Cold storage energy consumption monitoring method and system

Abstract

The present invention relates to the field of cold storage technology, and provides a method and system for monitoring energy consumption of cold storage. The method comprises the following steps: obtaining the actual inner and outer temperatures of at least one enclosure structure of the cold storage; calculating the heat flux density of the enclosure structure under preset working conditions; obtaining the flow rate of the refrigerant in the refrigeration system of the cold storage, the temperature and pressure of the refrigerant at the outlets of the condenser and evaporator, and the actual power consumption of the compressor; calculating the coefficient of performance of the compressor under preset working conditions; calculating the power consumption generated by the heat load of the enclosure structure under preset working conditions; obtaining the actual power consumption of other equipment in the refrigeration system except the compressor; calculating the power consumption of other equipment in the refrigeration system except the compressor under preset working conditions; calculating the static power consumption per unit volume of the cold storage under preset working conditions. The system comprises a cold storage and a refrigeration system. The present invention can objectively and truly reflect the energy consumption level of the cold storage, and avoid the influence of factors such as the operation mode, region, function, and use conditions of the cold storage.

Description

Technical Field

[0001] The present invention relates to the technical field of cold storage, and in particular to a method and system for monitoring energy consumption of cold storage. Background Art

[0002] As of 2019, the total volume of cold storage in my country has exceeded 50 million tons, and is still growing at a relatively fast rate. Cold storage energy consumption has become an important node in the field of refrigeration and freezing. Therefore, scientific and objective monitoring of cold storage energy consumption levels is an important prerequisite for discovering cold storage energy consumption problems, improving cold storage performance levels, and achieving energy conservation and emission reduction.

[0003] At present, most cold storages judge their energy consumption levels by monitoring their power consumption. However, the amount of power consumption is not only related to the operation mode of the cold storage, but also affected by factors such as region, cold storage function, and usage conditions. It is impossible to objectively and truly reflect the energy consumption level of the cold storage. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art. To this end, the present invention proposes a cold storage energy consumption monitoring method to objectively and truly reflect the energy consumption level of the cold storage.

[0005] The invention also provides a cold storage energy consumption monitoring system.

[0006] According to the first embodiment of the present invention, the cold storage energy consumption monitoring method comprises the following steps:

[0007] The first acquisition step: obtaining the actual inner and outer temperatures of at least one enclosure structure of the cold storage;

[0008] A first calculation step: calculating the heat flux density of the enclosure structure under a preset working condition according to the parameters obtained in the first acquisition step and the temperature difference between the inside and outside of the enclosure structure under a preset working condition;

[0009] The second acquisition step: acquiring the flow rate of the refrigerant in the refrigeration system of the cold storage, the temperature and pressure of the refrigerant at the outlets of the condenser and the evaporator, and the actual power consumption of the compressor;

[0010] A second calculation step: calculating the coefficient of performance of the compressor under a preset working condition according to the parameters obtained in the second obtaining step;

[0011] The third calculation step: calculating the power consumption generated by the heat load of the enclosure structure under the preset working condition according to the parameters obtained in the first obtaining step, the temperature difference between the inside and outside of the enclosure structure under the preset working condition, and the performance coefficient of the compressor under the preset working condition;

[0012] The third acquisition step: acquiring the actual power consumption of other equipment in the refrigeration system except the compressor;

[0013] Fourth calculation step: calculating the power consumption of other equipment in the refrigeration system except the compressor under the preset working condition according to the parameters obtained in the first obtaining step, the parameters obtained in the third obtaining step and the temperature difference between the inside and outside of the enclosure structure under the preset working condition;

[0014] The fifth calculation step: calculate the static power consumption per unit volume of the cold storage under the preset working conditions based on the power consumption generated by the heat load of the enclosure structure under the preset working conditions, the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions, and the volume of the cold storage.

