Refrigerating system, system operation control method and refrigerating equipment

Abstract

The invention relates to the technical field of refrigeration equipment, and provides a refrigeration system which comprises a compressor, the compressor is connected with a condenser, the condenser is connected with a first throttling element, and the first throttling element is connected with an inlet of a gas-liquid separator; a liquid phase outlet of the gas-liquid separator is connected with the evaporator; the compressor is a double-suction compressor, and two suction ends of the compressor are respectively connected with the evaporator and a gas phase outlet of the gas-liquid separator; and temperature sensors are respectively arranged at two outlets of the gas-liquid separator. Therefore, by detecting the temperatures of the refrigerants at the gas phase outlet and the liquid phase outlet of the gas-liquid separator in real time and comparing the relation between the temperature difference value of the two and the preset value, whether the refrigerating system can cope with the current working condition or not is judged, and meanwhile response is made in time. The state of the refrigerant supplied to the evaporator is monitored through temperature, and the rotating speed of the compressor is dynamically adjusted according to real-time data, so that the rotating speed is matched with the current working condition. The invention further provides a system operation control method and refrigeration equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of refrigeration equipment, and in particular relates to a refrigeration system, a system operation control method and refrigeration equipment. Background Art

[0002] Existing refrigerator refrigeration systems use single-suction compressors, which operate stably under normal operating conditions. However, under complex operating conditions such as large ambient temperature fluctuations and frequent load fluctuations, existing single-suction compressor systems are unable to detect and respond promptly, resulting in delayed response times, reduced energy efficiency, and decreased system stability.

[0003] In summary, the existing technology has obvious inconveniences and defects in actual use, so it is necessary to improve it. Summary of the Invention

[0004] In view of the above-mentioned defects, the present invention mainly provides a refrigeration system to solve the technical problem that the system cannot operate stably under complex working conditions.

[0005] In order to solve the above problems, the present invention provides a refrigeration system, comprising a compressor, the compressor being connected to a condenser, the condenser being connected to a first throttling member, the first throttling member being connected to an inlet of a gas-liquid separator; the liquid phase outlet of the gas-liquid separator being connected to an evaporator;

[0006] The compressor is a double-suction compressor, and its two suction ends are connected to the gas phase outlet of the evaporator and the gas-liquid separator respectively;

[0007] The gas phase outlet and liquid phase outlet of the gas-liquid separator are respectively provided with a gas phase temperature sensor and a liquid phase temperature sensor;

[0008] The gas phase temperature sensor is configured to detect the temperature of the refrigerant separated from the gas phase outlet of the gas-liquid separator, which is denoted as T a ;

[0009] The liquid phase temperature sensor is configured to detect the temperature of the refrigerant separated from the liquid phase outlet of the gas-liquid separator, which is denoted as T b .

[0010] According to the refrigeration system of the present invention, a second throttling member is connected between the liquid phase outlet of the gas-liquid separator and the inlet of the evaporator; an evaporation inlet temperature sensor is provided at the inlet of the evaporator;

[0011] The evaporation inlet temperature sensor is configured to detect the temperature of the refrigerant entering the evaporator, which is denoted as T c .

[0012] According to the refrigeration system of the present invention, a heat exchange connection is formed between the second throttling element and the return air pipeline of the compressor.

[0013] According to the refrigeration system of the present invention, the first throttling member is a first capillary tube, and the second throttling member is a second capillary tube.

[0014] A system operation control method based on the refrigeration system includes the following steps:

[0015] S1, detect the real-time temperature T of the refrigeration room 间 ;

[0016] S2, judge T 间 The target temperature T is set 阈 relationship; if T 间 ≥T 阈 , the compressor starts;

[0017] S3, set the preset values ​​Δ1, Δ2, Δ3 and Δ4; judge T a -T b Relationship with Δ1 and / or T a -T c Relationship with Δ3;

[0018] If T a -T b ≥Δ1 and / or T a -T c ≥Δ3, the compressor maintains the current speed;

[0019] If T a -T b <Δ1 and / or T a -T c <Δ3, the compressor speed increases;

[0020] S4, if step S3 determines T a -T b The relationship between T and Δ1 is as follows: a -T b The relationship between Δ2 and Δ2 is that Δ2>Δ1; specifically:

[0021] If T a -T b ≥Δ2, the compressor 1 reduces its speed;

[0022] If Δ1≤T a -T b <Δ2, the compressor 1 maintains the current speed;

[0023] If step S3 determines that T a -T c The relationship between T and Δ3 is as follows:a -T c The relationship between Δ3 and Δ4 is ​​that Δ3>Δ4; specifically:

[0024] If T a -T c ≥Δ4, the compressor reduces the speed;

[0025] If Δ3≤T a -T c <Δ4, the compressor maintains the current speed;

[0026] S5, repeat steps S2 and S3, and detect the real-time temperature T of the refrigeration compartment 间 ;

[0027] Judge T 间 -T 阈 Δ to the preset shutdown value 关 relationship;

[0028] If T 间 -T 阈 ≤Δ 关 , the compressor turns off.

