Refrigerator performance prediction method and device, electronic equipment and storage medium

Abstract

The application provides a refrigeration machine performance prediction method and device, electronic equipment and a storage medium, and relates to the technical field of refrigeration. The method comprises the following steps: collecting condensation saturation temperature, evaporation saturation temperature and compression discharge temperature of a refrigeration system in a running test operation process, so as to determine saturated liquid phase specific enthalpy, saturated gas phase specific enthalpy, and overheat gas phase specific enthalpy determined according to the condensation saturation pressure calculated according to the condensation saturation temperature and the compression discharge temperature; performing system refrigeration energy efficiency prediction according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the overheat gas phase specific enthalpy, so as to obtain target system refrigeration energy efficiency; and performing unit performance prediction on a target refrigeration machine by using a target refrigeration performance model, the target system refrigeration energy efficiency, frequency converter efficiency, motor efficiency and bearing transmission efficiency. The application can realize actual refrigeration performance calculation from refrigeration cycle theory to the refrigeration machine unit, effectively solves the problem of refrigeration machine performance prediction deviation, and improves the performance prediction effect of the refrigeration machine.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of refrigeration, and in particular, to a performance prediction method and device for a refrigeration machine, an electronic device, and a storage medium. BACKGROUND

[0002] At present, the performance prediction of a traditional refrigeration machine is performed by a refrigeration machine energy efficiency prediction experience model depending on a refrigeration machine factory performance parameter curve to obtain a refrigeration machine COP and refrigeration load rate, chilled water temperature, cooling water temperature, and the like, and to determine the refrigeration machine energy efficiency according to refrigeration load rate, chilled water temperature, cooling water temperature, and the like measured in real-time operation of the refrigeration machine, by an experience model formula. However, due to the large difference in performance characteristics of different refrigeration machines, even for the same refrigeration machine, the performance characteristics will change over time, and only depending on the refrigeration machine factory performance parameter curve for prediction, with the change in performance characteristics, the refrigeration machine factory performance parameter curve is difficult to accurately reflect the refrigeration of the refrigeration machine in actual operation conditions, resulting in a large error in the refrigeration performance prediction of the refrigeration machine performance, and leading to poor performance prediction effect of the refrigeration machine. Therefore, how to improve the performance prediction effect of the refrigeration machine has become a problem to be solved. SUMMARY

[0003] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a performance prediction method and device for a refrigeration machine, an electronic device, and a storage medium, which improves the performance prediction effect of the refrigeration machine.

[0004] To achieve the above-mentioned purpose, a first aspect of embodiments of the present application provides a performance prediction method for a refrigeration machine, the target refrigeration machine comprising a refrigeration system, the refrigeration system comprising an evaporator, a condenser, and a compressor, the method comprising:

[0005] performing an operation test operation on the target refrigeration machine, and collecting a condensing saturation temperature of the condenser, an evaporating saturation temperature of the evaporator, and a compression discharge temperature of the compressor during the operation test operation;

[0006] performing liquid phase specific enthalpy calculation on the condenser according to the condensing saturation temperature to obtain a saturated liquid phase specific enthalpy;

[0007] performing gas phase specific enthalpy calculation on the evaporator according to the evaporating saturation temperature to obtain a saturated gas phase specific enthalpy;

[0008] performing saturation pressure calculation according to the condensing saturation temperature to obtain a condensing saturation pressure, and performing superheated gas phase specific enthalpy calculation according to the compression discharge temperature and the condensing saturation pressure to obtain a superheated gas phase specific enthalpy;

[0009] According to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy, the refrigeration energy efficiency of the refrigeration system is predicted to obtain target system refrigeration energy efficiency;

[0010] The frequency converter efficiency, the motor efficiency and the bearing transmission efficiency are obtained.

[0011] The target refrigeration machine is predicted in unit performance by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency to obtain unit refrigeration performance prediction data.

[0012] In some embodiments, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency are obtained, including:

[0013] The performance characteristic model of the target refrigeration machine is obtained.

[0014] During the operation test operation of the target refrigeration machine, the unit input electric power and the unit measured rotating speed are collected.

[0015] The unit input electric power and the unit measured rotating speed are substituted into the performance characteristic model to calculate the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency.

[0016] In some embodiments, the refrigeration energy efficiency of the refrigeration system is predicted according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy to obtain target system refrigeration energy efficiency, including:

[0017] The refrigeration capacity of the refrigeration system is calculated according to the saturated gas phase specific enthalpy and the saturated liquid phase specific enthalpy to obtain system specific refrigeration capacity.

[0018] The system shaft work of the refrigeration system is calculated according to the superheated gas phase specific enthalpy and the saturated gas phase specific enthalpy to obtain system specific input work.