[0015] According to the cold storage energy consumption monitoring method of the embodiment of the present invention, based on the temperature difference between the inside and outside of the enclosure structure under preset working conditions, starting from the two directions of the cold storage enclosure structure and the refrigeration system, the static power consumption of the cold storage under the preset working conditions is obtained by calculating the power consumption generated by the heat load of the enclosure structure under the preset working conditions and the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions, and then on this basis, it is divided by the volume of the cold storage to eliminate the influence of the volume of the cold storage. Therefore, by comparing the size of the static power consumption per unit volume of the cold storage, the energy consumption level of the cold storage can be objectively and truly reflected, avoiding the influence of factors such as the operation mode, region, function, and use conditions of the cold storage.

[0016] In addition, the cold storage energy consumption monitoring method according to the embodiment of the present invention may also have the following additional technical features:

[0017] According to one embodiment of the present invention, the first calculating step comprises:

[0018] Obtain the heat flux density q1 of the enclosure structure under actual working conditions;

[0019] The heat flux density q of the enclosure structure under the preset working conditions is calculated according to the following formula:

[0020]

[0021] Among them, q represents the heat flux density of the enclosure structure under the preset working conditions, q1 represents the heat flux density of the enclosure structure under the actual working conditions, ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working conditions, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure.

[0022] According to one embodiment of the present invention, the third calculation step comprises:

[0023] Obtain the heat flux density q1 of the enclosure structure under actual working conditions;

[0024] The power consumption E generated by the heat load of the enclosure structure under the preset working conditions is calculated according to the following formula:

[0025]

[0026] Wherein, E represents the power consumption generated by the heat load of the enclosure structure under the preset working conditions, q1 represents the heat flux density of the enclosure structure under the actual working conditions, A represents the heat transfer area of ​​the enclosure structure, COP represents the coefficient of performance of the compressor under the preset working conditions, ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working conditions, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure.

[0027] According to one embodiment of the present invention, the heat flux density of the enclosure structure under actual working conditions is obtained based on a heat flux meter provided in the cold storage, or based on the following formula:

[0028]

[0029] Wherein, λ represents the thermal conductivity of the enclosure structure, and δ represents the thickness of the enclosure structure.

[0030] According to one embodiment of the present invention, the second calculating step comprises:

[0031] Determining the specific enthalpy h1 of the refrigerant at the condenser outlet according to the temperature and pressure of the refrigerant at the condenser outlet in the refrigeration system;

[0032] Determining the specific enthalpy h2 of the refrigerant at the evaporator outlet according to the temperature and pressure of the refrigerant at the evaporator outlet in the refrigeration system;

[0033] The refrigeration capacity Q1 of the compressor in the refrigeration system under actual working conditions is calculated according to the following formula:

[0034] Q1=G*ρ*(h2-h1) / 3600 (4);

[0035] The coefficient of performance COP1 of the compressor under actual working conditions is calculated according to the following formula:

[0036] COP1 = Q1 / E1 (5);

[0037] The coefficient of performance (COP) of the compressor under the preset working conditions is calculated according to the following formula:

[0038] COP = C*COP1 (6);

[0039] Wherein, Q1 represents the refrigeration capacity of the compressor in the refrigeration system under actual working conditions, G represents the refrigerant flow rate in the refrigeration system, ρ represents the refrigerant density in the refrigeration system, h1 represents the specific enthalpy of the refrigerant at the outlet of the condenser, and h2 represents the specific enthalpy of the refrigerant at the outlet of the evaporator; COP1 represents the coefficient of performance of the compressor under actual working conditions, E1 represents the actual power consumption of the compressor; COP represents the coefficient of performance of the compressor under preset working conditions, and C represents the working condition correction factor.

[0040] According to one embodiment of the present invention, the fourth calculation step comprises:

[0041] Calculate the power consumption E' of other equipment in the refrigeration system except the compressor under the preset working conditions according to the following formula:

[0042]

[0043] Wherein, E′ represents the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions, E2 represents the actual power consumption of other equipment in the refrigeration system except the compressor, ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working conditions, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure.

[0044] According to one embodiment of the present invention, the fifth calculation step comprises:

[0045] The static power consumption SEC of the cold storage under the preset working conditions is calculated according to the following formula:

[0046] SEC = E + E′ (8);

[0047] The static power consumption per unit volume of the cold storage under the preset working conditions is calculated according to the following formula: V :

[0048]

[0049] Among them, SEC V It represents the static power consumption per unit volume of the cold storage under the preset working conditions, SEC represents the static power consumption of the cold storage under the preset working conditions, E represents the power consumption caused by the heat load of the enclosure structure under the preset working conditions, E′ represents the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions; V represents the volume of the cold storage.