[0029] According to the system operation control method of the present invention, when the step S5 is executed, S2, S3, T 间 Detection and T 间 -T 阈 With Δ 关 Judgment of relationship.

[0030] According to the system operation control method of the present invention, the ranges of Δ1, Δ2, Δ3, and Δ4 are respectively:

[0031] Δ1: 2-10; Δ2: 6-20;

[0032] Δ3:3-12; Δ4:8-22.

[0033] According to the system operation control method of the present invention, the Δ 关 The range is: -5 to -1.

[0034] A refrigeration device has the refrigeration system and / or can execute the system operation control method.

[0035] The refrigeration equipment according to the present invention is a refrigerator, a freezer, a cold chain device or a cold storage.

[0036] In summary, the refrigeration system of the present invention detects the temperature of the refrigerant at the gas phase outlet and the liquid phase outlet of the gas-liquid separator in real time, and by comparing the temperature difference between the two with the preset value, determines whether the refrigeration system can cope with the current working conditions and responds in a timely manner. The refrigeration system can cope with complex working conditions, has strong adaptability and high stability. The present invention monitors the state of the refrigerant supplied to the evaporator through temperature monitoring, and dynamically adjusts the compressor speed according to real-time data to match the current working conditions. The refrigeration system has a higher energy efficiency ratio and better deep cooling performance. The present invention also provides a system operation control method and refrigeration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of the refrigeration system of the present invention;

[0038] In the figure: 1- compressor, 11- condenser, 12- gas-liquid separator, 13- evaporator, 14- first capillary tube, 15- second capillary tube; 2- gas phase temperature sensor, 21- liquid phase temperature sensor, 22- evaporation inlet temperature sensor. DETAILED DESCRIPTION

[0039] See also Figure 1 The present invention provides a refrigeration system, comprising a compressor 1, wherein the compressor 1 is connected to a condenser 11, wherein the condenser 11 is connected to a first throttling member, wherein the first throttling member is connected to an inlet of a gas-liquid separator 12; and wherein a liquid phase outlet of the gas-liquid separator 12 is connected to an evaporator 13;

[0040] The compressor 1 is a double-suction compressor, and its two suction ends are connected to the gas phase outlet of the evaporator 13 and the gas-liquid separator 12 respectively;

[0041] The gas phase outlet and liquid phase outlet of the gas-liquid separator 12 are respectively provided with a gas phase temperature sensor 2 and a liquid phase temperature sensor 21;

[0042] The temperature of the refrigerant separated from the gas-liquid separator 12 is detected by the gas phase temperature sensor 2 as T a The temperature of the refrigerant separated from the gas-liquid separator 12 is detected by the liquid phase temperature sensor 21 as T b ;

[0043] The temperature of the gaseous refrigerant is high, and the temperature of the liquid refrigerant is low. a 、T b It can indicate the content of liquid refrigerant in the pipeline. a -T b The size of the difference can be used to qualitatively determine the content of liquid refrigerant in the liquid phase outlet pipeline.

[0044] In order to accurately judge whether the amount of liquid refrigerant supplied to the evaporator 13 in the refrigeration system can cope with the actual operating conditions, the inventors conducted multiple tests and verified that the critical point value at which the refrigeration system cannot cope with the current operating conditions is selected as the preset value Δ1, and by comparing T a -T b The relationship between the difference and the preset value Δ1 is used to judge whether the current operating parameters of the refrigeration system can cope with the existing working conditions and respond in time.

[0045] If T a -T b ≥Δ1, indicating that the amount of liquid refrigerant in the system can cope with the current working conditions, and compressor 1 maintains the current speed;

[0046] If T a -T b <Δ1, indicating that the amount of liquid refrigerant in the system is insufficient. Compressor 1 increases its speed to speed up the circulation of refrigerant in the system and increase the supply of liquid refrigerant to cope with the current working conditions.

