinet housing. In addition to the components of an electrical switchgear or server installations of an IT environment (not shown), an uninterruptible power supply (UPS) 2 and an extinguishing system 3 are also arranged in the switch cabinet housing. An exemplary extinguishing system is described in detail in EP 2 076 317 B1. The extinguishing system 3 is designed to flood the switch cabinet housing with an extinguishing gas following a detected fire development inside the switch cabinet. In order to exert a sufficient extinguishing effect, it must be ensured that the extinguishing gas is maintained at a sufficient concentration inside the switch cabinet housing for a sufficient period of time.For this purpose, it is essential that the interior of the control cabinet housing is designed to be substantially fluidically sealed to the environment of the control cabinet housing 1.

[0024] The gas tightness required for firefighting conflicts with the legally required ventilation of enclosures containing batteries, such as a UPS 2. This ventilation requirement also competes with the requirement for electrical switchgear and IT environments to achieve the highest possible IP protection class.

[0025] To solve this problem, the embodiment according to Figure 1It is proposed that a membrane 5 is arranged diametrically opposite each other on opposite side walls 4 of the switch cabinet housing 1, which membrane is permeable to outgassing from the UPS in the event of a failure, but sufficiently impermeable to an extinguishing gas from the extinguishing system 3. If the membrane 5 is impermeable to an extinguishing gas from the extinguishing system 3, it is also impermeable to liquids, in particular water, in order to achieve the desired IP protection class.

[0026] The membranes 5 are spaced apart within the control cabinet housing to ensure the highest possible pressure difference for natural ventilation of the control cabinet housing. Accordingly, a first membrane is arranged in a lower region of the side wall at the front of the housing 1, while a second membrane 5 is arranged on the opposite side wall 4, at an upper end thereof, and at a rear of the housing 1. The membranes 5 can be designed, for example, as a pressure equalization filter, as described, for example, in EP 2 404 652 B1.

[0027] The Figure 2shows a switch cabinet arrangement forming a row of switch cabinets, consisting of two central housings 1, each of which has a UPS 2 and an extinguishing system 3, and adjacent to the outside of each housing 1 with a cooling device (Liquid Cooling Package - LCP). In this embodiment, the membranes 5 are distributed among the various housings 1, whereby each housing 1 clearly has only one membrane 5. Two first membranes 5 for the air inlet are arranged in the base of the UPS 2, while two second membranes 5 are arranged in the roof element of the LCP housing 1. Due to natural temperature fluctuations, this arrangement of the membranes can achieve natural ventilation of the switch cabinet arrangement, analogous to the individual housing arrangement according to Figure 1 .

[0028] The described solutions have the advantage of being particularly space-saving and cost-effective to retrofit. The membranes allow for continuous air exchange between the interior of the control cabinet and the surrounding area. Since hydrogen (H2) is the smallest molecule, it is directly removed when the batteries of the UPSs 2 outgas, resulting in a pressure increase inside the control cabinet, preventing an explosive mixture from forming inside the control cabinet.

[0029] The membranes 5 also ensure that in the event of a fire, after the extinguishing system 3 has been triggered, a sufficiently long holding time of the extinguishing agent is ensured inside the control cabinet arrangement.

[0030] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential for the realization of the invention both individually and in any combination. List of reference symbols

[0031] 1Housing 2Energy storage 3Extinguishing system 4Outer wall 5Membrane

Claims

1. Switchgear cabinet assembly comprising at least one housing (1) and at least one electrochemical energy store (2) accommodated therein and having an extinguishing system (3), wherein at least two outer walls (4) of the at least one housing (1) have arranged diametrically opposite them in each case at least one gas-permeable membrane (5), via which a gas atmosphere in the interior of the at least one housing (1) is fluidically connected to a gas atmosphere in the surroundings of the at least one housing (1), wherein a gas permeability of the membrane is set such that a gas of an extinguishing agent of the extinguishing system (3), which has larger molecules in comparison with hydrogen, cannot pass through the membrane.

2. Switchgear cabinet assembly according to claim 1, in which the gas-permeable membranes (5) are permeable to at least hydrogen gas (H2) and impermeable to liquid, in particular water.

3. Switchgear cabinet assembly according to claim 1 or 2, in which the membrane (5) has or consists of a microporous expanded polytetrafluoroethylene (ePTFE).

4. Switchgear cabinet assembly according to one of the preceding claims, in which the gas-permeable membrane (5) has a multiplicity of fibrils with a diameter which is many times smaller than the diameter of a water drop.

5. Switchgear cabinet assembly according to one of the preceding claims, in which the at least one membrane (5) in each case at an overpressure of 10-12 mbar in the interior of the switchgear cabinet assembly has a gas permeability to air of at least 14 I / min with respect to the surroundings of the switchgear cabinet assembly.

6. Switchgear cabinet assembly according to one of the preceding claims, in which the gas-permeable membrane (5) is permeable to hydrogen gas (H2) and substantially impermeable to an extinguishing gas of the extinguishing system (3), preferably to long-chain carbon compounds, particularly preferably to the gas of perfluoro(2-methyl-3-pentanone) (C6F12O).

7. Switchgear cabinet assembly according to claim 1, in which the gas permeability to hydrogen is at least 5 times, preferably at least 10 times greater than for the extinguishing gas.

8. Switchgear cabinet assembly according to one of the preceding claims, in which the gas-permeable membrane (5) is arranged in a fluidic transition of a pressure compensation valve.

9. Switchgear cabinet assembly according to claim 7, in which the fluidic transition from the interior of the at least one housing (1) to the surroundings of the at least one housing (1) is gas-permeable and gas-impermeable in the opposite direction.

10. Switchgear cabinet assembly according to one of the preceding claims, in which a plurality of housings (1) form a switchgear cabinet row with housings (1) fluidically connected to one another, wherein the two microporous membranes (5) are arranged in the outer wall (4) of different housings (1) of the switchgear cabinet row.

11. Switchgear cabinet assembly according to one of the preceding claims, in which the extinguishing agent is or has perfluoro(2-methyl-3-pentanone).

12. Switchgear cabinet assembly according to one of the preceding claims, in which the extinguishing system (3) has an extinguishing agent metering unit which is set up, in the event of extinguishing, to meter an amount of extinguishing agent, preferably perfluoro(2-methyl-3-pentanone), into the interior of the switchgear cabinet assembly, which extinguishing agent metering unit in the interior of the at least one housing (1) generates an atmospheric overpressure with respect to the surroundings of the switchgear cabinet assembly of at least 25 mbar, preferably of at least 35 mbar and particularly preferably of at least 40 mbar.

13. Switchgear cabinet assembly according to claim 12, in which the membrane (5) is set up to keep the overpressure for at least 3 minutes, preferably for at least 5 minutes and particularly preferably for at least 12 minutes.

14. Switchgear cabinet assembly according to one of the preceding claims, in which a concentration of the extinguishing agent in the event of extinguishing is at least 5%, preferably at least 6% and particularly preferably at least 8%, wherein the membrane (5) is set up to keep the concentration preferably for at least 3 minutes, preferably for at least 5 minutes and particularly preferably for at least 12 minutes.

15. Switchgear cabinet assembly according to one of the preceding claims, in which a baffle plate is arranged in the interior of the housing (1) upstream of an extinguishing agent outlet of the extinguishing system (3).