Energy-saving quick-freezing cold storage and its control method

Abstract

The present invention discloses an energy-saving quick-freezing cold storage and its control method, which relates to the field of cold storage, and includes a refrigeration machine room, a No. 1 freezer, and a No. 2 freezer. The No. 1 freezer and the No. 2 freezer are independently arranged, and the refrigeration machine room is respectively connected to the No. 1 freezer and the No. 2 freezer for refrigeration control; the pipeline is reasonably arranged with a clear layout, and the start and stop of the fluorine ceiling-mounted air cooler are controlled by combining multiple parameters. The refrigeration compressors are unloaded one by one until they stop, reducing energy consumption and saving operation costs.

Description

Technical Field

[0001] The present invention relates to the field of cold storage, and particularly to an energy-saving quick-freezing cold storage and its control method. Background Art

[0002] In the current cold storage refrigeration system, an intelligent controller is generally used to achieve automatic control of the cold storage by setting the target value of the cold storage temperature. However, using the cold storage temperature as the only refrigeration parameter to control the start and stop of the cold storage end fans can meet the refrigeration requirements of the storage, but it consumes electric energy and increases the operating cost. Summary of the Invention

[0003] To solve the deficiencies in the prior art, the present invention provides an energy-saving quick-freezing cold storage and its control method, with reasonable pipeline settings, clear layout, multi-parameter combined control of the start and stop of the fluorine ceiling-mounted cooling fans, and the refrigeration compressors are unloaded one by one until they stop, reducing energy consumption and saving the operating cost.

[0004] The technical solution adopted by the present invention to solve its technical problems is: an energy-saving quick-freezing cold storage, characterized in that it includes a refrigeration machine room, a No. 1 freezer, and a No. 2 freezer. The No. 1 freezer and the No. 2 freezer are independently arranged, and the refrigeration machine room is respectively connected to the No. 1 freezer and the No. 2 freezer for refrigeration control;

[0005] The refrigeration machine room: includes a connected refrigeration compressor unit and an evaporative condenser;

[0006] The No. 1 freezer: includes multiple fluorine ceiling-mounted cooling fans, and the multiple fluorine ceiling-mounted cooling fans are respectively connected to the refrigeration compressor unit and the evaporative condenser through pipelines;

[0007] The No. 2 freezer: includes multiple fluorine ceiling-mounted cooling fans, and the multiple fluorine ceiling-mounted cooling fans are respectively connected to the refrigeration compressor unit and the evaporative condenser through pipelines.

[0008] Further, the refrigeration compressor unit is a fluorine three-head parallel screw unit, including: a gas-liquid separator, a head, an economizer built in the unit, an oil separator, an oil cooling siphon tank, and a liquid receiver. The gas-liquid separator is connected to the head, the head is respectively connected to the economizer built in the unit and the oil separator, the oil separator is connected to the oil cooling siphon tank, the economizer built in the unit is connected to the liquid receiver, and the oil cooling siphon tank is communicated with the liquid receiver.

[0009] Further, the oil separator is connected to the evaporative condenser through a pipeline, and the oil cooling siphon tank is communicated to the pipeline between the oil separator and the evaporative condenser through a pipeline.

[0010] Further, one side of the evaporative condenser is respectively connected to the oil cooling siphon tank and the liquid receiver through pipelines.

[0011] Furthermore, the gas-liquid separator is connected to each fluorine ceiling air cooler of No. 1 freezer and No. 2 freezer through pipelines; each fluorine ceiling air cooler of No. 1 freezer and No. 2 freezer is connected to the connecting pipe between the oil separator and the evaporative condenser through pipelines; the unit's built-in economizer is connected to each fluorine ceiling air cooler of No. 1 freezer and No. 2 freezer through pipelines; each fluorine ceiling air cooler of No. 1 freezer and No. 2 freezer is connected to the connecting pipe between the evaporative condenser and the oil cooling siphon tank and the liquid storage tank through pipelines.

[0012] Furthermore, a fluorine-adding pipeline is connected to the pipeline between the economizer of the unit and the fluorine ceiling-type air coolers of the 1# freezer and the 2# freezer, and a fluorine-adding port is opened at one end of the fluorine-adding pipeline.