[0047] The present invention detects the refrigerant temperature at the gas and liquid outlets of the gas-liquid separator 12 in real time and compares the temperature difference between the two with a preset value to determine whether the refrigeration system can cope with the current operating conditions and respond promptly. The refrigeration system can cope with complex operating conditions, has strong adaptability, and is highly stable.

[0048] When the working condition changes, the system responds and runs for a period of time before reaching a new stable state. Furthermore, in order to avoid excessive system response and affecting the operation of the new stable state, the inventors also selected a preset value Δ2 for the refrigeration system to establish and maintain the new stable state, Δ2>Δ1. And by comparing T a -T b The relationship between the difference and the preset value Δ2 is used to judge the operating status of the system and make corresponding responses. Specifically:

[0049] If T a -T b ≥Δ2, indicating that the amount of liquid refrigerant in the system is oversupplied, and compressor 1 reduces its speed;

[0050] If Δ1≤T a -T b <Δ2, indicating that the amount of liquid refrigerant in the system is sufficient to maintain stable operation of the system and compressor 1 maintains the current speed;

[0051] The aforementioned embodiment is applicable to cold chain equipment with a large refrigerant charge.

[0052] For household refrigerators, in order to ensure the refrigeration capacity and system stability, as an embodiment, a second throttling member is connected between the liquid phase outlet of the gas-liquid separator 12 and the inlet of the evaporator 13; an evaporation inlet temperature sensor 22 is provided at the inlet of the evaporator 13;

[0053] After the refrigerant passes through the second throttle, the pressure decreases; the temperature T of the refrigerant entering the evaporator 13 is detected by the evaporation inlet temperature sensor 22. c ; It can directly represent the refrigeration capacity of the evaporator 13. a -T c The size of the difference can be used to qualitatively determine the amount of liquid refrigerant supplied to the evaporator 13.

[0054] As an implementation mode, the inventors also set Δ3 and Δ4, and Δ3<Δ4.

[0055] By comparing T a -T c The relationship between the difference and the preset value Δ3 is used to judge whether the current operating parameters of the refrigeration system can cope with the existing working conditions and respond in time.

[0056] If T a -T c ≥Δ3, indicating that the amount of liquid refrigerant in the system can cope with the current working conditions, and compressor 1 maintains the current speed;

[0057] If T a -T c <Δ3, indicating that the amount of liquid refrigerant in the system is insufficient. Compressor 1 increases its speed to speed up the circulation of refrigerant in the system and increase the supply of liquid refrigerant to cope with the current working conditions.

[0058] By comparing T a -T c The relationship between the difference and the preset value Δ4 is ​​used to judge the operating status of the system and make corresponding responses.

[0059] Specifically:

[0060] If T a -T c ≥Δ4, indicating that the amount of liquid refrigerant in the system is oversupplied, and compressor 1 reduces its speed;

[0061] If Δ3≤T a -T c <Δ4, indicating that the amount of liquid refrigerant in the system is sufficient to maintain stable operation of the system and compressor 1 maintains the current speed;

[0062] Δ1, Δ2, Δ3, and Δ4 of the present invention can be adaptively set according to factors such as the type of the evaporator 13 and the refrigeration equipment.

[0063] As an embodiment, a heat exchange connection is formed between the second throttling member and the return air pipeline of the compressor 1, which further promotes the vaporization of the refrigerant in the return air pipeline, and at the same time promotes the liquefaction of the refrigerant flowing through the second throttling member, thereby increasing the amount of liquid refrigerant entering the evaporator 13, improving the refrigeration capacity, and achieving lower temperature refrigeration.

[0064] Furthermore, the first throttling member is a first capillary tube 14 , and the second throttling member is a second capillary tube 15 .

[0065] As an embodiment, the refrigeration system of the present invention has a control unit for setting preset values, receiving detected temperature values, performing parameter calculations and comparisons, and outputting corresponding control signals for the compressor 13 .

[0066] The present invention detects the refrigerant temperature at the gas and liquid outlets of the gas-liquid separator 12 in real time and compares the temperature difference between the two with a preset value to determine whether the refrigeration system can cope with the current operating conditions and respond promptly. The refrigeration system is capable of handling complex operating conditions, exhibits strong adaptability, and exhibits high stability. The present invention monitors the state of the refrigerant supplied to the evaporator 13 through temperature monitoring and dynamically adjusts the compressor speed based on real-time data to match the current operating conditions. This results in a refrigeration system with higher energy efficiency and improved cryogenic performance.

