KR20170087677A - Control system for refrigeration showcase - Google Patents

Control system for refrigeration showcase Download PDF

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Publication number
KR20170087677A
KR20170087677A KR1020160007542A KR20160007542A KR20170087677A KR 20170087677 A KR20170087677 A KR 20170087677A KR 1020160007542 A KR1020160007542 A KR 1020160007542A KR 20160007542 A KR20160007542 A KR 20160007542A KR 20170087677 A KR20170087677 A KR 20170087677A
Authority
KR
South Korea
Prior art keywords
temperature
sensor
refrigerating
evaporator
compressor
Prior art date
Application number
KR1020160007542A
Other languages
Korean (ko)
Inventor
김주옥
Original Assignee
김주옥
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 김주옥 filed Critical 김주옥
Priority to KR1020160007542A priority Critical patent/KR20170087677A/en
Publication of KR20170087677A publication Critical patent/KR20170087677A/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022—Compressor control arrangements
    • F25B41/04—
    • F25B41/062—
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/006—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass for preventing frost
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/11—Fan speed control
    • F25B2600/111—Fan speed control of condenser fans
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/11—Fan speed control
    • F25B2600/112—Fan speed control of evaporator fans
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2513—Expansion valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/02—Humidity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2116—Temperatures of a condenser
    • F25B2700/21163—Temperatures of a condenser of the refrigerant at the outlet of the condenser
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2117—Temperatures of an evaporator
    • F25B2700/21171—Temperatures of an evaporator of the fluid cooled by the evaporator
    • F25B2700/21172—Temperatures of an evaporator of the fluid cooled by the evaporator at the inlet

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Abstract

The present invention relates to a refrigeration showcase control system that can maintain a refrigeration temperature and a refrigerating humidity uniformly by controlling each of a compressor, a condenser, an expansion valve, and an evaporator, .

Description

{CONTROL SYSTEM FOR REFRIGERATION SHOWCASE}

The present invention relates to a refrigeration showcase control system, and more particularly, to a refrigerated showcase control system that controls a compressor, a condenser, an expansion valve, and an evaporator, respectively, to maintain a refrigeration temperature and a refrigerating humidity uniformly, The present invention relates to a refrigerated showcase control system that can be extended.

Generally, as shown in Fig. 1, a refrigeration showcase is provided with a refrigerating compartment so that foods can be stored and stored for a long time freshly, and a control system (mainly, setting under the refrigerating compartment) for controlling the temperature of the refrigerating compartment, Such refrigerated showcase is installed in a supermarket, a large store, a shopping center, etc., so that when a consumer selects a product to be purchased while looking at the internal food, the manager can take out the food inside.

The refrigeration showcase control system according to the prior art includes a compressor, a condenser, an expansion valve

And a controller for controlling the compressor compares the temperature value of the temperature sensor provided in the refrigerating compartment with the set temperature value. When the temperature is equal to or higher than the set temperature, the controller drives the compressor and circulates the refrigerant generated by the evaporator, Is designed.

That is, when the temperature of the refrigerating compartment is equal to or higher than the set value, the compressor is driven, the refrigerant compressed by the compressor at high temperature and high pressure is condensed in the condenser, and the refrigerating compartment is kept at low temperature by the expansion valve and the evaporator.

However, according to the conventional refrigeration showcase control system having such a configuration, the refrigeration showcase control system is configured to simultaneously control the compressor, the condenser, the expansion valve, and the evaporator according to the difference between the temperature and the set temperature of the refrigerating chamber. And the like.

It is an object of the present invention to provide a refrigeration showcase control system which can maintain a refrigeration temperature and a refrigerating humidity uniformly by controlling each of a compressor, a condenser, an expansion valve and an evaporator, .

According to an aspect of the present invention, there is provided a refrigerator comprising: a compressor for compressing refrigerant at a high temperature and a high pressure; a condenser for condensing the refrigerant of high temperature and high pressure by the compressor into a liquid of middle temperature and high pressure by utilizing a condensing fan; And an evaporator for evaporating the spray of the low temperature and low pressure by the expansion valve to the low temperature and low pressure gas by using the evaporation fan to lower the refrigerating temperature of the refrigerating chamber, The refrigerator of claim 1, wherein the refrigerator compartment includes a first sensor that senses a refrigeration temperature of the refrigerating compartment, and a second sensor that senses a refrigerating temperature of the refrigerator compartment when the refrigerating temperature of the refrigerating compartment is within a dead- And a controller for starting the compressor after 30 seconds.

