Support System and Support Method

The present application is a bypass continuation of International Application PCT/JP2023/047348, filed Dec. 28, 2023, which claims priority to Japanese patent application 2023-000693, filed Jan. 5, 2023, the entire contents of each of which being incorporated herein by reference.

The present disclosure relates to a support system and a support method.

A method is desired for selecting an optimal refrigerant system when a refrigerant system installed in a building and to which an air conditioner and a refrigerant pipe belong is updated. Patent Literature 1 (JP H08-94150 A) discloses, as a system in which an air conditioner belonging to a refrigerant system is selected, a system in which a heat load for cooling and heating of each room in which an air conditioner is installed is calculated based on data related to the air conditioning design of a building, and an air conditioner to be installed in each room is selected based on the calculation result.

While this may ensure that the selected equipment has sufficient capacity for the thermal load, there is still a need to ensure that a refrigerant system complies with modern safety standards with respect to a maximum allowable refrigerant charge.

The present disclosure addresses the foregoing and other technical problems by providing a support system with a specifically programmed control unit that improves the functioning of the computer itself. By integrating system information, component specifications, and safety standards, the system transforms a general-purpose computer into a specialized design and optimization tool for refrigerant system updates.

A support system of a first aspect supports update of a refrigerant system to which an outdoor unit, an indoor unit, and a refrigerant pipe connecting the outdoor unit and the indoor unit belong. The support system includes a control unit. The control unit performs the following processing.

A first amount, which is an amount of refrigerant charged in a refrigerant system after update, is calculated based on information related to at least one of the outdoor unit, the indoor unit, and the refrigerant pipe belonging to a refrigerant system before update.

A second amount, which is the maximum allowable amount of refrigerant charged in the refrigerant system after update or the maximum amount of refrigerant allowed to be retained in a room when the refrigerant leaks into the room from the indoor unit and the refrigerant pipe belonging to the refrigerant system after update, is acquired.

Update of a refrigerant system is supported by presenting, as information related to the refrigerant system after update, information related to a refrigerant system in which the calculated first amount does not exceed the acquired second amount.

A support systemof the present embodiment is a system for supporting update of a refrigerant system. The update of a refrigerant system is the work of replacing a refrigerant system existing in a building with a new one. For example, supporting the update of a refrigerant system is presenting information related to the refrigerant system after update selected based on a predetermined condition to a person, or presenting candidates for the refrigerant system after update to a person for the person to select the refrigerant system after update. For example, the predetermined condition is a safety standard requirement based on a law or the like.

The refrigerant system means the configuration of a refrigeration system. In the present embodiment, the refrigeration system is an air conditioning systemin which a plurality of outdoor unitsand a plurality of indoor unitsare connected via a refrigerant pipe. In this case, the refrigerant system of the air conditioning systemincludes a connection state related to which outdoor unitand which indoor uniteach refrigerant pipeconnects. In the refrigerant system of the air conditioning system, one outdoor unitis connected to one or a plurality of indoor unitsvia the refrigerant pipe. Further, the refrigerant system includes device information related to the devices configuring the refrigeration system. For example, the device information includes the model and capacity of the outdoor unitand the indoor unitbelonging to the refrigerant system, and the diameter and length of the refrigerant pipebelonging to the refrigerant system.

As shown in, for example, the air conditioning systemis installed in a propertyhaving a plurality of rooms. The propertyis a building such as an office building. The air conditioning systemhaving a plurality of refrigerant systems is installed in the property. Each refrigerant system is a package-type air conditioner including one outdoor unitand a plurality of indoor units. The outdoor unitis an air conditioning unit including a compressor, a heat exchanger, an expansion mechanism, a fan, and the like. The outdoor unitis installed outside the property. The indoor unitis an air conditioning unit including a heat exchanger, a fan, and the like. The indoor unitis installed in the roomin the property. The roomis a space to be the target of air-conditioning by the air conditioning system. One or a plurality of indoor unitsis installed in one room. The outdoor unitand the indoor unitconstitute a refrigerant circuit by being connected by the refrigerant pipe. A refrigerant circulates in the refrigerant circuit. When the air conditioning systemincludes a plurality of refrigerant systems, the refrigerant circuits of the respective refrigerant systems are independent of each other.

The support systemis used to support the update of a refrigerant system of the air conditioning systeminstalled in the property. For example, a person in charge of construction work of the propertyperforms construction of updating the refrigerant system of the air conditioning systeminstalled in the propertybased on the information related to the refrigerant system after update presented by the support system. In this case, the person in charge of construction work changes the connection state of the refrigerant system or changes the devices belonging to the refrigerant system.

