Patent Application
20180017300
The present disclosure relates to devices and systems for refrigeration system operation.
Refrigeration systems can be used in residential and/or commercial environments. When a refrigeration system is operating to remove heat from an enclosed space for the purpose of lowering the temperature, that system can be said to be operating in a “refrigeration mode.” When the refrigeration system is operating to keep one or more of its evaporator coils clear of frost, that system can be said to be operating in a “defrost mode.”
In some cases, defrost mode may include imposing compressor off cycles periodically while the evaporator fan(s) continues to operate. In some cases, evaporator fan(s) can be shut off while defrost heaters are activated to melt accumulated frost off of the evaporator coil surfaces.
Each of the refrigeration mode and the defrost mode can be controlled according to a number of control limits. However, in real-world applications, refrigeration systems do not always operate within those limits. Previous approaches to operating refrigeration systems may not provide information regarding the operation of a refrigeration system with respect to its control limits. Accordingly, previous embodiments may not allow for the efficient management, operation, and or maintenance of refrigeration systems.
Devices and systems for refrigeration system operation are described herein. One or more embodiments include a controller for refrigeration system operation having logic to receive inputs from a temperature sensor over a period of time, the inputs indicating determined temperatures in a refrigeration system over the period of time, compare each of the determined temperatures to control limits, sort the determined temperatures into a plurality of categories based on a relationship between the determined temperatures and the control limits, and cause a user interface to display the sorted determined temperatures.
Embodiments of the present disclosure can be used to inform users (e.g., business owners, maintenance personnel, etc.) about the status, effectiveness, efficiency, and/or health of their refrigeration system(s). For example, embodiments of the present disclosure may be used in a grocery store to improve the operation of refrigeration systems therein. Embodiments of the present disclosure can provide enhanced operating capabilities in both refrigeration mode (e.g., during refrigeration cycle(s)) and defrost mode (e.g., during defrost cycle(s)).
In some embodiments, while a refrigeration system is operating in refrigeration mode, information (e.g., data points, values, etc.) can be determined (e.g., sensed, acquired, collected, etc.) by one or more sensors associated with the refrigeration system. The type of information determined can depend on sensor type and/or component with which the sensor is associated. In an example, a temperature sensor can determine ambient air temperature in an area refrigerated by the refrigeration system. Temperatures can be determined according to a schedule (e.g., once per minute), for instance.
The determined values can be communicated to a management device (e.g., a controller and/or computing device). The management device can compare the determined values to control limits. As referred to herein, control limits are target operating parameters of one or more aspects of a refrigeration system. With regard to temperature, control limits can include target (e.g., desired, set, predetermined, etc.) operating temperatures of the refrigeration system (e.g., set points). For example, control limits can be set such that a refrigerated area is set to be kept in a target temperature range (e.g., 32 to 40 degrees Fahrenheit). Control limits can be set for temperature, pressure, energy usage, and/or flow rates, among other measurable values.
Refrigeration systems may not always operate within control limits. Embodiments of the present disclosure can compare determined information associated with the refrigeration system and compare it to the appropriate control limits. If a determined temperature data point, for instance, falls below a lower control limit, that data point can be sorted into a first category. If a determined temperature data point falls between a lower control limit and an upper control limit (e.g., within control limits), that data point can be sorted into a second category. If a determined temperature data point falls above an upper control limit, that data point can be sorted into a third category. The process can continue for each data point determined by each sensor.
Accordingly, embodiments herein can track measured aspects of refrigeration systems with respect to their control limits. In some embodiments, the categorization of these determined values can allow the provision of user-friendly displays rather than raw data requiring analysis. For instance, a user can be apprised of a percentage of a refrigeration cycle (or a plurality of refrigeration cycles) during which control limits were achieved. Users can take action to modify one or more aspects of the refrigeration system when control limits are not achieved (e.g., not sufficiently achieved).