[0050] According to one embodiment of the present invention, the enclosure structure includes at least one of a cold storage wall, a cold storage door and a cold storage floor.

[0051] According to the cold storage energy consumption monitoring system of the second embodiment of the present invention, it includes a cold storage, a refrigeration system, a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor, a first pressure sensor, a second pressure sensor, a flow meter and an electric meter assembly; the refrigeration system includes a compressor, a condenser, a throttling mechanism and an evaporator, and the compressor, the condenser, the throttling mechanism and the evaporator are connected in sequence end to end to form a refrigeration cycle loop; the flow meter is arranged in the refrigeration cycle loop, and the evaporator is arranged in the cold storage; the third temperature sensor is arranged at the outlet of the condenser, the fourth temperature sensor is arranged at the inlet of the evaporator, the first pressure sensor and the second pressure sensor are respectively arranged at the inlet of the condenser and the outlet of the evaporator, the first temperature sensor and the second temperature sensor are respectively arranged on the inner surface and the outer surface of the enclosure structure of the cold storage, and the electric meter assembly is used to detect the power consumption of each device in the refrigeration system.

[0052] According to one embodiment of the present invention, a heat flow meter is also included in the cold storage.

[0053] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0054] The present invention is based on the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, starting from the two directions of the cold storage enclosure structure and the refrigeration system, and obtains the static power consumption of the cold storage under the preset working conditions by calculating the power consumption generated by the heat load of the enclosure structure under the preset working conditions and the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions. On this basis, it is divided by the volume of the cold storage to exclude the influence of the volume of the cold storage. Therefore, by comparing the size of the static power consumption per unit volume of the cold storage, the energy consumption level of the cold storage can be objectively and truly reflected, avoiding the influence of factors such as the operation mode, region, function and use conditions of the cold storage.

[0055] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0057] Figure 1 It is a flow chart of a cold storage energy consumption monitoring method provided by an embodiment of the present invention;

[0058] Figure 2 It is a structural schematic diagram of a cold storage energy consumption monitoring system provided by an embodiment of the present invention.

[0059] Reference numerals:

[0060] 1. Cold storage; 1.1. Cold storage wall; 1.2. Cold storage door; 1.3. Cold storage floor;

[0061] 2. Compressor; 3. Condenser; 4. Throttling mechanism; 5. Evaporator; 6. Flow meter;

[0062] 7. A third temperature sensor; 8. A fourth temperature sensor; 9. A first pressure sensor;

[0063] 10. A second pressure sensor; 11. A first temperature sensor;

[0064] 12. Second temperature sensor; 13. Heat flow meter. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the invention clearer, the technical solution in the invention will be clearly described below in conjunction with the drawings in the invention. Obviously, the described embodiments are part of the embodiments of the invention, not all of the embodiments. Based on the embodiments in the invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the invention.

[0066] In the description of the embodiments of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "inside", "outside", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0067] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0069] like Figure 1 As shown, an embodiment of the present invention provides a cold storage energy consumption monitoring method, the method comprising the following steps:

[0070] Step 100 is the first acquisition step: obtaining the actual inner and outer temperatures of at least one enclosure structure of the cold storage; wherein, Figure 2 As shown, the enclosure structure includes at least one of the cold storage wall 1.1, the cold storage door 1.2 and the cold storage floor 1.3. For example, a first temperature sensor 11 can be installed on the inner surface of the cold storage wall 1.1, the cold storage door 1.2 and the cold storage floor 1.3, and a second temperature sensor 12 can be installed on the outer surface thereof to monitor the actual inner and outer temperatures of the enclosure structure in real time;