The present invention is characterized in that when the refrigeration temperature of the refrigerating compartment sensed by the first sensor is equal to a preset temperature (for example, 5 DEG C) to a dead band temperature (set temperature 5 DEG C + 2 DEG C = 7 DEG C) It is possible to improve the durability of the compressor while ensuring the stability of the piping for guiding the flow of the refrigerant by starting the compressor 10 to 30 seconds after.

The present invention is advantageous in that when the outlet temperature of the condenser sensed by the second sensor is lower than a set temperature (for example, 5 ° C), the controller can stop the condensing fan to ensure life and save energy have.

The present invention is effective in preventing the attachment and deposition of dust and foreign matter by preventing the controller from rotating forward and backward alternately in order to ensure the cleanliness and guarantee the life of the condensing fan itself have.

In the present invention, the inlet temperature of the evaporator by the third sensor is compared with the refrigerating temperature by the first sensor. If the difference is less than the comparison temperature (for example, 3 ° C), the evaporation fan is operated at a low speed to prevent unnecessary energy wastage The evaporation fan is operated at a high speed to make the refrigerator comply with the temperature of the refrigerating compartment when the difference between the inlet temperature of the evaporator by the third sensor and the refrigerating temperature by the first sensor is equal to or higher than the comparison temperature The temperature can be quickly lowered to the set temperature (for example, 5 DEG C).

The defrost fan is started only when the difference between the outside temperature of the refrigerating compartment by the fourth sensor and the refrigerating temperature by the first sensor is larger than the deviation temperature (for example, 15 ° C) So that it is possible to prevent the occurrence of frost at any time during the four seasons while minimizing waste of energy.

The controller compares the refrigerating humidity sensed by the humidity sensor with the set humidity (for example, 80%), and if the difference is 5% to 10% or more, the solenoid valve is immediately opened to direct the refrigerant of the compressor directly to the evaporator (For example, 80%) can be quickly adjusted.

The present invention relates to a system and method for controlling a controller by transmitting an alarm signal (abnormality of a refrigeration showcase control system) to a manager terminal through a wired or wireless communication network when an abnormality occurs in any one of a compressor, a condenser, an expansion valve, And the like.

The refrigerating showcase control system according to the present invention will now be described with reference to the drawings. There may be a plurality of refrigerating showcase control systems, and in particular, the refrigerating showcase control system may be applied to refrigerating showcase control systems. The scope of the claims is to be interpreted based on the understanding of the objects, features and advantages of the present invention.

The refrigeration showcase control system according to the present invention comprises a compressor for compressing a refrigerant at a high temperature and a high pressure, a condenser for condensing high-temperature and high-pressure refrigerant by a compressor into a medium-

Pressure evaporator for evaporating the low-temperature and low-pressure spray by the expansion valve to a low-temperature and low-pressure gas by using an evaporation fan, thereby controlling the refrigeration temperature of the refrigerator compartment The actual temperature of the evaporator.

At this time, the refrigeration showcase control system of the present invention comprises a first sensor for sensing the refrigeration temperature of the refrigerator compartment, and a dead band sensor for comparing the refrigeration temperature detected by the first sensor with a preset temperature (for example, ) In case of the temperature (set temperature 5 ℃ + 2 ℃ = 7 ℃), the controller includes the controller to start the compressor 10 to 30 seconds after operating the expansion valve.

The refrigerating showcase control system according to the related art has a compressor, an expansion valve and a condenser at the same time when the refrigerating temperature of the refrigerating compartment becomes a dead band temperature (set temperature 5 [deg.] C + 2 [ And is stopped when the temperature is increased to 5 占 폚.

However, in this structure, frequent operation of the compressor, the condenser and the expansion valve causes waste of energy, and in particular, excessive pressure is exerted on the pipe leading to the flow of the refrigerant due to the operation of the compressor when the expansion valve is closed At the same time, it causes a load on the compressor, which leads to unreasonable operation of the entire system and shortens the service life.

However, in the present invention, when the refrigerating temperature sensed by the first sensor is a dead band temperature (set temperature 5 [deg.] C + 2 [deg.] C = 30, the compressor is started 10 to 30 seconds later, thereby ensuring the stability of the piping for guiding the flow of the refrigerant, while ensuring the durability of the compressor.

Next, the refrigeration showcase control system according to the present invention includes a second sensor for sensing the outlet temperature of the condenser, and the controller is configured such that the outlet temperature of the condenser sensed by the second sensor is lower than a set temperature (for example, 5 ° C) The condensing fan 21 is stopped.