In some embodiments, action can be taken by the management device directly. For instance, the management device can modify a power level of one or more components of the refrigeration system in order to achieve (or better achieve) the control limits. Such action may be accompanied by a notification, for instance.
In addition to the operation of refrigeration mode, embodiments of the present disclosure can allow for the enhanced operation of refrigeration systems in defrost mode. For instance, a report can be provided that includes a summation of one or more defrost cycles. In some embodiments, the report can include a particular determined temperature that exceeds a threshold for each of the plurality of defrost cycles (e.g., a maximum temperature reached in each cycle), a percentage of defrost cycles in which a termination temperature was reached, and/or a respective temperature determined after a particular period of time following a respective completion of each defrost cycle.
Accordingly, users can be apprised of the status, effectiveness, efficiency, and/or health of their refrigeration system(s), in both refrigeration mode and in defrost mode. Rather than having to analyze raw information and engage in time-consuming data collection, users can be immediately provided with a dashboard-type display that readily communicates the information they may need without overwhelming them with the information they may not.
In the following detailed description, reference is made to the accompanying drawings that form a part hereof. The drawings show by way of illustration how one or more embodiments of the disclosure may be practiced.
These embodiments are described in sufficient detail to enable those of ordinary skill in the art to practice one or more embodiments of this disclosure. It is to be understood that other embodiments may be utilized and that process changes may be made without departing from the scope of the present disclosure.
As will be appreciated, elements shown in the various embodiments herein can be added, exchanged, combined, and/or eliminated so as to provide a number of additional embodiments of the present disclosure. The proportion and the relative scale of the elements provided in the figures are intended to illustrate the embodiments of the present disclosure, and should not be taken in a limiting sense.
The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing. Similar elements or components between different figures may be identified by the use of similar remaining digits.
As used herein, “a” or “a number of” something can refer to one or more such things. For example, “a number of control limits” can refer to one or more control limits.
As shown in
The refrigeration circuit 102 can be a refrigeration system of, for example, a retail store, such as a supermarket or grocery store. The refrigeration circuit 102 can be, for example, a refrigeration and/or freezer display case and/or walk-in cooler of the retail store. For instance, the refrigeration circuit 102 may include a single display case or walk-in cooler, or multiple display cases or walk-in coolers.
It is noted that while one refrigeration circuit (e.g., refrigeration circuit 102) is shown in
A refrigerant can flow (e.g., circulate and/or cycle) through refrigeration circuit 102 in a counterclockwise direction, as indicated in
Condenser 112 can condense (e.g., cool) the refrigerant (e.g., superheated) vapor into a liquid. For example, condenser 112 can include a coil or tubes, and condenser 112 can condense the refrigerant vapor into a liquid by flowing the refrigerant through the coil or tubes while flowing cool water or cool air across the coil or tubes, such that heat from the refrigerant is carried away by the water or air.
The condensed liquid refrigerant can then flow through throttling valve 114 and be received by (e.g., input into) liquid refrigerant receiver 116. That is, throttling valve 114 can be located between condenser 112 and liquid refrigerant receiver 116 (e.g., downstream from condenser 112 and upstream from liquid refrigerant receiver 116), as illustrated in
Liquid refrigerant receiver 116 can be a pressure accumulation vessel that holds (e.g., stores) excess liquid refrigerant present in refrigeration circuit 102. By holding the excess liquid refrigerant, receiver 116 can adjust (e.g., minimize) the active charge of the refrigerant, which can reduce the sensitivity of refrigeration circuit 102 to the refrigerant charge (e.g., to changes in the charge of the refrigerant during operation of the circuit).
Liquid refrigerant receiver 116 can include an upstream port through which the condensed liquid refrigerant enters (e.g., is input), and a downstream port through which the condensed liquid refrigerant exits (e.g., is output). The upstream port can have a nozzle to promote mixing and heat exchange of the input refrigerant within a vapor region, and the downstream port can have a pipe reaching to the bottom of a liquid region.