[0019] The refrigeration energy efficiency of the refrigeration system is evaluated according to the system specific refrigeration capacity and the system specific input shaft work to obtain the target system refrigeration energy efficiency.

[0020] In some embodiments, the target refrigeration machine is predicted in unit performance by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency to obtain unit refrigeration performance prediction data, including:

[0021] The effective energy efficiency of the target refrigeration machine is calculated by using the target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency to obtain unit refrigeration effective energy efficiency.

[0022] performing refrigeration loss calculation on the target refrigeration machine according to the inverter efficiency, the motor efficiency and the bearing drive efficiency, to obtain a unit refrigeration loss energy efficiency;

[0023] performing refrigeration evaluation on the target refrigeration machine according to the unit refrigeration effective energy efficiency and the unit refrigeration loss energy efficiency, to obtain the unit refrigeration performance prediction data.

[0024] In some embodiments, the performing refrigeration evaluation on the target refrigeration machine according to the unit refrigeration effective energy efficiency and the unit refrigeration loss energy efficiency, to obtain the unit refrigeration performance prediction data, comprises:

[0025] performing unit energy efficiency prediction on the target refrigeration machine according to the unit refrigeration effective energy efficiency and the unit refrigeration loss energy efficiency, to obtain a target unit refrigeration energy efficiency;

[0026] performing refrigeration energy efficiency evaluation on the target refrigeration machine according to the target unit refrigeration energy efficiency and the unit input electric power, to obtain the unit refrigeration performance prediction data.

[0027] In some embodiments, the performing superheat specific enthalpy calculation according to the compression discharge temperature and the condensation saturation pressure, to obtain a superheat gas phase specific enthalpy, comprises:

[0028] obtaining a pressure specific enthalpy coefficient of the condensation saturation pressure, and performing pressure specific enthalpy fitting according to the pressure specific enthalpy coefficient and the condensation saturation pressure, to obtain a pressure specific enthalpy;

[0029] obtaining a pressure-temperature coupling coefficient between the condensation saturation pressure and the compression discharge temperature;

[0030] performing pressure-temperature specific enthalpy fitting according to the pressure-temperature coupling coefficient, the condensation saturation pressure and the compression discharge temperature, to obtain a pressure-temperature coupling specific enthalpy;

[0031] performing specific enthalpy summation according to the pressure specific enthalpy and the pressure-temperature coupling specific enthalpy, to obtain the superheat gas phase specific enthalpy.

[0032] In some embodiments, the obtaining inverter efficiency, motor efficiency and bearing drive efficiency, further comprises:

[0033] obtaining mechanical structure characteristics of the target refrigeration machine, and determining motor efficiency and bearing drive efficiency of the target refrigeration machine based on the mechanical structure characteristics;

[0034] obtaining historical unit refrigeration energy efficiency and historical system refrigeration energy efficiency of the target refrigeration machine;

[0035] The frequency converter efficiency is calculated based on the historical unit refrigeration energy efficiency, the historical system refrigeration energy efficiency, the motor efficiency and the bearing transmission efficiency, to obtain the frequency converter efficiency.

[0036] In a second aspect, the embodiments of the present application provide a performance prediction device of a refrigerating machine, the target refrigerating machine comprising a refrigerating system, the refrigerating system comprising an evaporator, a condenser and a compressor, and comprising:

[0037] The running test temperature collection module is configured to perform a running test operation on the target refrigerating machine, and collect a condensing saturation temperature of the condenser, an evaporating saturation temperature of the evaporator and a compression discharge temperature of the compressor during the running test operation.

[0038] The saturated liquid phase specific enthalpy calculation module is configured to calculate a saturated liquid phase specific enthalpy of the condenser according to the condensing saturation temperature, to obtain the saturated liquid phase specific enthalpy.

[0039] The saturated gas phase specific enthalpy calculation module is configured to calculate a saturated gas phase specific enthalpy of the evaporator according to the evaporating saturation temperature, to obtain the saturated gas phase specific enthalpy.

[0040] The superheated gas phase specific enthalpy calculation module is configured to calculate a condensing saturation pressure according to the condensing saturation temperature, to obtain the condensing saturation pressure, and calculate a superheated gas phase specific enthalpy according to the compression discharge temperature and the condensing saturation pressure, to obtain the superheated gas phase specific enthalpy.

[0041] The system performance prediction module is configured to predict a refrigeration energy efficiency of the refrigerating system according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy, to obtain a target system refrigeration energy efficiency.

[0042] The running efficiency acquisition module is configured to acquire a frequency converter efficiency, a motor efficiency and a bearing transmission efficiency.

[0043] The unit performance prediction module is configured to predict a unit refrigeration performance of the target refrigerating machine by using a pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, to obtain unit refrigeration performance prediction data.