[0067] The present invention also provides a system operation control method based on the refrigeration system, comprising the following steps:

[0068] S1, detect the real-time temperature T of the refrigeration room 间 ;

[0069] S2, judge T 间 The target temperature T is set 阈 relationship; if T 间 ≥T 阈 , then compressor 1 starts;

[0070] Optionally, the threshold temperature can be set according to different products, such as -40 to -10°C or 4 to 15°C.

[0071] S3, judge T a -T b Relationship with Δ1 and / or T a -T c Relationship with Δ3;

[0072] If T a -T b ≥Δ1 and / or Ta -T c ≥Δ3, the compressor 1 maintains the current speed;

[0073] If T a -T b <Δ1 and / or T a -T c <Δ3, the speed of compressor 1 increases;

[0074] Those skilled in the art can select the judgment conditions according to factors such as the volume of the refrigeration compartment, the specifications of the evaporator 13 and the application scenario of the refrigeration equipment, such as only judging T a -T b Relationship with Δ1 or T a -T c The relationship with Δ3; it is also possible to judge both at the same time.

[0075] S4, if step S3 determines T a -T b The relationship between T and Δ1 is as follows: a -T b The relationship between Δ2 and Δ2 is that Δ2>Δ1; specifically:

[0076] If T a -T b ≥Δ2, the compressor 1 reduces its speed;

[0077] If Δ1≤T a -T b <Δ2, the compressor 1 maintains the current speed;

[0078] If step S3 determines that T a -T c The relationship between T and Δ3 is as follows: a -T c The relationship between Δ3 and Δ4 is ​​that Δ3>Δ4; specifically:

[0079] If T a -T c ≥Δ4, the compressor 1 reduces its speed;

[0080] If Δ3≤T a -T c <Δ4, the compressor 1 maintains the current speed;

[0081] The speed and speed adjustment method of the compressor 1 can be completed by selecting the control strategy of the existing known refrigeration system. S5, repeat the steps S2 and S3, and detect the real-time temperature T of the refrigeration compartment. 间 , and judge T 间 -T 阈 Δ to the preset shutdown value 关relationship;

[0082] If T 间 -T 阈 ≤Δ 关 , then compressor 1 is turned off;

[0083] Optionally, when the step S5 is executed, S2, S3, and T 间 Detection and T 间 -T 阈 With Δ 关 The judgment of the relationship; it is also possible to execute T sequentially while executing S2 and S3 steps sequentially. 间 Detection and Δ 关 Those skilled in the art can make adaptive settings based on the actual functions of the refrigeration system.

[0084] The selection can be made adaptively based on the actual working conditions of the refrigeration equipment and in combination with known parameters. 关 The range is -5 to -1;

[0085] The refrigeration system then repeatedly executes steps S1-S5, detecting various operating parameters in real time and enabling the system to respond promptly.

[0086] As an embodiment, the ranges of Δ1, Δ2, Δ3, and Δ4 of the present invention are respectively:

[0087] Δ1: 2-10; Δ2: 6-20;

[0088] Δ3: 3-12; Δ4: 8-22;

[0089] The inventors selected different models of evaporators 13, refrigeration equipment and different operating conditions, and obtained the value combinations of Δ1 and Δ2, Δ3 and Δ4 through a large number of experiments, as shown in Table 1.

[0090] Table 1: Combinations of Δ1, Δ2, Δ3, and Δ4 values

[0091] Combination 1 Combination 2 Combination 3 Combination 4 Combination 5 Combination 6 Combination 7 <![CDATA[Δ1]]> 2 5 10 7 8 4 3 <![CDATA[Δ2]]> 4 7 20 11 13 6 5 <![CDATA[Δ3]]> 3 7 12 9 11 5 4 <![CDATA[Δ4]]> 8 12 22 15 17 10 9

[0092] The system operation control method of the present invention detects system operating parameters in real time, compares the relationships between the parameters, and transmits the comparison results to the control unit in real time. This enables the refrigeration system to promptly perceive and respond to changes in operating conditions, ensuring the stability of system operation.

[0093] The present invention also provides a refrigeration device having the above refrigeration system and / or capable of executing the above system operation control method;

[0094] The refrigeration equipment of the present invention can be a household appliance, such as a refrigerator or a freezer, or can be a work refrigeration equipment, such as a cold chain equipment, a cold storage, etc.