Before the condensed liquid refrigerant is received by (e.g., enters) liquid refrigerant receiver 116, throttling valve 114 can adjust (e.g., decrease) the pressure of the condensed liquid refrigerant to subcool (e.g., remove heat from) the condensed liquid refrigerant. That is, controller 104 can operate (e.g., adjust) throttling valve 114 to adjust the pressure of the condensed liquid refrigerant to subcool the condensed liquid refrigerant.
Throttling valve 114 can be any type of valve that can obstruct the flow of the condensed liquid refrigerant to adjust (e.g., decrease) its pressure. For example, throttling valve 114 can be a modulating electronic throttling valve. In some embodiments, throttling valve 114 can subcool the condensed liquid refrigerant by a particular (e.g., pre-determined) amount (e.g., a particular number of degrees). That is, throttling valve 114 can control the magnitude of the subcooling occurring in condenser 112. For instance, controller 104 can operate throttling valve 114 to adjust the pressure of the condensed liquid refrigerant by the amount needed to subcool the condensed liquid refrigerant by the particular amount.
The pressure adjustment (e.g., the magnitude of the pressure adjustment) made to the condensed liquid refrigerant by throttling valve 114 can be based (e.g., depend) on the pressure of the condensed liquid refrigerant before it flows through throttling valve 114 (e.g., the pressure of the condensed liquid refrigerant downstream from condenser 112 and upstream from throttling valve 114), and on the pressure of the condensed liquid refrigerant after it exits (e.g., downstream from) liquid refrigerant receiver 116. That is, the adjustment of throttling valve 114 made by controller 104 can be based on the pressure of the condensed liquid refrigerant before it flows through throttling valve 114 and after it exits liquid refrigerant receiver 116. For example, controller 104 can determine the adjustment to throttling valve 114 that will result in the pressure of the condensed liquid refrigerant being adjusted by the amount needed to subcool the condensed liquid refrigerant by the particular amount (e.g., the amount resulting in the greatest possible efficiency increase for refrigeration circuit 102) based on (e.g., using) the pressure of the condensed liquid refrigerant before it flows through throttling valve 114 and after it exits liquid refrigerant receiver 116, and adjust throttling valve 114 accordingly.
In some embodiments, the system 100 can include pressure sensors 122-1 and 122-2, as illustrated in
Controller 104 can communicate with throttling valve 114 and pressure sensors 122-1 and 122-2 (e.g., control the operation of throttling valve 114 and receive sensed pressures from pressure sensors 122-1 and 122-2) via a direct (e.g., wired) connection (e.g., in embodiments in which controller 104 is integrated into the heat pump), or via a wired or wireless network or networks (e.g., in embodiments in which controller 104 is separate from the heat pump). The wireless network(s) can be, for instance, a wide area network (WAN) such as the Internet, a local area network (LAN), a personal area network (PAN), a campus area network (CAN), or metropolitan area network (MAN), among other types of wireless networks.
As used herein, a “network” can provide a communication system that directly or indirectly links two or more computers and/or peripheral devices and allows users to access resources on other computing devices and exchange messages with other users. A network can allow users to share resources on their own systems with other network users and to access information on centrally located systems or on systems that are located at remote locations. For example, a network can tie a number of computing devices together to form a distributed control network.
A network may provide connections to the Internet and/or to the networks of other entities (e.g., organizations, institutions, etc.). Users may interact with network-enabled software applications to make a network request, such as to get a file or print on a network printer. Applications may also communicate with network management software, which can interact with network hardware to transmit information between devices on the network.
Although not shown in
Expansion valve 118 can adjust (e.g., further decrease) the pressure of the condensed liquid refrigerant. That is, expansion valve 118 can be operated by controller 104 (e.g., via a direct connection or a wired or wireless network(s)) to decrease the pressure of the subcooled liquid output from liquid refrigerant receiver 116.