[0044] In a third aspect, the embodiments of the present application provide an electronic device, comprising a memory and a processor, the memory stores a computer program, and the processor implements the performance prediction method of the refrigerating machine according to any one of the embodiments of the first aspect of the present application when executing the computer program.

[0045] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, the storage medium stores a program, and the program is executed by a processor to implement the performance prediction method of the refrigerating machine according to any one of the embodiments of the first aspect of the present application.

[0046] The performance prediction method of the refrigerating machine provided in the application can obtain the thermodynamic parameters reflecting the target refrigerating machine in the running test process, replace the traditional fixed factory curve parameters, eliminate the errors caused by equipment differences and performance changes from the source, calculate the saturated liquid phase specific enthalpy, saturated gas phase specific enthalpy and superheated gas phase specific enthalpy based on the condensation saturation temperature, evaporation saturation temperature and compression discharge temperature, realize the dynamic calculation of the thermophysical properties of the target refrigerating machine, avoid the defects that the fixed parameter curve is difficult to reflect the actual thermodynamic state of the target refrigerating machine, predict the target system refrigeration energy efficiency of the refrigeration system according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy, quantify the theoretical energy efficiency calculation of the refrigeration system cycle, and improve the refrigeration performance prediction accuracy of the refrigeration system. Further, by obtaining the frequency converter efficiency, motor efficiency and bearing transmission efficiency, the refrigeration performance prediction process of the target refrigerating machine is added to the refrigeration performance prediction process, the refrigeration energy change of the target refrigerating machine in the actual operation can be accurately predicted. Finally, by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, the unit performance of the target refrigerating machine is predicted, the actual refrigeration performance calculation from the refrigeration cycle theory to the refrigerating machine unit is realized, the refrigeration performance prediction deviation problem caused by ignoring the dynamic loss and the property change of the target refrigerating machine is effectively solved, the refrigeration performance prediction accuracy of the target refrigerating machine is significantly improved, and the refrigeration performance prediction effect of the target refrigerating machine is improved.

[0047] Other features and advantages of the present application will be set forth in the following description, and in part will be apparent from the description, or can be learned by practice of the present application. The objects and other advantages of the present application will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 is a flowchart of a performance prediction method of a refrigerating machine provided by an embodiment of the present application;

[0049] Figure 2 is a flowchart of a performance prediction method of a refrigerating machine provided by another embodiment of the present application;

[0050] Figure 3 is a flowchart of a performance prediction method of a refrigerating machine provided by another embodiment of the present application;

[0051] Figure 4is a flowchart of a performance prediction method of a refrigerator provided by another embodiment of the present application;

[0052] Figure 5 is a flowchart of a performance prediction method of a refrigerator provided by another embodiment of the present application;

[0053] Figure 6 is a flowchart of a performance prediction method of a refrigerator provided by another embodiment of the present application;

[0054] Figure 7 is a flowchart of a performance prediction method of a refrigerator provided by another embodiment of the present application;

[0055] Figure 8 is a schematic diagram of a performance prediction device of a refrigerator provided by an embodiment of the present application;

[0056] Figure 9 is a hardware structure schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0058] It should be noted that although the functional modules are divided in the device schematic diagram, and the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a manner different from the module division in the device or the order in the flowchart. The terms "first", "second", etc. in the specification and claims and the above-described drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence.

[0059] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application, and are not intended to limit the present application.

[0060] The application is operable in a multitude of various or specific computer system environments or configurations. For example: personal computer, server computer, handheld or portable device, tablet device, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. The application can be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and the like, that perform particular tasks or implement particular abstract data types. The application can also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules can be located in both local and remote computer storage media including memory storage devices.

[0061] At present, the performance prediction of the conventional chiller is performed by a chiller energy efficiency prediction empirical model depending on a chiller factory performance parameter curve to obtain a chiller COP and a refrigeration load rate, a chilled water temperature, a cooling water temperature and the like, and to determine the chiller energy efficiency according to measured data of the refrigeration load rate, the chilled water temperature, the cooling water temperature and the like in real-time running of the chiller by an empirical model formula. However, since there is a large difference in performance characteristics of different chillers, even for the same chiller, the performance characteristics will change over time, and only depending on the chiller factory performance parameter curve for prediction, with the change of the performance characteristics, the chiller factory performance parameter curve is difficult to accurately reflect the refrigeration of the chiller in the actual running condition, so that a large error occurs in the refrigeration performance prediction of the chiller performance, resulting in poor performance prediction effect of the chiller. Therefore, how to improve the performance prediction effect of the chiller becomes a problem to be solved.