[0013] Furthermore, a temperature sensor is installed at the return air below the fluorine ceiling air cooler; each fluorine ceiling air cooler is provided with a thermal relay for overcurrent protection, and the setting value of the thermal relay is 0.95.-1.03 times the rated current; each fluorine ceiling air cooler is provided with a thermistor for motor thermal protection on the motor, and the thermistor is connected in series to the control circuit of the fluorine ceiling air cooler.

[0014] A method for controlling an energy-saving quick-freezing cold storage is used to control the energy-saving quick-freezing cold storage, and defines: TN: temperature; FN: number of running fans; T real-time: real-time temperature; T setting: set temperature; MINnjs: minimum energy level set point;

[0015] S1: Read the temperature of 1# freezer and 2# freezer T1...TN;

[0016] S2: Determine the temperature change trend of 1# freezer and 2# freezer;

[0017] S3: Read Treal-time and Tsetting and compare them;

[0018] S4: According to the temperature changes of 1# freezer and 2# freezer, when the set lower limit temperature is reached gradually, the refrigeration compressors are unloaded one by one and a shutdown signal is output;

[0019] S5: When only one refrigeration compressor is deloaded to less than MINnjs, determine whether there is a freezer with a rising temperature trend;

[0020] S6: When the refrigeration quantity of the fluorine ceiling type cold air machine in the freezer is less than the FN setting, the energy-saving control algorithm subroutine is called to output the corresponding control;

[0021] S7: Record the energy level change trend of each refrigeration compressor to ensure that the energy level of the refrigeration compressor operates at the point of maximum efficiency, and adjust one of the refrigeration compressors.

[0022] The beneficial effects of the present invention include: reasonable piping arrangement and clear layout; the fluorine ceiling air cooler is provided with a thermal relay to realize overcurrent protection; the motor of the fluorine ceiling air cooler is provided with a thermistor protection element to realize motor thermal protection; multiple parameters are combined to control the start and stop of the fluorine ceiling air cooler, and the refrigeration compressors are unloaded one by one until they are shut down, thereby reducing energy consumption and saving operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of the refrigeration room of the present invention;

[0024] Figure 2 This is a schematic diagram of the structure of the 1# freezer of the present invention;

[0025] Figure 3 This is a schematic diagram of the structure of the 2# freezer of the present invention.

[0026] Figure 4 This is the multi-controller communication wiring diagram of the present invention.

[0027] Reference numerals in the figure: 1, refrigeration compressor unit, 2, evaporative condenser, 3, fluorine ceiling air cooler, 4, fluorine adding pipeline;

[0028] 1.1. Gas-liquid separator, 1.2. Machine head, 1.3. Economizer built into the unit, 1.4. Oil separator, 1.5. Oil cooling siphon tank, 1.6. Liquid storage tank. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] An energy-saving quick-freezing cold storage, comprising a refrigeration room, a 1# freezer, and a 2# freezer, wherein the 1# freezer and the 2# freezer are independently arranged, and the refrigeration room is respectively connected to the 1# freezer and the 2# freezer for refrigeration control;

[0032] The refrigeration room: comprises a refrigeration compressor unit 1 and an evaporative condenser 2 connected to each other, both of which receive controller instructions to perform corresponding actions; preferably, two refrigeration compressor units 1 are provided, and two evaporative condensers 2 are provided; the refrigeration compressor unit 1 is preferably a fluorine three-head parallel screw unit;

[0033] The 1# freezer: comprises a plurality of fluorine ceiling-mounted air coolers 3, which are respectively connected to the refrigeration compressor unit 1 and the evaporative condenser 2 through pipelines;

[0034] The 2# freezer comprises a plurality of fluorine ceiling-mounted air coolers 3, which are respectively connected to the refrigeration compressor unit 1 and the evaporative condenser 2 through pipelines.

[0035] Preferably, the evaporative condenser 2 model is MKS-1285; the fluorine ceiling air cooler 3 model is LLK.p1337. The fluorine ceiling air cooler 3 is R507 direct expansion liquid supply, evaporation condensation temperature is -33 / +36℃, working medium defrost, double-layer insulation water tray, fan with electric heating wire 4*0.72KW / unit, fan 4*3.0KW / unit.