Further, for example, a person in charge of construction of the propertyselects one refrigerant system based on a predetermined criterion from among a plurality of candidates for the refrigerant system after update presented by the support system, and performs construction of updating the refrigerant system of the air conditioning systeminstalled in the propertybased on the selected refrigerant system. In this case, based on the selected refrigerant system, the person in charge of construction connects the outdoor unitand the indoor unitby the refrigerant pipeand selects the outdoor unit, the indoor unit, and the refrigerant pipebelonging to the refrigerant system.

is a block diagram showing the overall configuration of the support system. The support systemmainly includes a computerand an external input device. The person in charge of construction of the propertycan input information related to a predetermined safety standard requirement by using the computerand the external input device.

The computermainly includes a communication unit, a control unit, a storage unit, an output unit, and an input unit. For example, the computeris a laptop personal computer.

The communication unitis an interface for a communication network and an external device. For example, the communication unitis a network interface for connecting the computerto a communication network such as the Internet, and a general-purpose interface for connecting the computerto an external device such as a printer.

The control unitis mainly configured of a central processing unit (CPU) or processor. The control unitexecutes a calculation unit, a first acquisition unit, a first determination unit, and a support unit. These units correspond to functions realized by a program executed by the control unit. As used herein, the control unitand constituent units therein refers to circuitry that may be configured via the execution of computer readable instructions, and the circuitry may include one or more local processors (e.g., CPU's), and/or one or more remote processors, such as a cloud computing resource, or any combination thereof.

The storage unitis mainly configured of a storage device such as a RAM, an HDD, an SSD, and other types of memory. The storage unitstores a program executed by the control unit, data used by the program, and the like. The storage unitstores charged refrigerant amount information, allowable refrigerant amount information, and support information

The output unitis an output device of the computer, such as a display and a printer. On the display that is the output unit, for example, an interface for starting processing of a program executed by the control unit, a processing result of the program executed by the control unit, and the like are displayed.

The input unitis an input device of the computer, such as a keyboard and a mouse. A user of the support systemwho is a person in charge of construction work of the property, a person in charge of construction, or the like can input, by operating the input unit, information necessary for processing executed by the support system.

For example, the output unitand the input unitmay be integrally configured as a display with a touch panel function and a speaker function.

For example, the external input deviceis a camera and an image scanner. The external input deviceis connected to the communication unitof the computer. The external input devicecan transmit data to the computervia the communication unit.

In the following description, when the air conditioning systemincludes a plurality of refrigerant systems, the control unitexecutes processing for each refrigerant system. Next, details of each function of the control unitand processing executed by the control unitwill be described with reference to the flowchart of.

The calculation unitcalculates a charged refrigerant amount (first amount), which is the amount of refrigerant charged in the refrigerant system after update, based on the system information of the refrigerant system before update of the air conditioning system(step Sin). The charged refrigerant amount calculated by the calculation unitis the amount of refrigerant required for the refrigerant system after update, and is the amount of refrigerant that can be theoretically charged in the refrigerant system after update. The charged refrigerant amount calculated by the calculation unitis saved in the storage unitas the charged refrigerant amount information. The charged refrigerant amount is calculated and stored in kilograms.

The system information of the refrigerant system is information related to at least one of the outdoor unit, the indoor unit, and the refrigerant pipebelonging to the refrigerant system. The system information includes the capacity and specifications of the outdoor unitand the indoor unit, the number of indoor units, and the dimensions (length and diameter) of the refrigerant pipe. For example, the specifications of the outdoor unitand the indoor unitare the volume of the compressor of the outdoor unitand the volumes of the refrigerant flow paths of the heat exchangers of the outdoor unitand the indoor unit. Alternatively, the specifications of the outdoor unitand the indoor unitmay be a refrigerant charging amount that is set in advance for each model of the outdoor unitand the indoor unitinstead of the volumes. The system information further includes information related to which outdoor unitand which indoor uniteach refrigerant pipeconnects, the capacity of the roomin which each indoor unitis installed, and information related to the position and orientation of the indoor unitinstalled in each room.

The system information of the refrigerant system before update is stored in the storage unitin advance. The system information may be stored in advance by being input by the user of the support systemvia the input unitand saved in the storage unit. The system information is stored in advance by being acquired by the control unitbased on predetermined data and saved in the storage unit. For example, the control unitmay acquire the length of the refrigerant pipeincluded in the system information based on drawing data including information related to the installation position of the refrigerant pipein the property.

The storage unitfurther stores, in advance, update information used to determine the refrigerant system after update. For example, the update information is information related to the outdoor unit, the indoor unit, and the refrigerant pipethat can be used in the refrigerant system after update.