[0062] However, the related art adopts an empirical model, only depends on the chiller factory performance parameter curve for prediction, and is difficult to accurately reflect the refrigeration of the chiller in the actual running condition, so that a large error occurs in the refrigeration performance prediction of the chiller performance, resulting in poor performance prediction effect of the chiller. Therefore, how to improve the performance prediction effect of the chiller becomes a problem to be solved.

[0063] Based on this, the embodiments of the application provide a performance prediction method and device based on a chiller, an electronic device and a storage medium, which improve the performance prediction effect of the urban chiller by considering the temperature change, the pressure change and the refrigeration efficiency of the chiller in the running test process.

[0064] The refrigeration machine performance prediction method and device, the electronic equipment and the storage medium provided by the embodiments of the present application are specifically described through the following embodiments. First, the refrigeration machine performance prediction method in the embodiments of the present application is described.

[0065] Figure 1 is an optional flowchart of the refrigeration machine performance prediction method provided by the embodiments of the present application. The target refrigeration machine includes a refrigeration system, and the refrigeration system includes an evaporator, a condenser and a compressor, Figure 1 The method in can include but is not limited to steps S101 to S107.

[0066] Step S101, performing a running test operation on the target refrigeration machine, and collecting the condensing saturation temperature of the condenser, the evaporating saturation temperature of the evaporator and the compression discharge temperature of the compressor during the running test operation.

[0067] Step S102, performing liquid-phase specific enthalpy calculation on the condenser according to the condensing saturation temperature to obtain a saturated liquid-phase specific enthalpy.

[0068] Step S103, performing gas-phase specific enthalpy calculation on the evaporator according to the evaporating saturation temperature to obtain a saturated gas-phase specific enthalpy.

[0069] Step S104, performing saturation pressure calculation according to the condensing saturation temperature to obtain a condensing saturation pressure, and performing superheated gas-phase specific enthalpy calculation according to the compression discharge temperature and the condensing saturation pressure to obtain a superheated gas-phase specific enthalpy.

[0070] Step S105, performing refrigeration energy efficiency prediction on the refrigeration system according to the saturated liquid-phase specific enthalpy, the saturated gas-phase specific enthalpy and the superheated gas-phase specific enthalpy to obtain a target system refrigeration energy efficiency.

[0071] Step S106, obtaining a frequency converter efficiency, a motor efficiency and a bearing transmission efficiency.

[0072] Step S107, performing unit performance prediction on the target refrigeration machine by using a pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency to obtain unit refrigeration performance prediction data.

[0073] The steps S101 to S107 shown in the embodiments of the present application first acquire the thermodynamic parameters reflecting the target refrigerating machine in the running test process by collecting the condensation saturation temperature of the condenser, the evaporation saturation temperature of the evaporator and the compression discharge temperature of the compressor in the running test operation process, instead of the traditional fixed factory curve parameters, to eliminate errors caused by equipment differences and performance changes from the source; secondly, the saturated liquid specific enthalpy, the saturated gas specific enthalpy and the superheated gas specific enthalpy are calculated based on the condensation saturation temperature, the evaporation saturation temperature and the compression discharge temperature, realizing the dynamic calculation of the thermophysical properties of the target refrigerating machine, avoiding the defect that the fixed parameter curve is difficult to reflect the actual thermodynamic state of the target refrigerating machine, and predicting the target system refrigeration energy efficiency of the refrigeration system according to the saturated liquid specific enthalpy, the saturated gas specific enthalpy and the superheated gas specific enthalpy, which can quantify the theoretical energy efficiency calculation of the refrigeration system cycle, so as to improve the refrigeration performance prediction accuracy of the refrigeration system; further, by acquiring the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, the refrigeration performance prediction process is realized by adding the unit refrigeration loss of the target refrigerating machine, which can accurately predict the refrigeration energy change of the target refrigerating machine in actual operation; finally, the unit performance of the target refrigerating machine is predicted by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, which can realize the actual refrigeration performance calculation from the refrigeration cycle theory to the refrigerating machine unit, effectively solve the refrigeration performance prediction deviation problem caused by ignoring the dynamic loss and the property change of the target refrigerating machine, significantly improve the refrigeration performance prediction accuracy of the target refrigerating machine, and thus improve the refrigeration performance prediction effect of the target refrigerating machine.

[0074] In step S101 of some embodiments, specifically, the running test operation means that the target refrigerating machine enters and maintains a stable running state, and the target refrigerating machine is tested to obtain the test parameters of the target refrigerating machine in the running test process.

[0075] Specifically, the condensation saturation temperature refers to the temperature at which the refrigerant reaches a saturated state when it is liquefied in the condenser, at which time the gaseous and liquid states of the refrigerant are in equilibrium.