If the outlet temperature of the condenser is lower than the set temperature and the driving of the condensing fan is continued, the life of the condensing fan due to the long-time operation may be shortened, and further, energy is wasted. When the outlet temperature of the condenser detected by the sensor is lower than the set temperature (for example 5 ℃), it stops the condensing fan, thereby ensuring the lifetime as well as energy saving.

In addition, by allowing the controller to alternately rotate the forward and reverse rotation of the condensing fan, it is possible to prevent the attachment and deposition of dust and foreign matter due to forward and reverse rotation of the condensing fan, thereby ensuring cleanliness and ensuring the life of the condensing fan itself I will.

The refrigeration showcase control system according to the present invention includes a third sensor for sensing the inlet temperature of the evaporator, and the controller compares the inlet temperature of the evaporator by the third sensor with the refrigeration temperature by the first sensor, If the temperature is lower than the comparative temperature (for example, 3 ° C), the evaporation fan is operated at a low speed.

On the other hand, if the evaporation fan is driven at a high speed only, it may cause blistering inside the refrigerating chamber. Therefore, in the present invention, the inlet temperature of the evaporator by the third sensor is compared with the refrigerating temperature by the first sensor, (For example, 3 [deg.] C) or less, the evaporation fan is operated at a low speed to prevent unnecessary waste of energy, and at the same time to prevent the drying of the refrigerating compartment, and furthermore,

The evaporation fan is operated at a high speed so that the temperature of the refrigerating compartment can be quickly lowered to the set temperature (for example, 5 DEG C).

Meanwhile, the refrigeration showcase control system according to the present invention includes a defrost fan for removing the frost of the refrigerating compartment and a fourth sensor for sensing the outside temperature of the refrigerating compartment, and the controller controls the outdoor temperature of the refrigerating compartment by the fourth sensor, The defrost fan is started when the difference of the refrigerating temperature by the defrosting temperature is larger than the deviation temperature (for example, 15 ° C).

In the present invention, when the difference between the outside temperature of the refrigerating compartment and the refrigerating compartment of the refrigerator compartment is equal to or greater than 15 ° C, the outside temperature of the refrigerator compartment due to the fourth sensor, The defrost fan is started only when the temperature difference is greater than the deviation temperature (for example, 15 ° C), thereby minimizing energy waste and preventing the occurrence of frost at any time during the four seasons.

On the other hand, the refrigeration showcase control system according to the present invention includes a humidity sensor for sensing the refrigeration humidity (actual humidity of the refrigerator compartment) of the refrigerator compartment, and a solenoid valve for supplying the refrigerant compressed at a high temperature and high pressure by the compressor to the evaporator, The controller compares the refrigerated humidity detected by the humidity sensor with the set humidity (for example, 80%) and if the difference is more than 5% to 10%, the solenoid valve is opened and then closed.

When the evaporation fan is driven for a long time, the refrigerating chamber gradually dries. In order to quickly solve such a drying phenomenon, the controller compares the refrigerating humidity sensed by the humidity sensor with the set humidity (for example, 80% (For example, 80%) by rapidly opening the solenoid valve immediately to supply the refrigerant of the compressor directly to the evaporator (preferably, the solenoid valve

For 40 seconds to open and 10 seconds to close, and to close the compressor at the same time).

When an abnormality occurs in any one of the compressor, the condenser, the expansion valve, and the evaporator, the controller transmits an alarm signal (abnormality of the refrigerator showcase control system) to the manager terminal through a wired or wireless communication network to enable quick response do.

The operation of the refrigeration showcase control system according to the present invention having the above-described configuration will now be described.

First, the refrigerant in the compressor is compressed to a high temperature and a high pressure. In the condenser, the high-temperature and high-pressure refrigerant of the compressor is condensed into a medium-temperature high-pressure liquid by using a condensing fan. And the evaporator is used to evaporate low-temperature and low-pressure spray from the expansion valve by an evaporator to a low-temperature and low-pressure gas using an evaporation fan to lower the refrigeration temperature of the refrigerator compartment (the actual temperature of the refrigerator compartment).

At this time, when the refrigerating temperature detected by the first sensor for sensing the refrigerating temperature of the refrigerating chamber is the dead band temperature (set temperature 5 [deg.] C + 2 [deg.] C = 7 deg. C) The compressor 10 is started 10 to 30 seconds after the expansion valve is operated.

