JP2017161128A - Management device for plural pieces of freezing/refrigerating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a management device capable of performing pressure setting to a refrigerating machine to which plural pieces of freezing and refrigerating equipment are connected without depending on an expert engineer.SOLUTION: There is provided a management device used for a refrigeration cycle in which a discharged refrigerant of a compressor is supplied to use side heat exchangers incorporated into each of the plural pieces of freezing/refrigerating equipment through at least a heat source side heat exchanger and a refrigerant pipe. The management device comprises: an acquisition part for acquiring information on the kind of the refrigerant used in the refrigeration cycle, a connection state of the refrigerant pipe, and uses of the plural pieces of freezing/refrigerating equipment; and a control part for determining a control target range of refrigerant evaporation pressure at each of the use side heat exchangers on the basis of the information on the kind of the refrigerant used in the refrigeration cycle, the connection state of the refrigerant pipe and the uses of the plural pieces of freezing/refrigerating equipment, which is acquired at a communication part.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a management device for a plurality of refrigeration / refrigeration equipment.

  Conventionally, as this type of management apparatus, for example, there is a centralized management system described in Patent Document 1 and the like. In Patent Document 1, a plurality of showcases (in other words, a plurality of refrigeration / refrigeration devices) are provided separately from the refrigerator. A refrigerator supplies the refrigerant | coolant discharged from the common compressor to the evaporator incorporated in the corresponding showcase through a condenser. The centralized management system controls the capacity of the refrigerator by setting the refrigerant suction pressure of the compressor based on the operation status information for each showcase, the refrigerant pressure, and the inherent pressure loss value.

JP 2007-147184 A

  The set temperature of each showcase may differ depending on the application (in other words, the object to be cooled). Therefore, in order to set the temperature in the showcase (hereinafter referred to as the internal temperature) to the set temperature, it is necessary to appropriately control the evaporation pressure. Therefore, conventionally, a skilled engineer first calculates the blowing temperature based on the application and set temperature for each showcase, and then optimizes the refrigerator pressure setting based on the minimum blowing temperature and refrigerant type. The value was calculated.

  However, the calculation of the blowout temperature and the pressure set value requires highly specialized knowledge such as the specifications of the equipment installed in the store and the operating principle of the refrigerator.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a management device capable of setting the pressure of a refrigerator connected to a plurality of refrigeration / refrigeration equipment without relying on a skilled engineer.

  One aspect of the present invention is a refrigeration cycle in which refrigerant discharged from a compressor is supplied to a use side heat exchanger incorporated in each of a plurality of refrigeration / refrigeration equipment through at least a heat source side heat exchanger and a refrigerant pipe. It is a management device used, and is acquired by the communication unit, an acquisition unit that acquires information on the type of refrigerant used in the refrigeration cycle, the connection state of the refrigerant piping, and uses of the plurality of refrigeration / refrigeration devices. In addition, based on information on the type of refrigerant used in the refrigeration cycle, the connection state of the refrigerant pipes, and the uses of the plurality of refrigeration / refrigeration equipment, the control target range of the evaporation pressure of the refrigerant in each use-side heat exchanger And a control unit that determines the control unit.

  According to the said form, the management apparatus which can implement the pressure setting of the refrigerator to which the several freezing / refrigeration equipment was connected can be provided without relying on a skilled engineer.

It is a figure which shows the refrigerator which the management apparatus which concerns on one Embodiment of this invention, and the some freezing / refrigeration apparatus used as the management object were connected. It is a figure which shows the detailed structure of the refrigerator with which the some freezing / refrigeration apparatus of FIG. 1 was connected. It is a figure which shows the temperature sensor and control circuit in the refrigerator to which the some freezing / refrigeration apparatus of FIG. 1 was connected. It is a figure which shows the detailed structure of the management apparatus of FIG. It is a figure which shows the structure of the control circuit etc. of the showcase of FIG. It is a flowchart which shows the first half part of the process of the management apparatus of FIG. FIG. 6 is a flowchart showing the latter half of the process of the management apparatus of FIG. 5.

<< 1. Embodiment >>
Below, with reference to the said drawing, the refrigerator 2 and the freezing / refrigeration apparatus 3 used as the management object of the management apparatus MC which concerns on one Embodiment of this invention are demonstrated first.