The calculation unitcalculates the same amount as the amount of refrigerant charged in the refrigerant system before update as the charged refrigerant amount. In this case, the calculation unitcalculates the amount of refrigerant charged in the refrigerant system before update based on the system information of the refrigerant system before update stored in the storage unit, and adopts the calculated amount as the charged refrigerant amount.

The calculation unitmay calculate the charged refrigerant amount by using the update information stored in the storage unit. In this case, the calculation unituses the update information and determines a temporary refrigerant system charged with the same amount of refrigerant as the amount of refrigerant charged in the refrigerant system before update, and calculates the amount of refrigerant charged in the temporary refrigerant system as the charged refrigerant amount.

The calculation unitmay calculate, as the charged refrigerant amount, an amount smaller by a predetermined amount than the amount of refrigerant charged in the refrigerant system before update. In this case, the calculation unituses the update information and determines a temporary refrigerant system charged with a smaller amount of refrigerant than the amount of refrigerant charged in the refrigerant system before update, and calculates the amount of refrigerant charged in the temporary refrigerant system as the charged refrigerant amount. For example, the amount smaller than the amount of refrigerant charged in the refrigerant system before update is acquired by the calculation unitbased on the target value of charged refrigerant amount stored in the storage unit. For example, the target value of charged refrigerant amount is input by the user of the support systemvia the input unitand stored in the storage unit.

In this way, the calculation unitcalculates a charged refrigerant amount, which is the amount of refrigerant charged in the refrigerant system after update, based on the system information of the refrigerant system before update.

In the following description, it is assumed that the calculation unitinitially calculates the amount of refrigerant charged in the refrigerant system before update as the charged refrigerant amount without using the update information.

The first acquisition unitacquires an allowable refrigerant amount (second amount), which is the maximum allowable amount of refrigerant charged in the refrigerant system after update of the air conditioning system. The first acquisition unitacquires the allowable refrigerant amount after the calculation unitcalculates the charged refrigerant amount (step Sin). The allowable refrigerant amount acquired by the first acquisition unitis the maximum value of the amount of refrigerant that can be used by the refrigerant system after update. The first acquisition unitacquires the allowable refrigerant amount, based on the allowable refrigerant amount informationstored in the storage unit. The allowable refrigerant amount is calculated and stored in kilograms.

The allowable refrigerant amount is stored in advance in the storage unitas the allowable refrigerant amount information. The allowable refrigerant amount informationmay be stored in advance by being input by the user of the support systemvia the input unitand saved in the storage unit.

The allowable refrigerant amount is set based on the predetermined safety standard requirement. For example, the allowable refrigerant amount is the maximum refrigerant amount defined by ISO 5149, which is an international standard for safe design, operation, and the like of refrigerating systems. Part 1 of ISO 5149 defines the maximum refrigerant amount, which is an upper limit value of the total amount of refrigerant that can be charged in one refrigerant system, for the purpose of taking appropriate safety measures in the event of refrigerant leakage. The maximum refrigerant amount (kg) defined in ISO 5149 is a value calculated by 195×LFL. LFL (kg/m) is a lower flammability limit of refrigerant charged in the refrigerant system. The lower flammability limit of refrigerant is a lower limit value of the concentration of refrigerant in a flammable range. In the flammable range, a mixture of refrigerant and air is flammable or ignitable. The LFL of a refrigerant is defined in ISO 817 according to the type of refrigerant based on the toxicity and flammability of the refrigerant. For example, since the LFL of R32 is 0.307 kg/min dry condition (23° C., 50% RH), the maximum refrigerant amount of R32 is 59.8 kg. Therefore, the allowable refrigerant amount of the refrigerant system charged with R32 as the refrigerant is 59.8 kg.

The first acquisition unitmay acquire the allowable refrigerant amount of a refrigerant system after update based on the type of refrigerant charged in the refrigerant system after update and the maximum refrigerant amount defined in ISO 5149.

The first determination unitdetermines whether the update content of the refrigerant system needs to be reviewed based on the charged refrigerant amount calculated by the calculation unitand the allowable refrigerant amount of the refrigerant system acquired by the first acquisition unit. The update content of the refrigerant system includes information related to the charged refrigerant amount calculated by the calculation unit

To be specific, the first determination unitdetermines whether the charged refrigerant amount exceeds the allowable refrigerant amount (step Sin). When the charged refrigerant amount calculated by the calculation unitexceeds the allowable refrigerant amount, the first determination unitdetermines that the update content of the refrigerant system needs to be reviewed such that a charged refrigerant amount that does not exceed the allowable refrigerant amount is calculated. In this case, the calculation unitreviews the update content of the refrigerant system by recalculating the charged refrigerant amount by a method different from the previous method (step S′ in). For example, the calculation unitcalculates, as the charged refrigerant amount, an amount of refrigerant that is a smaller amount than the amount of refrigerant charged in the refrigerant system before update, using the update information. The first determination unitperforms the same determination processing as the previous time after the calculation unitrecalculates the charged refrigerant amount and reviews the update content of the refrigerant system (step Sin).