[0076] Specifically, the evaporation saturation temperature refers to the temperature at which the refrigerant reaches a saturated state when it is vaporized in the evaporator, at which time the liquid and gaseous states of the refrigerant are in equilibrium.

[0077] Specifically, the compression discharge temperature refers to the temperature of the refrigerant when it is discharged from the compressor outlet after being compressed in the compressor.

[0078] Specifically, during the running test operation, the condensation saturation temperature can be obtained from a temperature sensor installed at the inlet and outlet of the condenser, the evaporation saturation temperature can be obtained from a temperature sensor installed at the inlet and outlet of the evaporator, and the compression discharge temperature can be obtained from a temperature sensor installed at the discharge port of the compressor.

[0079] In this embodiment, by performing a running test operation on the target refrigeration machine and collecting the condensation saturation temperature of the condenser, the evaporation saturation temperature of the evaporator, and the compression discharge temperature of the compressor during the running test operation, the thermodynamic parameters during the running test can be directly obtained, replacing the traditional fixed factory curve parameters to eliminate errors caused by equipment differences and performance changes from the source.

[0080] In step S102 of some embodiments, specifically, the saturated liquid phase specific enthalpy refers to the specific enthalpy of unit mass of refrigerant in a saturated state in the condenser at the condensation saturation temperature, which is used to reflect the heat released when the refrigerant is liquefied from a gaseous state to a liquid state. The refrigerant can be a refrigerant.

[0081] Specifically, the saturated liquid phase specific enthalpy can be calculated by a function of the condensation saturation temperature, and can be determined by the following formula:

[0082]

[0083]

[0084] wherein, represents the saturated liquid phase specific enthalpy of the condenser at the saturated liquid state ls of the refrigerant, represents the condensation saturation temperature, in ℃, represents the saturated liquid phase specific enthalpy of unit mass of refrigerant at the saturated liquid state ls of the refrigerant and the condensation saturation temperature , in kJ / kg, represents the constant term coefficient of the saturated liquid phase specific enthalpy and condensation saturation temperature polynomial, represents the first-order term coefficient of the saturated liquid phase specific enthalpy and condensation saturation temperature polynomial, the second-order term coefficient of the saturated liquid phase specific enthalpy and condensation saturation temperature polynomial, represents the third-order term coefficient of the saturated liquid phase specific enthalpy and condensation saturation temperature polynomial.

[0085] For example, for the saturated liquid phase specific enthalpy and condensation saturation temperature polynomial coefficient of the refrigerant R134a, the content in Table 1 below can be used.

[0086] Table 1

[0087]

[0088] In this embodiment, the liquid phase enthalpy of the condenser is calculated based on the condensation saturation temperature to obtain the saturated liquid phase enthalpy. This allows the condensation saturation temperature collected during the operation and testing process to be converted into a parameter that can be directly used for refrigeration energy calculation. This enables more accurate quantification of refrigerant energy prediction for the condenser and provides an important thermophysical data foundation for subsequent refrigeration performance prediction.

[0089] In step S103 of some embodiments, specifically, the saturated gas enthalpy refers to the heat contained in the liquid enthalpy of a unit mass of refrigerant at the saturation temperature when the refrigerant reaches saturation in the evaporator, and is used to reflect the heat absorbed by the refrigerant when it vaporizes from liquid to gas.

[0090] Specifically, the enthalpy of a saturated gas can be calculated as a function of the saturation temperature of evaporation, and can be determined using the following formula:

[0091]

[0092]

[0093] in, This indicates the evaporator under refrigerant saturation gaseous state (gs). Compared to saturated gas, enthalpy This indicates the saturation temperature of evaporation, expressed in °C. This represents the refrigerant saturated gaseous state gs and the condensation saturation temperature. The saturated gaseous enthalpy of a unit mass of refrigerant, expressed in kJ / kg. The constant term coefficients of the polynomial relating the enthalpy of saturated gas to the saturation temperature of evaporation are represented. The coefficients of the first-order term in the polynomial relating the enthalpy of saturated gas to the saturation temperature of evaporation are represented. This represents the coefficient of the quadratic term in the polynomial relating the enthalpy of saturated gas to the saturation temperature of evaporation. This represents the coefficient of the cubic term in the polynomial relating the enthalpy of saturated gas to the saturation temperature of evaporation.

[0094] For example, the polynomial coefficients between the saturated gas enthalpy and the evaporation saturation temperature for refrigerant R134a can be found in Table 2 below.

[0095] Table 2

[0096]

[0097] In this embodiment, the enthalpy of the evaporator is calculated based on the saturation temperature to obtain the saturated enthalpy of the gas phase. This accurately captures the cooling capacity of the refrigerant on the evaporator side and dynamically reflects the characteristics of the working fluid under the actual operating conditions of the target refrigerator. This avoids the calculation errors caused by using a fixed enthalpy value and thus improves the accuracy of subsequent predictions of the cooling performance of the target refrigerator.

