Coordinated control of multiple components for closed-loop enclosure cooling

One example implementation provides a method for controlling enclosure interior temperature, including obtaining, from a thermostat, temperature data indicative of interior enclosure temperature; determining, using a controller, that the temperature data indicates that the interior enclosure temperature exceeds a set point; simulating for a heat exchanger, using the controller, loss of alternating current (AC) power supply; and thereafter operating, using the controller, the heat exchanger and an air conditioner above the set point.

BACKGROUND

Industry and manufacturing have emerged with the widespread use of enclosures for a variety of content, for example electronics or other items that require protection from the elements as well as cooling. For example, to protect these items from harsh environments, items are typically placed in sealed enclosures or cabinets that permit efficient operation without the threat of being exposed to exterior contaminates including dust, residue, rain and liquids that have the potential to cause serious damage. Since the items (such as electronics or like equipment) often generate heat within the enclosure, various cooling equipment such as air conditioners, heat exchangers, in-line compressed air coolers and filtered fan systems are used to maintain required operating temperatures within the enclosure.

Certain cooling systems often treat the enclosed air only, while sealing out the potential contaminated ambient environment (“closed-loop” cooling). In cases where the ambient air is near room temperature (70-85 degrees Fahrenheit) and when there is not a threat of rain or splashing liquids present outside the enclosure, a filtered fan system is used to maintain a constant flow of filtered ambient air through the enclosure. These filtered fan systems typically are less costly than closed-looped systems and simply employ a fan which induces the cooler ambient air through a filter media into the enclosure, therefore creating a positive pressure inside the enclosure forcing the hot enclosure air out through an exhaust vent.

In circumstances where closed-loop cooling is required, use of a filtered-fan or similar system is unacceptable, as the system is required to keep ambient air (outside the cabinet) on the exterior, only operating on the enclosure air.

SUMMARY

In summary, an embodiment provides a method, comprising: obtaining, from a thermostat, temperature data indicative of interior enclosure temperature; determining, using a controller, that the temperature data indicates that the interior enclosure temperature exceeds a set point; simulating for a heat exchanger, using the controller, loss of alternating current (AC) power supply; and thereafter operating, using the controller, the heat exchanger and an air conditioner above the set point.

Another embodiment provides a system, comprising: a heat exchanger; an air conditioner; and a controller operatively coupled to the heat exchanger and the air conditioner, the controller being configured to: obtain, from a thermostat, temperature data indicative of interior enclosure temperature; determine that the temperature data indicates that the interior enclosure temperature exceeds a set point; simulate for a heat exchanger loss of alternating current (AC) power supply; and thereafter operate the heat exchanger and an air conditioner above the set point.

A further embodiment provides a controller configured to: obtain, from a thermostat, temperature data indicative of interior enclosure temperature; determine that the temperature data indicates that the interior enclosure temperature exceeds a set point; simulate for a heat exchanger loss of alternating current (AC) power supply; and thereafter operate the heat exchanger and an air conditioner above the set point.

DETAILED DESCRIPTION

Reference throughout this specification to “embodiment(s)” (or the like) means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “according to embodiments” or “in an embodiment” (or the like) in various places throughout this specification are not necessarily all referring to the same embodiment.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of example embodiments. One skilled in the relevant art will recognize, however, that aspects can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obfuscation.

As used herein, “connecting” includes indirect connections.

One embodiment provides a cooling system for an enclosure or cabinet that houses components, e.g., heat generating components such as electronics. In an embodiment, the cooling system comprises an air conditioner, a heat exchanger, and a controller configured to coordinate operation of the air conditioner and the heat exchanger to maintain enclosure air within an operating temperature range.