[0095] In summary, the present invention provides a refrigeration system that detects the temperature of the refrigerant at the gas phase outlet and the liquid phase outlet of the gas-liquid separator in real time, and by comparing the temperature difference between the two with the preset value, determines whether the refrigeration system can cope with the current working conditions and responds in a timely manner. The refrigeration system can cope with complex working conditions, has strong adaptability and high stability. The present invention monitors the state of the refrigerant supplied to the evaporator through temperature monitoring, and dynamically adjusts the compressor speed according to real-time data to match the current working conditions. The refrigeration system has a higher energy efficiency ratio and better deep cooling performance. The present invention also provides a system operation control method and refrigeration equipment.

[0096] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A refrigeration system, characterized in that: The compressor is connected to a condenser, the condenser is connected to a first throttling member, the first throttling member is connected to an inlet of a gas-liquid separator; the liquid phase outlet of the gas-liquid separator is connected to an evaporator; The compressor is a double-suction compressor, and its two suction ends are connected to the gas phase outlet of the evaporator and the gas-liquid separator respectively; The gas phase outlet and liquid phase outlet of the gas-liquid separator are respectively provided with a gas phase temperature sensor and a liquid phase temperature sensor; The gas phase temperature sensor is configured to detect the temperature of the refrigerant separated from the gas phase outlet of the gas-liquid separator, which is denoted as T a ; The liquid phase temperature sensor is configured to detect the temperature of the refrigerant separated from the liquid phase outlet of the gas-liquid separator, which is denoted as T b .

2. The refrigeration system according to claim 1, wherein: A second throttling member is connected between the liquid phase outlet of the gas-liquid separator and the inlet of the evaporator; an evaporation inlet temperature sensor is provided at the inlet of the evaporator; The evaporation inlet temperature sensor is configured to detect the temperature of the refrigerant entering the evaporator, which is denoted as T c .

3. The refrigeration system according to claim 2, wherein: A heat exchange connection is formed between the second throttling element and the return air pipeline of the compressor.

4. The refrigeration system according to claim 2, wherein: The first throttling member is a first capillary tube, and the second throttling member is a second capillary tube.

5. A system operation control method based on the refrigeration system according to any one of claims 2 to 4, characterized in that: The steps include: S1, detect the real-time temperature T of the refrigeration room 间 ; S2, judge T 间 The target temperature T is set 阈 relationship; if T 间 ≥T 阈 , the compressor starts; S3, set the preset values ​​Δ1, Δ2, Δ3 and Δ4; judge T a -T b Relationship with Δ1 and / or T a -T c Relationship with Δ3; If T a -T b ≥Δ1 and / or T a -T c ≥Δ3, the compressor maintains the current speed; If T a -T b <Δ1 and / or T a -T c <Δ3, the compressor speed increases; S4, if step S3 determines T a -T b The relationship between T and Δ1 is as follows: a -T b The relationship between Δ2 and Δ2 is that Δ2>Δ1; specifically: If T a -T b ≥Δ2, the compressor 1 reduces its speed; If Δ1≤T a -T b <Δ2, the compressor 1 maintains the current speed; If step S3 determines that T a -T c The relationship between T and Δ3 is as follows: a -T c The relationship between Δ3 and Δ4 is ​​that Δ3>Δ4; specifically: If T a -T c ≥Δ4, the compressor reduces the speed; If Δ3≤T a -T c <Δ4, the compressor maintains the current speed; S5, repeat steps S2 and S3, and detect the real-time temperature T of the refrigeration compartment 间 ; Judge T 间 -T 阈 Δ to the preset shutdown value 关 relationship; If T 间 -T 阈 ≤Δ 关 , the compressor turns off.

6. The system operation control method according to claim 5, characterized in that: When the step S5 is executed, S2, S3, T 间 Detection and T 间 -T 阈 With Δ 关 Judgment of relationship.

7. The system operation control method according to claim 5, characterized in that: The ranges of Δ1, Δ2, Δ3, and Δ4 are respectively: Δ1: 2-10; Δ2: 6-20; Δ3:3-12; Δ4:8-22.

8. The system operation control method according to claim 5, characterized in that: The Δ 关 The range is: -5 to -1.

9. A refrigeration device, characterized in that: A refrigeration system according to any one of claims 2 to 4 and / or a system operation control method according to any one of claims 6 to 8 can be executed.

10. The refrigeration equipment according to claim 9, characterized in that The refrigeration equipment is a refrigerator, a freezer, a cold chain equipment or a cold storage.

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