[0071] Step 200 is the first calculation step: according to the parameters obtained in the first acquisition step and the temperature difference between the inside and outside of the enclosure structure under the preset working condition, calculate the heat flux density of the enclosure structure under the preset working condition, specifically: S1, obtain the heat flux density q1 of the enclosure structure under the actual working condition; wherein, the heat flux density q1 can be directly detected by the heat flux meter 13, or calculated by the heat conduction formula q1=λ*ΔT1 / δ=λ*(t1-t2) / δ, wherein λ represents the thermal conductivity of the enclosure structure, δ represents the thickness of the enclosure structure, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working condition, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure. S2, calculate the heat flux density q of the enclosure structure under the preset working condition according to the following formula: q=q1*ΔT / ΔT1=q1*ΔT / (t1-t2), wherein ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working condition, and ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working condition. In addition, it should be noted that the temperature difference ΔT between the inside and outside of the enclosure structure under the preset working conditions can be set based on historical experience and actual conditions. For example, assuming that the preset working conditions are an evaporation temperature of -25°C and a condensation temperature of 35°C, then under this preset working condition, the temperatures inside and outside the cold storage are -18°C and 25°C respectively, then ΔT = 25-(-18) = 43°C.

[0072] Step 300 is the second acquisition step: acquiring the flow rate of the refrigerant in the refrigeration system of the cold storage 1, the temperature and pressure of the refrigerant at the outlets of the condenser 3 and the evaporator 5, and the actual power consumption of the compressor 2. The above parameters can be acquired by installing corresponding detection equipment in the refrigeration system of the cold storage 1, for example, Figure 2 As shown, for the condenser 3, a third temperature sensor 7 can be installed at the outlet of the condenser 3 to obtain the temperature of the refrigerant at the outlet of the condenser 3 in real time; since it can be seen from the pressure-enthalpy diagram that the pressure of the refrigerant at the outlet and the inlet of the condenser 3 is the same, a first pressure sensor 9 can be installed at the inlet of the condenser 3 to obtain the pressure of the refrigerant at the outlet of the condenser 3 in real time. Of course, the first pressure sensor 9 can also be directly installed at the outlet of the condenser 3. Similarly, for the evaporator 5, a second pressure sensor 10 can be installed at the outlet of the evaporator 5 to obtain the pressure of the refrigerant at the outlet of the evaporator 5 in real time. In addition, according to the pressure-enthalpy diagram, it can be seen that the temperature of the refrigerant at the inlet and outlet of the evaporator 5 in the gas-liquid two-phase region is the same, so a fourth temperature sensor 8 can be installed at the inlet of the evaporator 5 to obtain the temperature of the refrigerant at the outlet of the evaporator 5 in real time; of course, the fourth temperature sensor 8 can also be directly installed at the outlet of the evaporator 5. In addition, the actual power consumption of the compressor 2 can be detected in real time by installing an electric meter on the compressor 2, and the flow rate of the refrigerant in the refrigeration system can also be obtained by installing a flow meter 6 in the refrigeration cycle loop. For example, the flow meter 6 can be installed on the pipeline between the condenser 3 and the compressor 2. Of course, the flow meter 6 can also be installed at other locations in the refrigeration cycle loop.

[0073] Step 400 is the second calculation step: according to the parameters obtained in the second acquisition step, the performance coefficient of the compressor 2 under the preset working condition is calculated, specifically: S1, according to the temperature and pressure of the refrigerant at the outlet of the condenser 3 in the refrigeration system, the specific enthalpy h1 of the refrigerant at the outlet of the condenser 3 is determined by querying the pressure-enthalpy diagram; S2, according to the temperature and pressure of the refrigerant at the outlet of the evaporator 5 in the refrigeration system, the specific enthalpy h2 of the refrigerant at the outlet of the evaporator 5 is determined by querying the pressure-enthalpy diagram; S3, the cooling capacity Q1 of the compressor 2 in the refrigeration system under the actual working condition is calculated according to the following formula: Q1=G*ρ*(h 2-h1) / 3600, where G represents the refrigerant flow rate in the refrigeration system, and ρ represents the refrigerant density in the refrigeration system; S4. Calculate the coefficient of performance COP1 of the compressor 2 under actual working conditions according to the following formula: COP1=Q1 / E1, where E1 represents the actual power consumption of the compressor 2; S5. Calculate the coefficient of performance COP of the compressor 2 under preset working conditions according to the following formula: COP=C*COP1, where C represents the working condition correction coefficient, and the working condition correction coefficient C can be determined according to the type of the compressor 2, the actual use environment of the compressor 2 and the type of refrigerant.