Referring toFIG.1-2, in an embodiment, a controller receives temperature data101that indicates the interior enclosure temperature of an enclosure200. Controller210determines102if the interior enclosure temperature is above a set point. It will be readily understood by those having ordinary skill in the art that the “interior enclosure temperature” may be inferred, e.g., by use of an ambient temperature proxy or via direct measurement of the interior enclosure temperature. Controller210includes or uses a plurality of relays210a,210bto operate contacts or circuits operatively connected to an air conditioner240, a heat exchanger230, a source of alternating current (AC) power250, a source of direct current (DC) power240(such as a battery), or a combination of the foregoing.

In an embodiment, controller210acts to monitor a sensed temperature at101-102, such as ambient air temperature, enclosure air temperature, or a combination thereof, sensed via thermostat220, and in response to a temperature measurement, controller210may act to operate air conditioner240, heat exchanger230, or a combination thereof, e.g., based on comparison to a set point.

In an embodiment, with heat exchanger230operating, controller210is configured to respond to a sensed temperature increase at102by ceasing operation of heat exchanger230in favor of operating air conditioner240when AC power is available, for example as indicated at101-105ofFIG.1. If AC power is not available, controller210may continue operating heat exchanger230and throw an alarm.

By way of example, controller210responds to an ambient air temperature below a threshold, for example 63 degrees Fahrenheit (F), with activation of heat exchanger230(not illustrated inFIG.1), to remove heat from the air of enclosure200and expel the heat into the ambient environment while maintaining a closed loop. In an embodiment, the activation of heat exchanger230is coordinated with the operation of air conditioner240, e.g., air conditioner240is switched off or remains off in favor of using heat exchanger230below a first set point.

In an embodiment, controller210is configured to respond to a temperature at or above a threshold, which may be the same or different than other threshold(s), to activate air conditioner240and cease operation of heat exchanger230, as indicated at105and106ofFIG.1. For example, controller210may be configured to respond to data indicative of a sensed ambient air temperature of above 70 F by activating air conditioner240at106for enclosure cooling and ceasing operation of heat exchanger230at105.

In an embodiment, controller210acts to monitor a sensed power source availability, as indicated at103and108ofFIG.1, such as availability of alternating current power, direct current power, or a combination thereof. In response to a power source's availability, controller240may act to operate air conditioner240, heat exchanger230, or a combination thereof. Further, controller210may issue an alert, alarm, or message in connection with responding to temperature data, power availability data, and/or operational state data for components such as heat exchanger230and air conditioner240.

In an embodiment, controller210is configured to respond to a lack of alternating current power, as indicated at103and108, by activating a direct current power source260, e.g., a battery. In an embodiment, the direct current power source260is operable to operate heat exchanger230but not air conditioner240. Direct power source260may also power controller200, which may be used to issue alerts, alarms, or messages, e.g., to a remote or networked device such as a computer or handset/mobile application.

In an embodiment, controller210is configured to simulate loss of a power source, e.g., alternating current power source250. In one example, controller210is configured to respond to data, such as an indication of ambient air temperature exceeding a high set point, as determined at107, to simulate loss of alternating current power source250, as indicated at110ofFIG.1, activating heat exchanger230, a direct current power source260, or both, as indicated at111. In an embodiment, this may act as a guard against an upper temperate limit violation, allowing heat exchanger230that runs only on direct current to be activated, even when alternating current is available, as determined at108, and is used to simultaneously operate air conditioner240of the enclosure200, as indicated at109and111ofFIG.1.

In the specific example ofFIG.1, it is illustrated that the by use of two set point temperatures, controller210receives temperature data indicative of the enclosure interior temperature, which may be used to initially operate heat exchanger230but not air conditioner240, thereafter stop or cease operation of heat exchanger230in favor of air conditioner, as well as respond to a further increase in temperature by powering both of heat exchanger230and air conditioner240, even if heat exchanger230is normally configured to cease operation while air conditioner240is active (via sensed AC power supply). Controller accomplishes this latter operational state via simulation of AC power loss, as indicated at110ofFIG.1.