[0036] The fluorine three-head parallel screw unit comprises: a gas-liquid separator 1.1, a head 1.2, an economizer 1.3 of the unit, an oil separator 1.4, an oil cooling siphon tank 1.5, and a liquid storage tank 1.6. The gas-liquid separator 1.1 is connected to the head 1.2, the head 1.2 is respectively connected to the economizer 1.3 and the oil separator 1.4 of the unit, the oil separator 1.4 is connected to the oil cooling siphon tank 1.5, the economizer 1.3 of the unit is connected to the liquid storage tank 1.6, and the oil cooling siphon tank 1.5 is connected to the liquid storage tank 1.6. Preferably, the head 1.2 model is: 3×HSN8571-125-40P, and a temperature sensor is installed at the return air below the fluorine ceiling air cooler 3; each fluorine ceiling air cooler 3 is provided with a thermal relay for overcurrent protection, and the setting value of the thermal relay is 095.-1.03 times the rated current; each fluorine ceiling air cooler 3 is provided with a thermistor protection element for motor thermal protection on the motor, and the thermistor protection element is connected in series to the control circuit of the fluorine ceiling air cooler 3.

[0037] The oil separator 1.4 is connected to the evaporative condenser 2 through a pipeline, and the oil cooling siphon tank 1.5 is connected to the connecting pipeline between the oil separator 1.4 and the evaporative condenser 2 through a pipeline. One side of the evaporative condenser 2 is connected to the oil cooling siphon tank 1.5 and the liquid storage tank 1.6 through pipelines.

[0038] The gas-liquid separator 1.1 is connected to each fluorine ceiling air cooler 3 of the 1# freezer and the 2# freezer through pipelines; each fluorine ceiling air cooler 3 of the 1# freezer and the 2# freezer is connected to the connecting pipe between the oil separator 1.4 and the evaporative condenser 2 through pipelines; the unit's built-in economizer 1.3 is connected to each fluorine ceiling air cooler 3 of the 1# freezer and the 2# freezer through pipelines; each fluorine ceiling air cooler 3 of the 1# freezer and the 2# freezer is connected to the connecting pipe between the evaporative condenser 2 and the oil cooling siphon tank 1.5 and the liquid storage tank 1.6 through pipelines.

[0039] A fluorine-adding pipeline 4 is connected to the pipeline between the self-contained economizer 1.3 of the unit and the fluorine ceiling-type air coolers 3 of the 1# freezer and the 2# freezer, and a fluorine-adding port is opened at one end of the fluorine-adding pipeline 4.

[0040] Example 2

[0041] The refrigeration compressor in the quick-freezing cold storage system is the device that consumes the most electricity. The operating efficiency of the refrigeration compressor is the key monitoring object. This embodiment provides a parameter energy efficiency ratio COP value calculation formula for whether the refrigeration compressor is operating economically:

[0042] COP=Q / P=1.16*L(T2-T1)

[0043] Where: Q: refrigeration capacity of refrigeration compressor (kW); P: operating power of refrigeration compressor (kW), L: flow rate (m3 / h); T2: inlet temperature (℃); T1: outlet temperature (℃). It can be seen from the formula that making the operating power smaller and the refrigeration capacity larger can improve the COP value of the refrigeration compressor. 1.16 is a data constant obtained from engineering practice. In actual operation, it is found that the COP value is the highest when the energy level is close to 100%. This embodiment gives the formula for calculating the comprehensive energy consumption:

[0044]

[0045] Where: F: total power consumption; n: number of power-consuming devices; ei: power consumption of the ith device; pi: conversion coefficient of the ith device (here mainly considering the energy level of the refrigeration compressor); h: equipment operation time (hours).

[0046] In order to optimize the COP value and F value, the mathematical programming method, that is, the energy-saving control algorithm strategy, is adopted. The steps are as follows:

[0047] A method for controlling an energy-saving quick-freezing cold storage is used to control the energy-saving quick-freezing cold storage described in Example 1, and defines: T: cold storage temperature; F N : Number of running fans; T 实时 : Real-time temperature; T 设定 : Set temperature; MIN njs : minimum energy level set point;

[0048] S1: Read the temperature of 1# freezer and 2# freezer T1...T N ; 1-N represent different times, T1...T N Indicates the cold storage temperature at different times;

[0049] S2: Determine the temperature change trend of 1# freezer and 2# freezer;