Then, the controller stops the condensing fan when the outlet temperature of the condenser sensed by the second sensor is lower than a set temperature (for example, 5 DEG C), and further the controller rotates the condensing fan alternately forward and reverse, To prevent adhesion and deposition of foreign matter.

The controller compares the inlet temperature of the evaporator by the third sensor with the refrigerating temperature by the first sensor. If the difference is less than or equal to a comparative temperature (for example, 3 DEG C), the controller operates the evaporator at a low speed. .

If the difference between the outside temperature of the refrigerator compartment by the fourth sensor and the refrigerator temperature by the first sensor is larger than the deviation temperature (for example, 15 DEG C), the controller starts the defrost fan to remove the frost.

In addition, the controller compares the refrigerated humidity sensed by the humidity sensor with the set humidity (eg, 80%) and when the difference is greater than 5% to 10%, the solenoid valve is opened and then closed.

On the other hand, when an abnormality occurs in any one of the compressor, the condenser, the expansion valve and the evaporator, the controller transmits the alarm signal (abnormality of the refrigerator showcase control system) to the manager terminal through the wired or wireless communication network, So that it can be processed quickly.

According to the configuration and operation, the humidity of the refrigerating chamber applied to the refrigeration showcase control system according to the present invention can be maintained at an average of 74.4% at a maximum of 82% and at the lowest 64%, and the temperature of the refrigerating chamber can be maximum 5.3 ° C and minimum 4.0 ° C An average of 4.6 ° C can be maintained.

Claims (7)

A condenser for condensing the high-temperature and high-pressure refrigerant by the compressor to a medium-temperature and high-pressure liquid by using the condensing fan; and a low-temperature and low-pressure sprayer for decompressing the medium- And an evaporator for evaporating the spray of low-temperature and low-pressure sprayed by the expansion valve to a low-temperature and low-pressure gas by utilizing an evaporation fan to lower a refrigerating temperature of the refrigerating chamber, the refrigerating showcase control system comprising: A first sensor for sensing a temperature of the refrigerating compartment; a first sensor for sensing a temperature of the refrigerating compartment;
And a controller for starting the compressor 10 to 30 seconds after the valve is operated. 2. The apparatus of claim 1, further comprising a second sensor for sensing an outlet temperature of the condenser,
Wherein the controller stops the condensing fan when the outlet temperature of the condenser sensed by the second sensor is lower than the set temperature. The refrigeration showcase control system according to claim 2, wherein the controller alternately rotates forward and reverse the condensing fan. 2. The evaporator according to claim 1, further comprising a third sensor for sensing an inlet temperature of the evaporator,
The controller compares the inlet temperature of the evaporator by the third sensor with the refrigerating temperature by the first sensor and operates the evaporation fan at a low speed when the difference is equal to or lower than the comparative temperature, Wherein the refrigerator is a refrigerator. The refrigerator of claim 1, further comprising: a defrost fan to remove frost from the refrigerating compartment; and a fourth sensor to sense an outside temperature of the refrigerating compartment, And the defrost fan is started when the difference of the refrigerating temperature by the sensor is larger than the deviation temperature.
Stem. The refrigerator according to claim 1, further comprising: a humidity sensor for sensing a refrigerating humidity of the refrigerating chamber; and a solenoid valve for supplying a refrigerant compressed at a high temperature and a high pressure to the evaporator by the compressor, Wherein the solenoid valve is opened and closed when the difference between the refrigerating humidity and the set humidity is 5 to 10% or more. The refrigerator according to any one of claims 1 to 6, wherein the controller transmits an alarm signal to an administrator terminal through a wired or wireless communication network when an abnormality occurs in any one of the compressor, the condenser, the expansion valve and the evaporator Wherein the refrigerator is a refrigerator.
KR1020160007542A 2016-01-21 2016-01-21 Control system for refrigeration showcase KR20170087677A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020160007542A KR20170087677A (en) 2016-01-21 2016-01-21 Control system for refrigeration showcase

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020160007542A KR20170087677A (en) 2016-01-21 2016-01-21 Control system for refrigeration showcase

Publications (1)

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KR20170087677A true KR20170087677A (en) 2017-07-31

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KR1020160007542A KR20170087677A (en) 2016-01-21 2016-01-21 Control system for refrigeration showcase

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113847748A (en) * 2021-08-16 2021-12-28 珠海格力电器股份有限公司 Multi-split system, control method thereof and storage medium

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113847748A (en) * 2021-08-16 2021-12-28 珠海格力电器股份有限公司 Multi-split system, control method thereof and storage medium

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