After flowing through the expansion valve 118, the liquid refrigerant can enter the coil or tubes of evaporator 120. A fan can circulate warm air from the enclosed space across the coil or tubes carrying the cold liquid refrigerant, which can cool the air and thus lower the temperature of an enclosed area (e.g., refrigeration rack, etc.). At the same time, the warm air evaporates the liquid refrigerant, so that the refrigerant is once again a saturated vapor. The saturated vapor can exit evaporator 120 and flow to compressor 110, and the cycle can be repeated.
As shown in
In accordance with embodiments herein, the controller 104 can be utilized to monitor values determined by the sensors 122-1, 122-2, 122-3, 124. For example, the controller can receive signals indicating determined data (e.g., sensed temperatures, pressures, etc.) from the number of sensors 122-1, 122-2, 122-3, 124. In some embodiments, the controller 104 can also be utilized to monitor a power consumption for each of the number of electrical devices of the system 100. For example, the controller 104 can be utilized to monitor a power consumption (e.g., real time power usage, etc.) of the compressor 110.
Though four sensors 122-1, 122-2, 122-3, 124 are shown in
Values determined by the sensors of the system 100 can include, for instance, ambient air temperature in the refrigeration circuit (e.g., in an area refrigerated by the refrigeration system), superheat temperature, subcooling temperature, discharge pressure, suction pressure, liquid refrigerant level, liquid refrigerant temperature, flow rate, and/or power consumption, among others.
As referred to herein “sensors” can refer to one or more sensors associated with a refrigeration system and/or associated with one or more components of a refrigeration system.
The controller 104 can receive inputs from the sensors over a period of time. The period of time can coincide with a refrigeration mode of the refrigeration circuit 102 and/or one or more refrigeration cycles of the refrigeration circuit 102. For the purposes of illustration, inputs from a single temperature sensor may be herein discussed, though it is noted that, as previously discussed, embodiments of the present disclosure are not so limited.
The display 226 includes a number of display elements. The display elements can include pull-down menus, input fields, etc. In some embodiments, the display elements can be used to configure refrigeration system operation. As previously discussed, inputs from a temperature sensor can be received by a management device over a period of time, the inputs indicating determined temperatures in the refrigeration system (e.g., the refrigeration circuit 102) over the period of time.
For instance, at 228, a sampling interval can be selected. At 244, control limits for the particular sensor can be selected. In some embodiments, one or more of the control limits can be associated with a setpoint of one or more components of the refrigeration system. In some embodiments, one or more of the control limits can be associated with a deadband of one or more components of the refrigeration system. In some embodiments, one or more of the control limits can be user-determined and/or selected. As shown, the display element 244 includes a field configured to receive a numeric value for each of a lower control limit and an upper control limit.
Once the refrigeration system operation is configured, embodiments of the present disclosure can receive the inputs from the sensor(s) and compare them to the control limits. In the example of the temperature sensor, each of the determined temperatures can be compared to the control limits.
The display 226 can be utilized to view determined values (e.g., during and/or following a refrigeration cycle) and the results of their comparison to the control limits. For instance, at 230, a total number of determined values (temperatures, in this example) can be displayed. As previously discussed, the temperatures can be sorted into a plurality of categories based on a relationship between the determined temperatures and the control limits.
The display 226 can show the sorted determined temperatures. For instance, at 232 a number of determined temperatures falling above the upper control limit can be displayed. At 234, a proportion of those determined temperatures (e.g., a percentage of the total number of determined temperatures) falling above the upper control limit can be displayed. At 236, a number of determined temperatures falling between the upper and lower control limit can be displayed. At 238, a proportion of those determined temperatures (e.g., a percentage of the total number of determined temperatures) falling between the upper and lower control limits can be displayed. At 240, a number of determined temperatures falling below the lower control limit can be displayed. At 242, a proportion of those determined temperatures (e.g., a percentage of the total number of determined temperatures) falling below the lower control limit can be displayed.