[0050] S3: Read T 实时 With T设定 And compare the two; divide the automatic temperature reduction program of the refrigeration compressor into two processes: ① rapid temperature reduction process; ② steady-state temperature reduction process. In these two temperature reduction processes, the target temperature of the steady-state temperature reduction is set as T by the host computer 设定1 , and the target temperature of the rapid temperature reduction is set as T by the host computer 设定2 . The average outlet air temperature is obtained as T by measuring the cold storage value in real time through the temperature sensor 平均 ; the difference between the target temperature of the steady-state temperature reduction and the target temperature of the rapid temperature reduction is set as T3 (T 设定2 = T 设定1 + T3) by the host computer; before performing the rapid temperature reduction action, manually input T 设定1 , T3. When T 平均 = T 设定2 , after a delay, automatically switch to the steady-state temperature reduction process, input the refrigeration parameters required for the steady-state temperature reduction into the controllers of each refrigeration equipment, and finally achieve the stable control of T 平均 = T 设定1 .

[0051] S4: According to the temperature changes of the No. 1 cold storage and the No. 2 cold storage, let T be the temperature of the cold storage, K be the change ratio, T0 be the starting temperature, and t be the time. Regarding the temperature change process as an infinite number of straight-line segments, in the stage of T = Kt + T0 (Kt is a constant representing the change ratio at time t), when T reaches the set temperature range, it starts to change slowly and gradually reaches the set lower limit temperature. Calculate the K value at any time. When the temperature change trend approaches T 设定1 , unload the refrigeration compressor one by one and output the unloading signal.

[0052] S5: Adopt the trend approximation method. When only one refrigeration compressor is unloaded to less than MIN njs , determine whether there is a cold storage with a temperature trend rising;

[0053] S6: When the refrigeration quantity of the fluorine ceiling-mounted air cooler 3 in the cold storage is less than the set value of F N , call the energy-saving control algorithm subroutine SUB and output the corresponding control strategy; the steps of the subroutine SUB are as follows:

[0054] Ss1: Set the increase and decrease range of the control set value of the refrigeration compressor;

[0055] Ss2: Set the upper and lower limits of the temperature for the cold storage to meet the floating of the control set value of the refrigeration compressor;

[0056] Ss3: Regularly detect the temperature of the cold storage, accumulate the number of times the cold storage temperature is lower than the lower limit and higher than the upper limit. When the set number percentage limit is reached, adjust the number of the first and second heads of the refrigeration compressor running;

[0057] Ss4: Through data accumulation, use a convolutional neural network to analyze big data and output a self-learning and adaptive dynamic control strategy.

[0058] ② The convolutional neural network is divided into an input layer, a convolutional layer, and an output layer.

[0059] ② Use the temperature data T collected at different time points as input data, and establish an analysis model for n Ts. Perform data preprocessing on the n Ts, clean, integrate, and assign values to interference and fault data, screen out the factors that have the greatest impact on the results, establish the dimension for screening target features, and thus automatically select control factors to determine whether it is the intermediate temperature of the cold storage body or the return air temperature and average outlet air temperature of the fluorine ceiling-mounted air cooler 3 as T 平均 As the control point.

[0060] ③ The analysis model outputs multiple prediction results corresponding to different outputs.

[0061] ④ Provide feedback on the prediction results to form a closed-loop control and continuously adjust the self-learning process.

[0062] ⑤ The self-learning process relies on the accumulation of data such as the temperature of the cold storage warehouse and the operating status of equipment, analyzes the data, compares the data, and thus adjusts the control strategy and outputs the control strategy for the refrigeration compressor.

[0063] ⑥ Define the warehouse temperature Ti of the cold storage, the required temperature Tj, and the incoming temperature Tz of the stored items. Ti and Tz are the main factors affecting the stability of Tj. In this embodiment, the influence of factors such as the opening and closing of the warehouse door, lighting heat generation, and warehouse body insulation is ignored here. Consider ΔT1 = Tz - Tj as the main parameter. Define 4 changes of ΔT1, namely ZB (positive large), ZM (positive medium), ZS (positive small), and ZE (zero) to represent the refrigeration state. And use ΔT2 = Ti - Tj as real-time fine-tuning. ΔT2 is also defined with the same 4 states as ΔT1. As long as it is not in the ZE area, the refrigeration compressor does not stop. According to the above settings, corresponding to adjusting 16 situations of the output change of the refrigeration compressor, the control rules are as follows in the table:

[0064] ΔT1

[0065]

[0066] ⑦ When the load is large, the adjustment time is long; when the load is small, the adjustment time is short.