[0098] In step S104 of some embodiments, specifically, the condensation saturation pressure refers to the saturation state pressure corresponding to the refrigerant changing from a gaseous state to a liquid state in the condenser, which corresponds to the compression discharge temperature one by one, and is a key thermodynamic parameter of the refrigeration system in the condensation stage of the refrigeration cycle.

[0099] Specifically, the condensation saturation pressure can be calculated by a function of the condensation saturation temperature, and can be determined by the following formula:

[0100]

[0101] wherein, represents the condensation saturation pressure of the refrigerant in the superheated gaseous state s and the condensation saturation temperature , unit: kpa, represents the constant term coefficient of the condensation saturation pressure and the condensation saturation temperature polynomial, represents the first order term coefficient of the condensation saturation pressure and the condensation saturation temperature polynomial, represents the second order term coefficient of the condensation saturation pressure and the condensation saturation temperature polynomial, represents the third order term coefficient of the condensation saturation pressure and the condensation saturation temperature polynomial.

[0102] For example, for the refrigerant R134a, the polynomial coefficients between the condensation saturation pressure and the condensation saturation temperature can be the contents in Table 3 as follows.

[0103] Table 3

[0104]

[0105] Please refer to Figure 4 In some embodiments, step S104 can also include, but is not limited to, steps S201 to S204.

[0106] Step S201, obtaining the pressure ratio enthalpy coefficient of the condensation saturation pressure, and performing pressure ratio enthalpy fitting according to the pressure ratio enthalpy coefficient and the condensation saturation pressure to obtain the pressure ratio enthalpy.

[0107] Step S202, obtaining the pressure-temperature coupling coefficient between the condensation saturation pressure and the compression discharge temperature.

[0108] Step S203, performing pressure-temperature ratio enthalpy fitting according to the pressure-temperature coupling coefficient, the condensation saturation pressure and the compression discharge temperature to obtain the pressure-temperature coupling ratio enthalpy.

[0109] Step S204, performing specific enthalpy summation according to the pressure ratio enthalpy and the pressure-temperature coupling ratio enthalpy to obtain the superheated gaseous phase specific enthalpy.

[0110] In step S201 of some embodiments, specifically, the pressure specific enthalpy coefficient refers to the polynomial coefficient of the superheated gas specific enthalpy and the condensation saturation pressure polynomial, which is used to describe the effect of the condensation saturation pressure on the superheated gas specific enthalpy under superheated conditions.

[0111] Specifically, pressure enthalpy refers to the contribution of only the condensing saturation pressure to the refrigerant's specific enthalpy value.

[0112] In step S202 of some embodiments, specifically, the pressure-temperature coupling coefficient refers to the polynomial coefficients of the condensation saturation pressure, the compression exhaust temperature, and the superheated gas relative enthalpy polynomial, used to describe the combined effect of the condensation saturation pressure and the compression exhaust temperature on the superheated gas relative enthalpy under superheated conditions.

[0113] In step S203 of some embodiments, specifically, the pressure-temperature coupled specific enthalpy refers to the additional contribution of the refrigerant specific enthalpy value, which takes into account the combined influence of the condensation saturation pressure and the compression discharge temperature.

[0114] In step S204 of some embodiments, specifically, the superheated gas relative enthalpy is the outlet enthalpy value of the diffuser in a stagnant state, used to reflect the increase in energy of the refrigerant during compression.

[0115] Specifically, the enthalpy of the superheated gas can be calculated using the condensation saturation pressure and the compression exhaust temperature function, and can be determined using the following formula:

[0116]

[0117] in, This indicates the diffuser in both the superheated gaseous state (s) and the stagnation state (0) of the refrigerant. The relative enthalpy of the superheated gas at the outlet, This indicates the saturated pressure of the refrigerant in its superheated gaseous state (s) and the condensation saturation pressure. and compressed exhaust temperature The superheated gas has a higher enthalpy.

[0118] Therefore, the specific enthalpy of superheated gas can be further expressed as:

[0119]

[0120] in, This indicates the refrigerant temperature in its superheated gaseous state (s), stagnation state (0), and compression discharge temperature. Down diffuser The relative enthalpy of the superheated gas at the outlet, The constant term coefficients of the polynomial relating the relative enthalpy of superheated gas and the saturated pressure of condensation are represented by... This represents the coefficient of the first-order term in the polynomial relating the relative enthalpy of superheated gas to the saturated pressure of condensation. a coefficient of a quadratic term of the polynomial representing the specific enthalpy of the superheated vapor phase, the saturation pressure of condensation, and the temperature of the compressed exhaust gas, a coefficient of a constant term of the polynomial representing the specific enthalpy of the superheated vapor phase, the saturation pressure of condensation, and the temperature of the compressed exhaust gas, a coefficient of a linear term of the polynomial representing the specific enthalpy of the superheated vapor phase, the saturation pressure of condensation, and the temperature of the compressed exhaust gas, a coefficient of a quadratic term of the polynomial representing the specific enthalpy of the superheated vapor phase, the saturation pressure of condensation, and the temperature of the compressed exhaust gas, a coefficient of a cubic term of the polynomial representing the specific enthalpy of the superheated vapor phase, the saturation pressure of condensation, and the temperature of the compressed exhaust gas.