By sorting these values and displaying them in proportional form, embodiments herein can allow for the rapid cognition by users of the performance of the refrigeration system. If the system is performing adequately, the proportion of determined temperatures falling between the control limits should be relatively high (e.g., 90% or higher). Embodiments of the present disclosure can display such temperature (or other) values in real-time, for instance, as the corresponding inputs are received from the sensor(s).
At 246, an “inhibit” functionality can be enabled wherein no values are received for a selected period of time. Such functionality may be enabled when determining values associated with a defrost cycle of the refrigeration system (discussed further below).
Embodiments of the present disclosure are not limited to the particular example of the display 226 illustrated in
The display 348 includes a number of display elements. The display elements can include pull-down menus, input fields, etc. In some embodiments, the display elements can be used to configure defrost mode operation. As previously discussed, inputs from a temperature sensor can be received by a management device during one or more defrost cycles, the inputs indicating determined temperatures in the refrigeration system (e.g., the refrigeration circuit 102) during a defrost mode of the refrigeration system. At 350, for instance, a total number of defrost cycles performed can be displayed.
From these inputs, defrost mode operating information can be determined. As described herein, defrost mode operating information can include a particular determined temperature that exceeds a threshold for each of the plurality of defrost cycles. In some embodiments, this can include a maximum temperature reached during each defrost cycle and/or a maximum temperature reached for all defrost cycles. Defrost mode operating information can include a number and/or a proportion of the plurality of defrost cycles in which a termination temperature was reached. Such information can be communicated at 352 and 354, respectively. Defrost mode operating information can include a number and/or a proportion of the plurality of defrost cycles that were terminated on time (e.g., not behind schedule). Such information can be communicated at 356 and 358, respectively. Defrost mode operating information can include a number and/or a proportion of the plurality of defrost cycles that were terminated responsive to user request. Such information can be communicated at 360 and 362, respectively. Additionally, defrost mode operating information can include a respective temperature determined after a particular period of time (e.g., 30 minutes) following the respective completions of the defrost cycles. Such a time period can be selected based on a known time for the refrigeration system to re-enter a refrigeration cycle, for instance.
As shown in
Further, although memory 466, processor 468 and user interface 470 are illustrated as being located in computing device 464, embodiments of the present disclosure are not so limited. For example, memory 466 can also be located internal to another computing resource (e.g., enabling computer readable instructions to be downloaded over the Internet or another wired or wireless connection). Part of the memory 466 can be storage in a cloud storage, for instance. Processor 468 can be a cloud computer.
As shown in
Additionally, computing device 464 can receive information from the user of computing device 464 through an interaction with the user via user interface 470. For example, computing device 464 (e.g., the display of user interface 470) can receive input from the user via user interface 470. The user can enter the input into computing device 464 using, for instance, a mouse and/or keyboard associated with computing device 464, or by touching the display of user interface 470 in embodiments in which the display includes touch-screen capabilities (e.g., embodiments in which the display is a touch screen).
As used herein, “logic” is an alternative or additional processing resource to execute the actions and/or functions, etc., described herein, which includes hardware (e.g., various forms of transistor logic, application specific integrated circuits (ASICs), etc.), field programmable gate arrays (FPGAs), as opposed to computer executable instructions (e.g., software, firmware, etc.) stored in memory and executable by a processor.
Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art will appreciate that any arrangement calculated to achieve the same techniques can be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments of the disclosure.
It is to be understood that the above description has been made in an illustrative fashion, and not a restrictive one. Combination of the above embodiments, and other embodiments not specifically described herein will be apparent to those of skill in the art upon reviewing the above description.
The scope of the various embodiments of the disclosure includes any other applications in which the above structures and methods are used. Therefore, the scope of various embodiments of the disclosure should be determined with reference to the appended claims, along with the full range of equivalents to which such claims are entitled.
In the foregoing Detailed Description, various features are grouped together in example embodiments illustrated in the figures for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the embodiments of the disclosure require more features than are expressly recited in each claim.
Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separate embodiment.