[0067] The control of the refrigeration compressor uses a convolutional neural network to generate the best control rules, then makes decisions on the control rules, and then outputs them to the control unit. After optimization processing, it performs real-time temperature adjustment.

[0068] This function block can be set to two control modes: enabled and disabled.

[0069] Since there are multiple cold storage temperatures in the cold storage of the same system, when increasing or decreasing the number of the heads 1.2 of the refrigeration compressor in operation, the temperatures of multiple cold storages need to meet the conditions. If the temperature of any cold storage in the same system does not meet the conditions, no adjustment will be made.

[0070] S7: Record the energy level change trend of each refrigeration compressor, ensure that the energy level of the refrigeration compressor operates at the point of maximum efficiency, and adjust one of the refrigeration compressors.

[0071] S8: When multiple fluorine ceiling-mounted air coolers 3 in the same cold storage need to be defrosted, defrost them one by one to ensure that there is a fluorine ceiling-mounted air cooler 3 that is refrigerating, which can minimize the temperature fluctuation of the cold storage.

[0072] Embodiment 3

[0073] When there are multiple controllers and data needs to be transmitted to the host computer, use a communication cable to connect the 485 communication terminals A and B respectively in the order of the communication wiring diagram (reference Figure 4 ). Radial star connection is not allowed. The communication cable is longer than 300 meters, and terminal resistors R = 100 ohms are added to the beginning and end of the 485 communication port. The shielding net of the communication shield wire should be reliably connected and grounded at one point in the control room.

[0074] As described above, only the specific preferred embodiments of the present invention are provided, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and all should be covered by the protection scope of the present invention.

Claims

1. An energy-saving quick-freezing cold storage, characterized in that, It includes refrigeration room, 1# freezer and 2# freezer. 1# freezer and 2# freezer are set up independently. The refrigeration room is connected to 1# freezer and 2# freezer for refrigeration control. The refrigeration room comprises a refrigeration compressor unit (1) and an evaporative condenser (2) connected to each other; The 1# freezer comprises a plurality of fluorine ceiling-mounted air coolers (3), wherein the plurality of fluorine ceiling-mounted air coolers (3) are respectively connected to the refrigeration compressor unit (1) and the evaporative condenser (2) through pipelines; The 2# freezer comprises a plurality of fluorine ceiling-mounted air coolers (3), wherein the plurality of fluorine ceiling-mounted air coolers (3) are respectively connected to the refrigeration compressor unit (1) and the evaporative condenser (2) through pipelines; The energy-saving quick-freezing cold storage adopts the following control method: Definition: T N : Temperature; F N : Number of operating fluorine ceiling-mounted cooling fans; T 实时 : Real-time temperature; T 设定 : Set temperature; MIN njs : Minimum energy level set point; S1: Read the temperatures T1... T of Freezer 1 and Freezer 2 N ; S2: Determine the temperature change trend of 1# freezer and 2# freezer; S3: Read T 实时 with T 设定 and compare the two; specifically: The automatic cooling program of the refrigeration compressor is divided into two processes: ① rapid cooling process; ② steady-state cooling process; during these two cooling processes, the target temperature of the steady-state cooling is set as T by the host computer. 设定1 The target temperature of the rapid cooling is set as T by the host computer. 设定2 The average outlet air temperature T is obtained by measuring the cold storage value in real time through the temperature sensor. 平均 The difference between the target temperature of the steady-state cooling and the target temperature of the rapid cooling is set as T3 by the host computer, and T 设定2 = T 设定1 + T3; before performing the rapid cooling action, T 设定1 and T3 are manually input. When T 平均 = T 设定2 , after a time delay, it automatically switches to the steady-state cooling process, and the refrigeration parameters required for the steady-state cooling are input into the controllers of each refrigeration device, and finally the stable control of T 平均 = T 设定1 is achieved. S4: According to the temperature changes of 1# freezer and 2# freezer, when the set lower limit temperature is reached gradually, the refrigeration compressors are unloaded one by one and a shutdown signal is output; S5: When only one refrigeration compressor is unloaded to less than MIN njs , determine whether there is a cold storage with a rising temperature trend; S6: When the refrigeration quantity of the fluorine ceiling-mounted cooler (3) in the freezer is less than F N at the set time, call the energy-saving control algorithm subroutine and output the corresponding control; the energy-saving control algorithm subroutine performs the following steps: Ss1: Set the increase or decrease range of the control set value of the refrigeration compressor; Ss2: Set the upper and lower limits of the temperature of the freezer to meet the floating control set value of the refrigeration compressor; Ss3: Regularly detect the cold storage temperature, accumulate the number of times the cold storage temperature is lower than the lower limit and higher than the upper limit, and when the percentage limit of the set number is reached, adjust the number of heads of the refrigeration compressor in operation; Ss4: Through data accumulation, convolutional neural networks are used to analyze big data and output self-learning and adaptive dynamic control strategies; The dynamic control strategy includes: defining the storage temperature Ti of the freezer, the required temperature Tj, and the incoming temperature Tz of the stored items; considering ΔT1=Tz-Tj as the main parameter, defining 4 changes of ΔT1, namely positive large, medium, positive small, and zero, to represent the refrigeration state; using ΔT2=Ti-Tj as real-time fine-tuning; ΔT2 also defines the same 4 languages ​​as ΔT1, and the refrigeration compressor will not stop as long as it is not in the zero zone; when the load is large, the adjustment time is long, and when the load is small, the adjustment time is short; S7: Record the energy level change trend of each refrigeration compressor to ensure that the energy level of the refrigeration compressor operates at the point of maximum efficiency, and adjust one of the refrigeration compressors.