[0121] For example, for the refrigerant R134a, the pressure-specific enthalpy coefficient 、 and , and the pressure-temperature coupling coefficient 、 、 and may be the contents in Table 4 below.

[0122] Table 4

[0123]

[0124] Through steps S201 to S204, the enthalpy value calculation can be converted into a relatively simple enthalpy value algebraic operation, avoiding the difficulty of directly measuring the enthalpy value, not only reducing the requirement for computing resources, but also comprehensively considering the influence of pressure independent and pressure temperature coupling on the specific enthalpy of the superheated vapor phase, which can improve the calculation accuracy of the specific enthalpy of the superheated vapor phase while ensuring the calculation efficiency, and provide reliable data support for the subsequent calculation of system-specific input shaft work and system refrigeration energy efficiency, thereby improving the subsequent refrigeration performance prediction accuracy of the target refrigeration machine.

[0125] Please refer to Figure 3 In some embodiments, step S105 can include, but is not limited to, steps S301 to S304.

[0126] Step S301, according to the specific enthalpy of the saturated vapor phase and the specific enthalpy of the saturated liquid phase, the refrigeration capacity of the refrigeration system is calculated to obtain the system-specific refrigeration capacity.

[0127] Step S302, according to the specific enthalpy of the superheated vapor phase and the specific enthalpy of the saturated vapor phase, the system shaft work of the refrigeration system is calculated to obtain the system-specific input shaft work.

[0128] Step S303, according to the system-specific refrigeration capacity and the system-specific input shaft work, the refrigeration energy efficiency of the refrigeration system is evaluated to obtain the target system refrigeration energy efficiency.

[0129] In step S301 of some embodiments, specifically, the system specific cooling capacity refers to the specific cooling capacity per unit mass of refrigerant in the evaporator of the target refrigerator. It is a key indicator for measuring the thermodynamic performance of the refrigeration cycle of the refrigeration system, and its unit is kJ / kg.

[0130] Specifically, the refrigeration system also includes a throttle valve, and the compressor in the refrigeration system also includes inlet guide vanes.

[0131] Specifically, the system's specific cooling capacity can be calculated using the following formula:

[0132]

[0133] in, Indicates the specific cooling capacity of the system. This represents the gas-phase saturated specific enthalpy at the inlet of the guide vane IGV under the conditions of refrigerant in superheated gaseous state g and stagnation state 0. This represents the liquid phase saturation enthalpy at the inlet of the expansion valve when the refrigerant is in a saturated liquid state (ls).

[0134] Furthermore, since the stagnation enthalpy at the inlet of the guide vane IGV is approximately equal to the saturated gas phase enthalpy of the evaporator, and the liquid phase saturation enthalpy at the inlet of the throttle valve is approximately equal to the liquid phase saturation enthalpy of the condenser, therefore:

[0135]

[0136]

[0137] in, This represents the gas-phase saturated specific enthalpy at the inlet of the guide vane IGV under the conditions of refrigerant in superheated gaseous state g and stagnation state 0. This indicates the evaporator under refrigerant saturation gaseous state (gs). Compared to saturated gas, enthalpy This represents the liquid-phase saturation specific enthalpy at the inlet of the expansion valve when the refrigerant is in a saturated liquid state (ls). This indicates the condenser at saturated liquid refrigerant levels (ls). The enthalpy of a saturated liquid.

[0138] Therefore, the formula for calculating the specific cooling capacity of the system can be further expressed as:

[0139]

[0140] in, Indicates the specific cooling capacity of the system. This represents the saturated gas-phase enthalpy of the evaporator under saturated gaseous refrigerant conditions (gs). This represents the saturated liquid phase enthalpy of the condenser at a refrigerant saturation liquid state (ls).

[0141] In step S302 of some embodiments, specifically, the system specific input shaft work refers to the specific input shaft work corresponding to unit mass refrigerant of the compressor in the refrigeration system, and the unit is kJ / kg.