<< 1-1. Configuration of refrigerator and refrigeration equipment >>
In FIG. 1, in a store CVS (for example, a convenience store), a typical example of at least one refrigerator 2 and a plurality of refrigerators / refrigerators 3 mainly for storing products such as foods and beverages at low temperatures. Are connected by a plurality of refrigerant pipes 4. Since the showcase is a typical example of the refrigeration equipment 3, hereinafter, the showcase will be denoted by reference numeral 3. In FIG. 1, reference numeral 2 is attached to one refrigerator, and reference signs 3a, 3b, and 3c are attached to three showcases. Although other showcases are shown in the store CVS, these are also connected to other refrigerators, for example, by refrigerant piping.

  FIG. 1 further shows a management device MC for managing the refrigerator 2 and each showcase 3, which will be described in detail later with reference to FIG.

  The refrigerator 2 is installed, for example, outside the store CVS (rooftop or the like), and roughly, as shown in FIG. 2, a compressor 21, a heat source side heat exchanger (condenser) 22, and a refrigerator side Fan (hereinafter also referred to as a first fan) 23, and a control circuit 24.

  Each showcase 3 is a freezing / refrigeration apparatus that is installed inside the store CVS and that refrigerates or freezes a predetermined type of product at a set temperature. The set temperature varies depending on the application (that is, the product to be cooled) as illustrated in Table 1 below.

  As shown in FIG. 2, each showcase 3 generally includes a use side heat exchanger (evaporator) 31, a showcase side fan (hereinafter also referred to as a second fan) 32, and a display. And a shelf 33.

  In the refrigerant pipe 4, an expander 41 is provided at an intermediate position between the heat source side heat exchanger 22 and each use side heat exchanger 31 (more specifically, immediately upstream of each use side heat exchanger 31). One by one.

The refrigerant (for example, CO ₂ refrigerant) discharged from the use side heat exchanger 31 of the showcase 3 is sucked into the compressor 21 through the refrigerant pipe 4. The compressor 21 compresses the sucked refrigerant and discharges it to the refrigerant pipe 4 toward the condenser 22. High-temperature and high-pressure refrigerant discharged from the compressor 21 is sent to the inlet of the condenser 22 via the refrigerant pipe 4. The heat source side condenser 22 passes the fed refrigerant and discharges it from the outlet to the refrigerant pipe 4. Further, cooling fins (not shown) are provided around the heat source side condenser 22 at intervals. The heat of the refrigerant passing through the heat source side condenser 22 is released from the cooling fins. Further, the heat emitted from the heat source side condenser 22 is released to the outside of the refrigerator 2 by the air flow generated by the first fan 23.

  In the refrigerant pipe 4, the expander 41 expands and depressurizes the refrigerant cooled by the heat source side heat exchanger 22, and discharges it to the refrigerant pipe 4. Moreover, each use side heat exchanger 31 evaporates the refrigerant decompressed by the expander 41 to cool the ambient air. The cooled air is sent to the display shelf 33 by the air flow generated by the second fan 32. Thereby, the product group placed on the display shelf 33 is cooled.

<< 1-2. Temperature sensors for refrigerators and refrigeration equipment >>
Further, as shown in FIG. 3, a temperature sensor Se1 made of, for example, a thermistor is attached to each showcase 3. The temperature sensor Se <b> 1 detects the evaporation temperature in the use side heat exchanger 31 and outputs a signal indicating the detection result to the control circuit 24.

<< 1-3. Control circuit >>
As shown in FIG. 3, the control circuit 24 includes a microcomputer, a nonvolatile memory, and a storage unit (for example, SRAM). The microcomputer executes the program stored in the nonvolatile memory by using the storage unit as a work area to control the internal temperature.

  Next, control of the internal temperature will be described with reference to FIG. The control circuit 24 controls the operation of the compressor 21 so that an appropriate evaporating pressure is continuously obtained in the use side heat exchanger 31. However, in practice, it is difficult to stably obtain the evaporation pressure, and the evaporation pressure deviates from the target value (that is, an appropriate evaporation pressure). In this embodiment, a differential value, an on value, and an off value are defined for the evaporation pressure in order to operate the compressor 21 so that the deviation is reduced and the evaporation pressure is as close as possible to the target value.