It may be desirable to operate enclosure200such as a 5G telecommunications cabinet, housing heat generating electronics, with a closed loop cooling system to protect the contents of the cabinet or enclosure200(e.g., heat generating components201) from ambient air contaminates or other environmental factors such as rain. In one example, a cabinet200may be supplied with battery backup power as DC power source260, for example to run certain electronics on the condition of a loss of alternating current power from a commercial power supply. In such a cabinet200, it may be beneficial to run all or some of the cooling components, such as heat exchanger(s)230or air conditioning unit(s)240, using the direct current supplied by a series of batteries, e.g., 48V DC current supply. However, to run all cooling components on the DC power may be prohibitive. Thus, certain components, such as heat exchanger(s)230, may be supplied with DC power, whereas others, e.g., air conditioner(s)240are configured to run only on and when alternating current power supply250is available.

Further, it may be desirable to reduce the cost or energy consumption of the cooling system for a cabinet or enclosure200. For example, when ambient temperatures permit, it may be beneficial to run certain components, e.g., heat exchanger(s)230, rather than other components, e.g., air conditioner(s)240, because the certain components use less energy. However, the coordination of the various components is required, e.g., because the cabinet200internal temperature must be adequately maintained.

In an embodiment, controller200includes or uses a plurality of relays210a,210b, such as normally closed (NC) and/or normally open (NO) to operate contacts, relays, or circuits operatively connected to air conditioner240, heat exchanger230, a source of alternating current power250, a source of direct current power260(such as a battery), or a combination of the foregoing.

In an embodiment, controller210is configured to respond to a sensed temperature by activating operation of heat exchanger230. In one example, controller210responds to an ambient air temperature below a threshold, for example 63 degrees Fahrenheit (F), to activate heat exchanger230to remove heat from the air of enclosure200and expel the heat into the ambient environment while maintaining a closed loop. In an example, heat exchanger230is configured to run on direct current supplied normally by an alternating current source250, e.g., by transformer (not illustrated inFIG.2) that converts the alternating current into direct current. In one example, heat exchanger230may also run on direct current supplied by a direct current power supply260such as a battery, e.g., when the alternating current is unavailable or is indicated as unavailable (e.g., as further described herein).

In an embodiment, the activation of heat exchanger230is coordinated with the operation of air conditioner240, e.g., air conditioner240is switched off in favor of using heat exchanger230, such as at lower ambient (external to enclosure) temperatures, as sensed by controller210. In one example, an ambient air temperature setpoint of 63 F is used as an indication that air conditioner240should cease running and heat exchanger230should begin or continue running.

In an embodiment, controller210is configured to respond to a temperature at or below a threshold, which may be the same or different than other threshold(s), to activate air conditioner240and cease operation of heat exchanger230. For example, the controller may be configured to respond to data indicative of a sensed ambient air temperature of above 70 F by activating air conditioner240for enclosure cooling and ceasing operation of heat exchanger230. Further, controller may use a set point above 70 F to ensure a thermal limit is not exceed for enclosure air temperature, e.g., operating both heat exchanger230and air conditioner240at the same time.

In an embodiment, controller210is configured to simulate loss of a power source, e.g., alternating current from AC power supply250. In one example, controller210is configured to respond to data, such as an indication of ambient air temperature, to simulate loss of alternating current power, e.g., removing a signal from a relay210athat typically acts to indicate that air conditioner240is active and that heat exchanger230should remain inactive, activating heat exchanger230in combination with air conditioner240. In an embodiment, heat exchanger230may thereafter run using a direct current power source260, the alternating power source250, or both. In an embodiment, this may act as a guard against an upper temperate limit violation, e.g., of the enclosure air temperature and/or the ambient air temperature, allowing heat exchanger230that runs typically on direct current to be activated, even when alternating current is available and is used to simultaneously operate air conditioner240of enclosure200.