[0074] Step 500 is the third calculation step: according to the parameters obtained in the first acquisition step, the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, and the performance coefficient of the compressor 2 under the preset working conditions, the power consumption generated by the heat load of the enclosure structure under the preset working conditions is calculated. Specifically: S1, obtain the heat flux density q1 of the enclosure structure under the actual working conditions; as in step 200, the heat flux density q1 can be directly detected by the heat flux meter 13, and can also be obtained by calculation through the thermal conductivity formula, which will not be repeated here. S2. Calculate the power consumption E generated by the heat load of the enclosure structure under the preset working conditions according to the following formula: E = (q1*A) / COP*ΔT / ΔT1 = (q1*A) / COP*ΔT / (t1-t2), wherein A represents the heat transfer area of ​​the enclosure structure, COP represents the performance coefficient of compressor 2 under the preset working conditions, ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working conditions, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure.

[0075] Step 600 is the third acquisition step: obtaining the actual power consumption of other devices in the refrigeration system except the compressor 2. For example, if the condenser 3 and the evaporator 5 in the refrigeration system are heat exchangers with fans, then electric meters need to be installed on the condenser 3 and the evaporator 5, respectively. In addition, if a driving pump is also provided in the refrigeration system, an electric meter also needs to be installed on the driving pump.

[0076] Step 700 is the fourth calculation step: according to the parameters obtained in the first acquisition step, the parameters obtained in the third acquisition step and the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, calculate the power consumption of other equipment in the refrigeration system except compressor 2 under the preset working conditions. Specifically: calculate the power consumption E′ of other equipment in the refrigeration system except compressor 2 under the preset working conditions according to the following formula: E′ / E2=ΔT / ΔT1=ΔT / (t1-t2), wherein E2 represents the actual power consumption of other equipment in the refrigeration system except compressor 2, ΔT represents the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, ΔT1 represents the temperature difference between the inside and outside of the enclosure structure under the actual working conditions, t1 represents the actual outside temperature of the enclosure structure, and t2 represents the actual inside temperature of the enclosure structure.

[0077] Step 800 is the fifth calculation step: according to the power consumption generated by the heat load of the enclosure structure under the preset working conditions, the power consumption of other equipment in the refrigeration system except the compressor 2 under the preset working conditions, and the volume of the cold storage 1, the static power consumption per unit volume of the cold storage 1 under the preset working conditions is calculated. Specifically: S1. The static power consumption SEC of the cold storage 1 under the preset working conditions is calculated according to the following formula: SEC=E+E′; S2. The static power consumption SEC per unit volume of the cold storage 1 under the preset working conditions is calculated according to the following formula V :SEC V=SEC / V, where E represents the power consumption generated by the heat load of the enclosure structure under the preset working conditions, E′ represents the power consumption of other equipment in the refrigeration system except the compressor 2 under the preset working conditions; V represents the volume of the cold storage 1.

[0078] From the above, it can be seen that the cold storage energy consumption monitoring method in the embodiment of the present invention is based on the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, starting from the two directions of the cold storage enclosure structure and the refrigeration system, by calculating the power consumption generated by the heat load of the enclosure structure under the preset working conditions and the power consumption of other equipment in the refrigeration system except compressor 2 under the preset working conditions to obtain the static power consumption of the cold storage under the preset working conditions, and then on this basis, divided by the volume of the cold storage to eliminate the influence of the volume of the cold storage, thereby comparing the size of the static power consumption per unit volume of the cold storage, the energy consumption level of the cold storage 1 can be objectively and truly reflected, avoiding the influence of factors such as the operation mode, region, function and usage conditions of the cold storage.