The differential value is a value indicating how much deviation between the target value of the evaporation pressure and the actual evaporation pressure is allowed.
The ON value is a value obtained by converting the upper limit value of the allowable evaporation pressure into a temperature, and is converted into a temperature from an addition value of the target value of the evaporation pressure and the differential value.
The off value is a value obtained by converting a lower limit value of an allowable evaporation pressure into a temperature, and is converted into a temperature from a value obtained by subtracting a differential value from a target value of the evaporation pressure.

  When the control circuit 24 receives the output signal of the temperature sensor Se1 of the showcase 3 with the lowest blowing temperature during refrigeration / freezing of the product, and determines that the current evaporation pressure has reached the ON value based on the received signal, The operation of the compressor 21 is started, and the refrigerant is started to be compressed. On the other hand, when it is determined that the current evaporation pressure has reached the OFF value, the operation of the compressor 21 is stopped. With this control, in the refrigeration cycle including the refrigerator 2 and the showcase 3, “evaporation pressure reaches an on value” → “start of refrigerant compression” → “decrease in evaporation pressure” → “evaporation pressure decreases to an off value” ”→“ Stop refrigerant compression ”→“ Evaporation pressure rise ”→“ Evaporation pressure reaches ON value ”→... As a result, the evaporation pressure changes around the target value.

  In the present embodiment, the on value and the off value can be dynamically adjusted in accordance with the cooling state of the showcase 3 in order to improve the energy saving performance. That is, when the refrigeration load in the showcase 3 decreases, the OFF value is increased by a predetermined amount so that the operation of the compressor 21 can be easily stopped. This enhances energy saving performance. Conversely, when the refrigeration load increases, the ON value is decreased by a predetermined amount.

<< 1-4. Configuration of management device >>
As described above, the set temperature of each showcase 3 is different for each application, and the connection state of the refrigerant pipe 4 is different for each store CVS. Therefore, the appropriate evaporation pressure differs for each store CVS. The calculation of the blowout temperature and the pressure set value requires advanced expertise such as the specifications of the equipment installed in the store and the operating principle of the refrigerator. Therefore, there is a demand from the market for a management device MC that can easily set the pressure of the refrigerator 2 to which a plurality of showcases 3 are connected without relying on advanced expertise.

  The management device MC is, for example, a terminal device in which the refrigerator 2 and the showcase 3 are carried by an engineer involved in the installation of the store CVS, and as shown in FIG. 4, a communication unit 51, a program memory 52, , A work area 53, a processor 54 as a control unit, an input device 55, and a display 56.

  The communication unit 51 communicates with the refrigerator 2 and the showcase 3 via a wired or wireless communication network. The program memory 52 is, for example, a nonvolatile memory, and stores a program P. The work area 53 is, for example, a RAM. The processor 53 executes the program P while using the work area 53, and automatically sets the pressure of the refrigerator 2 to which the plurality of showcases 3 are connected based on various information acquired through the communication unit 51. .

  The input device 55 is a keyboard, a touch panel, or the like provided in the housing of the management device MC. The display 56 is a liquid crystal display, a touch panel, or the like provided in the casing of the management device MC.

  As shown in FIG. 3, the refrigerator 2 includes a communication unit 25 in addition to the control circuit 24 in order to communicate with the management device MC. Each showcase 3 further includes a control circuit 34 that stores various types of information in an internal nonvolatile memory and a communication unit 35, as shown in FIG. The various information includes information on the type of refrigerant used in the showcase 3 in addition to the information indicating the volume, usage, presence / absence of a door, and set temperature of the corresponding showcase 3.

<< 1-5. Operation of management device >>
Next, the operation of the management device MC will be described in detail with reference to FIGS. 6A and 6B.
When it is necessary to set the pressure of the refrigerator 2 to which a plurality of showcases 3 are connected, the engineer starts up the program P of the management device MC in the store CVS.

  First, the engineer operates the input device 55 to establish communication between the management device MC and each showcase 3 (step S001 in FIG. 6A). Thereafter, the engineer operates the input device 55 to instruct the management device MC to recognize the showcase 3 connected via the communication network (step S002). In the management device MC, the processor 54 Each showcase 3 is communicated with each other via the communication unit 51 to recognize each (step S003). Thereafter, the processor 54 receives various information from each showcase 3 (step S004).