In an embodiment, a housing, e.g., controller housing, houses a controller200with a touchscreen for data entry. Controller200is configured to control relays210a,210b, contacts or switches for air conditioner240and heat exchanger230, as described herein. In the example ofFIG.2, controller200is operatively connected to a lower panel of terminal blocks (not explicitly illustrated) that receive alternating current and direct current power as well as act for connecting heat exchanger230and air conditioner240, or several of these, to controller housing and thus operatively connecting them to controller200. Controller200and the terminal blocks are connected via relays210a,210b, which may include or alternatively be implemented as switches or circuits, for signaling operating conditions to heat exchanger230and air conditioner240.

The example ofFIG.2shows a simplified diagram for an example embodiment. Here it can be appreciated that controller200acts to logically control relays210a,210b(which may be a pair of AC power relays and a pair of DC power relays) to communicate power and therefore operation, via terminal blocks, to heat exchanger230and air conditioner240.

As described herein, the lowering of ambient temperature causes controller200to remove power from air conditioner240and supply it, e.g., via DC interchange, to power heat exchanger230using DC. When the temperature rises, heat exchanger230ceases operation and air conditioning unit240operates to take over control of cooling enclosure200or cabinet (not specifically illustrated). Thereafter, on further temperature increase, controller200simulates AC power loss via relay signal to allow heat exchanger230to begin operation in parallel with air conditioner240in the presence of AC power.

Turning toFIG.3, an example device that may be used in implementing one or more embodiments includes a controller200in the form of a microcontroller computing device or a control panel.

Controller300may execute program instructions or code or operate using dedicated circuitry configured to process data or signals and perform other functionality of the embodiments. Components of controller300may include, but are not limited to, a processing unit, which may take a variety of forms such as a central processing unit (CPU)310, a programmable circuit or other programmable hardware, non-programmable hardware, a combination of the foregoing, etc., a system memory controller340and memory350, as well as a system bus322that couples various system components including the system memory350to the processing unit310. It is noted that in certain implementations, controller may take a reduced or simplified form, such as a micro-control unit implemented in a control panel of a cooling system, or even non-programmable hardware such as a series of relays, switches, or circuits, where certain of the components of controller are omitted or combined, or the “controller” is formed by one or more of these other elements.

Controller300may include or have access to a variety of non-transitory computer readable media. Memory350may include non-transitory computer readable storage media in the form of volatile and/or nonvolatile memory devices such as read only memory (ROM) and/or random-access memory (RAM). By way of example, and not limitation, memory350may also include an operating system, application programs, other program modules, and program data. For example, memory350may include application programs such as variable speed control software and/or air conditioner operational software for implementing various cooling protocols, as described herein. Data may be transmitted by wired or wireless communication elements330,320, respectively, e.g., to or from first device to another device, e.g., communication between a remote device or system such as controller300.

A user can interface with (for example, enter commands and information) the controller300through input devices such as a touch screen, keypad, etc. A monitor or other type of display screen or device may also be connected to system bus322via an interface. Controller300may operate in a networked or distributed environment using logical connections to one or more other remote computers or databases. The logical connections may include a network, such local area network (LAN) or a wide area network (WAN) but may also include other networks/buses. In one example, controller300is remotely controllable via Ethernet.

It should be noted that various functions described herein may be implemented using processor executable instructions stored on a non-transitory storage medium or device or using dedicated circuitry or circuits. A non-transitory storage device may be, for example, an electronic, electromagnetic, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of a non-transitory storage medium include the following: a portable computer diskette, a hard disk, a random-access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a solid-state drive, or any suitable combination of the foregoing. In the context of this document “non-transitory” media includes all media except non-statutory signal media.

It is worth noting that while specific elements are illustrated in the figures, and a particular ordering or organization of elements or steps has been illustrated, these are non-limiting examples. In certain contexts, two or more elements or steps may be combined into an equivalent element or step, an element or step may be split into two or more equivalent elements or steps, or certain elements or steps may be re-ordered or re-organized or omitted as appropriate, as the explicit illustrated examples are used only for descriptive purposes and are not to be construed as limiting.