[0079] Furthermore, if Figure 2 As shown, an embodiment of the present invention further provides a cold storage energy consumption monitoring system, which includes a cold storage 1, a refrigeration system, a first temperature sensor 11, a second temperature sensor 12, a third temperature sensor 7, a fourth temperature sensor 8, a first pressure sensor 9, a second pressure sensor 10, a flow meter 6 and an electric meter assembly; the refrigeration system includes a compressor 2, a condenser 3, a throttling mechanism 4 and an evaporator 5, and the compressor 2, the condenser 3, the throttling mechanism 4 and the evaporator 5 are connected end to end in sequence to form a refrigeration cycle loop; the flow meter 6 is arranged in the refrigeration cycle loop, and the evaporator 5 is arranged in the cold storage 1; the third temperature sensor 7 is arranged at the outlet of the condenser 3, the fourth temperature sensor 8 is arranged at the inlet of the evaporator 5, the first pressure sensor 9 and the second pressure sensor 10 are respectively arranged at the inlet of the condenser 3 and the outlet of the evaporator 5, the first temperature sensor 11 and the second temperature sensor 12 are respectively arranged on the inner surface and the outer surface of the enclosure structure of the cold storage 1, and the electric meter assembly is used to detect the power consumption of each device in the refrigeration system.

[0080] The first temperature sensor 11, the second temperature sensor 12, the third temperature sensor 7 and / or the fourth temperature sensor 8 may be, but are not limited to, detection devices such as thermocouples, platinum resistance, infrared thermal imaging, etc. The flow meter 6 may be, but is not limited to, ultrasonic liquid flow meter, ultrasonic gas flow meter, and other flow meters embedded in the refrigeration cycle.

[0081] Furthermore, the system also includes a heat flow meter 13 arranged in the cold storage 1.

[0082] The cold storage energy consumption monitoring system in the embodiment of the present invention is based on the temperature difference between the inside and outside of the enclosure structure under preset working conditions, starting from the two directions of the cold storage enclosure structure and the refrigeration system, by adopting an electric meter component, and respectively arranging a first temperature sensor 11 and a second temperature sensor 12 on the inner and outer surfaces of the cold storage enclosure structure, and arranging a fourth temperature sensor 8, a third temperature sensor 7, a first pressure sensor 9, a second pressure sensor 10 and a flow meter 6 in the refrigeration cycle loop of the refrigeration system. The static power consumption per unit volume of the cold storage can be calculated based on the detection values ​​of the above-mentioned detection equipment, and then by comparing the size of the static power consumption per unit volume of the cold storage, the energy consumption level of the cold storage 1 can be objectively and truly reflected, avoiding the influence of factors such as the operation mode, region, cold storage function, and usage conditions of the cold storage 1.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the invention rather than to limit it. Although the invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the invention.