  The engineer visually confirms the refrigerant piping 4 connecting the plurality of showcases 3 and the refrigerator 2 and operates the input device 55 to input information (length, etc.) of the refrigerant piping 4 in units of sections. . Thereby, the processor 54 acquires the information of the refrigerant | coolant piping 4 (step S005). Here, the section of the refrigerant pipe 4 is a part of the refrigerant pipe 4 that connects a plurality of elements, such as the refrigerant pipe 4 between the compressor 21 and the heat source side heat exchanger 22.

  Next, the processor 54 selects one of the plurality of showcases 3 (step S006), and obtains the blowout set temperature for the selected showcase 3 from the use and the set temperature acquired in step S004 (step S006). S007). The process of step S007 is repeated until all the showcases 3 are selected in step S006 (step S008).

  If it is determined in step S008 that step S007 has been executed for all the showcases 3, the processor 54 selects the minimum value from the calculated blowing preset temperatures (step S009).

  Next, the processor 54 calculates the evaporation temperature required in the use side heat exchanger 31 from the minimum value of the blowing set temperature selected in step S009 and the corresponding use of the showcase 3 (in FIG. 6B). Step S010).

  Next, the processor 54 calculates a differential value and an evaporation pressure from the evaporation temperature calculated in step S010, the refrigerant used, and the information of the refrigerant pipe 4 acquired in step S005 (step S011). At this time, if the corresponding showcase 3 has a door, the calculated evaporation pressure is preferably increased by a predetermined value.

  Next, the processor 54 calculates an ON value and an OFF value of the evaporation pressure as an example of the pressure setting value from the differential value calculated in Step S011 and the evaporation pressure (Step S012).

  Next, the processor 54 preferably calculates an upper limit value and a lower limit value for each of the ON value and the OFF value of the evaporation pressure calculated in step S012 based on the cooling capacity of the refrigerator 3 (step S013).

  The processor 54 transmits the ON value and OFF value of the evaporation pressure obtained in steps S012 and S013 and the upper and lower limits for adjustment to the control circuit 24 of the refrigerator 2 via the communication unit 51. And display on the display 56 (step S014). In the refrigerator 2, the control circuit 24 sets reception information in an internal nonvolatile memory.

<< 1-6. Action / Effect >>
As described above, according to the present management apparatus MC, an appropriate pressure set value is calculated by inputting the use of each showcase 3 and information on the refrigerant pipe 4 unique to the store CVS. As a result, it is possible to provide a management device MC capable of setting the pressure of the refrigerator 2 to which a plurality of refrigeration / refrigeration equipments 3 are connected without relying on skilled engineers.

<< 1-7. Appendix >>
In the above description, the management apparatus MC has been described as acquiring various types of information from each showcase 3 by communication. However, the present invention is not limited to this, and various information linked to the ID information of each showcase 3 is stored in advance in the nonvolatile memory or the like of the management device MC, and the control circuit 24 stores the various information stored in advance. On the basis of the pressure setting value, an on value and an off value of the evaporation pressure may be calculated.

  The management device according to the present invention can set the pressure of a refrigerator to which a plurality of refrigeration / refrigeration equipments are connected without relying on a skilled engineer, and is suitable for a stand-alone showcase or the like.

MC management device 51 communication unit 54 control unit (processor)

Claims (2)

A management device used in a refrigeration cycle for supplying refrigerant discharged from a compressor to at least one of a plurality of refrigeration / refrigeration equipment built-in heat exchangers via at least a heat source side heat exchanger and a refrigerant pipe. ,
An acquisition unit that acquires information on the type of refrigerant used in the refrigeration cycle, the connection state of the refrigerant pipes, and uses of the plurality of refrigeration / refrigeration equipments;
Based on information on the type of refrigerant used in the refrigeration cycle acquired by the communication unit, the connection state of the refrigerant pipes, and the use of the plurality of refrigeration / refrigeration equipment, the refrigerant in each usage-side heat exchanger A control unit that determines a control target range of the evaporation pressure. A storage unit for storing the type of refrigerant used in the refrigeration cycle, the connection state of the refrigerant pipes, and uses of the plurality of refrigeration / refrigeration equipment;
The management device according to claim 1, wherein the acquisition unit acquires from the storage unit the type of refrigerant used in the refrigeration cycle, the connection state of the refrigerant piping, and uses of the plurality of refrigeration / refrigeration equipment.

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