2. The energy-saving quick-freezing cold storage according to claim 1, characterized in that, The refrigeration compressor unit (1) is a fluorine three-head parallel screw unit, comprising: a gas-liquid separator (1.1), a head (1.2), a self-contained economizer (1.3) of the unit, an oil separator (1.4), an oil cooling siphon tank (1.5), and a liquid storage tank (1.6); the gas-liquid separator (1.1) is connected to the head (1.2); the head (1.2) is respectively connected to the self-contained economizer (1.3) and the oil separator (1.4) of the unit; the oil separator (1.4) is connected to the oil cooling siphon tank (1.5); the self-contained economizer (1.3) of the unit is connected to the liquid storage tank (1.6); and the oil cooling siphon tank (1.5) is in communication with the liquid storage tank (1.6).

3. The energy-saving quick-freezing cold storage according to claim 2, wherein, The oil separator (1.4) is connected to the evaporative condenser (2) via a pipeline, and the oil cooling siphon tank (1.5) is connected to the connecting pipeline between the oil separator (1.4) and the evaporative condenser (2) via a pipeline.

4. The energy-saving quick-freezing cold storage according to claim 3, wherein, One side of the evaporative condenser (2) is connected to the oil cooling siphon tank (1.5) and the liquid storage tank (1.6) through pipelines.

5. The energy-saving quick-freezing cold storage according to claim 4, wherein, The gas-liquid separator (1.1) is connected to each fluorine ceiling-type air cooler (3) of the 1# freezer and the 2# freezer through pipelines; each fluorine ceiling-type air cooler (3) of the 1# freezer and the 2# freezer is connected to the connecting pipeline between the oil separator (1.4) and the evaporative condenser (2) through pipelines; the self-contained economizer (1.3) of the unit is connected to each fluorine ceiling-type air cooler (3) of the 1# freezer and the 2# freezer through pipelines; each fluorine ceiling-type air cooler (3) of the 1# freezer and the 2# freezer is connected to the connecting pipeline between the evaporative condenser (2) and the oil cooling siphon tank (1.5) and the liquid storage tank (1.6) through pipelines.

6. The energy-saving quick-freezing cold storage according to claim 5, characterized in that, A fluorine-adding pipeline (4) is connected to the pipeline between the self-contained economizer (1.3) of the unit and the fluorine ceiling-type air coolers (3) of the No. 1 freezer and the No. 2 freezer, and a fluorine-adding port is provided at one end of the fluorine-adding pipeline (4).

7. The energy-saving quick-freezing cold storage according to claim 5, characterized in that, A temperature sensor is installed at the return air point below the fluorine ceiling air cooler (3); each fluorine ceiling air cooler (3) is provided with a thermal relay for overcurrent protection, and the setting value of the thermal relay is 0.95-1.03 times the rated current; and the motor of each fluorine ceiling air cooler (3) is provided with a thermistor protection element for motor thermal protection, and the thermistor protection element is connected in series to the control circuit of the fluorine ceiling air cooler (3).

Images