When the charged refrigerant amount calculated by the calculation unitdoes not exceed the allowable refrigerant amount, the first determination unitdetermines that the update of the refrigerant system can be supported based on the charged refrigerant amount calculated by the calculation unitsince it is not necessary to review the update content of the refrigerant system.

When the first determination unitdetermines that the charged refrigerant amount calculated by the calculation unitdoes not exceed the allowable refrigerant amount, the support unitsupports the update of the refrigerant system based on the charged refrigerant amount calculated by the calculation unitand the allowable refrigerant amount acquired by the first acquisition unit(step Sin). The support unitsupports the update of the refrigerant system by presenting information related to candidates for the refrigerant system after update. For example, the support unituses the update information stored in the storage unitand determines the model, position, and number of the outdoor unitand the indoor unitsbelonging to the refrigerant system after update, and the position, number, and dimensions of the refrigerant pipes, and generates and presents information related to candidates for the refrigerant system after update. The information related to candidates for the refrigerant system after update presented by the support unitis saved in the storage unit.

The support unitpresents information related to a refrigerant system in which the charged refrigerant amount does not exceed the allowable refrigerant amount as a candidate for the refrigerant system after update. A refrigerant system in which the charged refrigerant amount exceeds the allowable refrigerant amount does not satisfy the predetermined safety standard requirement based on the international standard, and is not presented by the support unitas a candidate for the refrigerant system.

Further, the support unitpresents, as a candidate for the refrigerant system after update, a refrigerant system in which the charged refrigerant amount does not exceed the allowable refrigerant amount and which has at least a predetermined required capacity. The system information of the refrigerant system before update stored in advance in the storage unitincludes the capacity of the outdoor unitand the indoor unitbelonging to the refrigerant system before update (capacity before update). The control unitacquires the cooling and heating capacity of the refrigerant system before update based on the capacity before update stored in the storage unitand determines the predetermined required capacity based on the cooling and heating capacity. For example, the control unitdetermines the predetermined required capacity to be the same value as the cooling and heating capacity of the refrigerant system before update, or sets the predetermined required capacity to be a value lower than the cooling and heating capacity of the refrigerant system before update.

The support unitpresents information related to candidates for the refrigerant system after update and supports the update of the refrigerant system by executing first support processing or second support processing described below. In particular, the support unitsupports the update of the refrigerant system by presenting information related to proposed post-update refrigerant system configurations. The user of the support systemselects a refrigerant system after update from among the candidates for the refrigerant system presented by the support unitand updates the refrigerant system of the air conditioning system.

The support unitmay preferentially execute the first support processing over the second support processing. The support unitmay determine which processing of the first support processing and the second support processing is to be executed in consideration of the feasibility and cost of the first support processing and the second support processing.

Information obtained by the support unitexecuting the first support processing or the second support processing is saved in the storage unitas the support information. The support unitpresents the support informationby outputting it via the output unit. The user of the support systemupdates the refrigerant system of the air conditioning system, based on the information presented by the support unit. Next, specific examples of the first support processing and the second support processing will be described.

The support unitthat executes the first support processing presents, as the information related to candidates for the refrigerant system after update, information necessary for the user of the support systemto replace, add, or remove a component of the refrigerant system at the time of update. The component of the refrigerant system is at least one of the outdoor unit, the indoor unit, and the refrigerant pipebelonging to the refrigerant system.

The support unitselects a component to be the target of replacement, addition, or removal at the time of update from among the components of the refrigerant system before update and a component to be the target of replacement or addition at the time of update from among the components of a candidate for the refrigerant system after update, based on the information related to candidates for the refrigerant system after update. Thereafter, the support unitpresents information related to the selected component.

The support unitmay output a plurality of candidate refrigerant systems in descending order of a predetermined indicator value of refrigerant system. The indicator value is a parameter serving as a reference when the user of the support systemselects a refrigerant system. For example, the indicator value is a parameter that increases as the cost required for update of a refrigerant system decreases. The support unitmay select a refrigerant system of which the indicator value is equal to or greater than a predetermined value, and present the refrigerant system as a candidate for the refrigerant system. For example, the cost required for update of a refrigerant system is calculated by the control unitfrom the system information of the refrigerant system.

Next, specific examples of processing in which the support unitpresents candidates for a refrigerant system in which at least a part of the outdoor unitand the indoor unithas been changed, and processing in which the support unitpresents candidates for a refrigerant system in which at least a part of the refrigerant pipehas been changed, will be described. The support unitexecutes at least one of these two kinds of processing.