Claims

1. A method for monitoring energy consumption of cold storage, characterized in that: The following steps are involved: The first acquisition step: obtaining the actual internal and external temperatures of at least one enclosure structure of the cold storage, wherein the enclosure structure includes at least one of the cold storage wall, the cold storage door and the cold storage floor; A first calculation step: calculating the heat flux density of the enclosure structure under a preset working condition according to the parameters obtained in the first acquisition step and the temperature difference between the inside and outside of the enclosure structure under a preset working condition; Obtain the heat flux density of the enclosure structure under actual working conditions ; The heat flux density of the enclosure structure under the preset working conditions is calculated according to the following formula : （1）； in, represents the heat flux density of the enclosure structure under the preset working conditions, represents the heat flux density of the enclosure structure under actual working conditions, Indicates the temperature difference between the inside and outside of the enclosure structure under the preset working conditions, Indicates the temperature difference between the inside and outside of the enclosure structure under actual working conditions, represents the actual outside temperature of the enclosure structure, represents the actual inside temperature of the enclosure structure; The second acquisition step: acquiring the flow rate of the refrigerant in the refrigeration system of the cold storage, the temperature and pressure of the refrigerant at the outlets of the condenser and the evaporator, and the actual power consumption of the compressor; The second calculation step: calculating the coefficient of performance of the compressor under the preset working conditions according to the parameters obtained in the second acquisition step; determining the specific enthalpy of the refrigerant at the condenser outlet according to the temperature and pressure of the refrigerant at the condenser outlet in the refrigeration system ; Determine the specific enthalpy of the refrigerant at the evaporator outlet according to the temperature and pressure of the refrigerant at the evaporator outlet in the refrigeration system ; The refrigeration capacity of the compressor in the refrigeration system under actual working conditions is calculated according to the following formula: : / 3600 （4）； The performance coefficient of the compressor under actual working conditions is calculated according to the following formula : （5）； The performance coefficient of the compressor under the preset working conditions is calculated according to the following formula : （6）； in Indicates the refrigeration capacity of the compressor in the refrigeration system under actual working conditions, represents the refrigerant flow rate in the refrigeration system, represents the density of the refrigerant in the refrigeration system, represents the specific enthalpy of the refrigerant at the condenser outlet, It represents the specific enthalpy of the refrigerant at the evaporator outlet; Indicates the coefficient of performance of the compressor under actual working conditions, Indicates the actual power consumption of the compressor; represents the coefficient of performance of the compressor under the preset working conditions, Indicates the working condition correction factor; The third calculation step: calculating the power consumption generated by the heat load of the enclosure structure under the preset working condition according to the parameters obtained in the first obtaining step, the temperature difference between the inside and outside of the enclosure structure under the preset working condition, and the performance coefficient of the compressor under the preset working condition; The power consumption E generated by the heat load of the enclosure structure under the preset working conditions is calculated according to the following formula: （2）； Wherein, E represents the power consumption generated by the heat load of the enclosure structure under the preset working conditions, and A represents the heat transfer area of ​​the enclosure structure; The third acquisition step: acquiring the actual power consumption of other equipment in the refrigeration system except the compressor; Fourth calculation step: Calculate the power consumption of other equipment in the refrigeration system except the compressor under the preset working condition according to the parameters obtained in the first obtaining step, the parameters obtained in the third obtaining step and the temperature difference between the inside and outside of the enclosure structure under the preset working condition; Calculate the power consumption of other equipment in the refrigeration system except the compressor under the preset working condition according to the following formula : （7）； in, Indicates the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions, Indicates the actual power consumption of other equipment in the refrigeration system except the compressor; Fifth calculation step: Calculate the static power consumption per unit volume of the cold storage under the preset working conditions according to the power consumption generated by the heat load of the enclosure structure under the preset working conditions, the power consumption of other equipment in the refrigeration system except the compressor under the preset working conditions, and the volume of the cold storage. Calculate the static power consumption SEC of the cold storage under the preset working conditions according to the following formula: （8）； Calculate the static power consumption per unit volume of the cold storage under the preset working conditions according to the following formula: : （9）； in, Indicates the static power consumption per unit volume of the cold storage under the preset working conditions, Indicates the static power consumption of the cold storage under the preset working conditions, Indicates the volume of the cold storage.

2. The cold storage energy consumption monitoring method according to claim 1 is characterized in that: The heat flux density of the enclosure structure under actual working conditions is obtained based on a heat flux meter provided in the cold storage, or based on the following formula: （3）； in, represents the thermal conductivity of the enclosure structure, Indicates the thickness of the enclosure structure.

3. A cold storage energy consumption monitoring system based on the cold storage energy consumption monitoring method according to claim 1 or 2, characterized in that: It includes a cold storage, a refrigeration system, a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor, a first pressure sensor, a second pressure sensor, a flow meter and an electric meter assembly; the refrigeration system includes a compressor, a condenser, a throttling mechanism and an evaporator, and the compressor, the condenser, the throttling mechanism and the evaporator are connected end to end in sequence to form a refrigeration cycle; the flow meter is arranged in the refrigeration cycle, and the evaporator is arranged in the cold storage; the third temperature sensor is arranged at the outlet of the condenser, the fourth temperature sensor is arranged at the inlet of the evaporator, the first pressure sensor and the second pressure sensor are respectively arranged at the inlet of the condenser and the outlet of the evaporator, the first temperature sensor and the second temperature sensor are respectively arranged on the inner surface and the outer surface of the enclosure structure of the cold storage, and the electric meter assembly is used to detect the power consumption of each device in the refrigeration system.

4. The cold storage energy consumption monitoring system according to claim 3 is characterized in that: Also included is a heat flow meter arranged in the cold storage.

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