[0142] Specifically, the system specific input shaft work can be calculated by the following formula:

[0143]

[0144] wherein, represents the system specific input shaft work, represents the specific enthalpy of the superheated gas phase at the inlet of the diffuser VGD in the refrigerant superheated gas state g and the stagnation state 0. represents the specific enthalpy of the superheated gas phase at the outlet of the inlet guide vane IGV in the refrigerant superheated gas state g and the stagnation state 0.

[0145] Further, since the refrigerant passes through the inlet guide vane IGV and the diffuser VGD, which are both adiabatic processes, the enthalpy values at the inlet and outlet of the IGV and the VGD are equal, so:

[0146]

[0147]

[0148] wherein, represents the specific enthalpy of the superheated gas phase at the outlet of the inlet guide vane IGV in the refrigerant superheated gas state g and the stagnation state 0. represents the specific enthalpy of the superheated gas phase at the inlet of the inlet guide vane IGV in the refrigerant superheated gas state g and the stagnation state 0. represents the specific enthalpy of the superheated gas phase at the inlet of the diffuser VGD in the refrigerant superheated gas state g and the stagnation state 0. represents the specific enthalpy of the superheated gas phase at the outlet of the diffuser VGD in the refrigerant superheated gas state g and the stagnation state 0.

[0149] Therefore, the calculation formula of the system specific input shaft work can be further represented as:

[0150]

[0151] wherein, represents the system specific input shaft work, represents the specific enthalpy of the superheated gas phase at the outlet of the diffuser VGD in the refrigerant superheated gas state g and the stagnation state 0. represents the specific enthalpy of the saturated gas phase at the evaporator in the refrigerant saturated gas state gs.

[0152] In step S303 of some embodiments, specifically, the target system cooling efficiency refers to the system cooling performance coefficient during the actual cooling cycle. The target system cooling efficiency can be expressed as COPr (Coefficient of Performance), an index used to evaluate the ratio of cooling capacity to input power of the cooling system.

[0153] Specifically, the cooling energy efficiency of the target system can be calculated using the following formula:

[0154]

[0155] in, Indicates the cooling energy efficiency of the target system. Indicates the specific cooling capacity of the system. The system has more power than the input shaft.

[0156] Furthermore, since the system's specific cooling capacity and specific input shaft work have already been determined using the specific enthalpy of saturated liquid, saturated gas, and superheated gas, the formula for calculating the target system's cooling energy efficiency can be further expressed as:

[0157]

[0158] in, Indicates the cooling energy efficiency of the target system. This represents the refrigerant saturated gaseous state gs and the condensation saturation temperature. Enthalpy of saturated gaseous refrigerant per unit mass This indicates the temperature at which the refrigerant is saturated liquid (ls) and the condensation saturation temperature. Enthalpy of saturated liquid phase per unit mass of refrigerant express This represents the condensation saturation pressure (g) of the refrigerant in its superheated gaseous state. and compressed exhaust temperature The superheated gas has a higher enthalpy.

[0159] Through steps S301 to S303, the theoretical energy efficiency of the refrigeration system can be dynamically calculated using real-time physical property parameters (i.e., saturated liquid relative enthalpy, saturated gas relative enthalpy, and compression exhaust temperature). This avoids errors caused by equipment differences or performance degradation in fixed empirical models. Furthermore, by introducing the diffuser stagnation enthalpy, the energy state after the compressor actually does work is reflected more accurately, significantly improving the accuracy and reliability of the system's refrigeration energy efficiency calculation, thereby enhancing the accuracy of refrigeration performance prediction for the refrigeration system.

[0160] Please see Figure 4 In some embodiments, step S106 may include, but is not limited to, steps S401 to S403:

[0161] Step S401, obtain the performance characteristic model of the target chiller.

[0162] Step S402, during the running test operation of the target chiller, collect the unit input electric power and the unit measured rotating speed.

[0163] Step S403, substitute the unit input electric power and the unit measured rotating speed into the performance characteristic model to calculate the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency.

[0164] In step S401 of some embodiments, specifically, the performance characteristic model refers to a mathematical model describing the relationship between the efficiency of each key energy-consuming component (such as the frequency converter, the motor and the bearing transmission structure) in the target chiller and its operating parameters (such as the input power and the output rotating speed), and the performance characteristic model includes the frequency converter performance model, the motor performance model and the bearing transmission performance model.

[0165] In step S402 of some embodiments, specifically, the unit input electric power refers to the input electric power of the unit power distribution cabinet of the target chiller during the running test operation, the unit is kilowatt (kW), and the unit input electric power includes the frequency converter input power, the motor input power and the bearing transmission input power.

[0166] Specifically, the unit input electric power can be collected by the power meter installed on the power supply circuit of the target chiller.

[0167] Specifically, the unit measured rotating speed refers to the actual rotating speed of the target chiller during the running process, the unit is revolutions per minute (rpm), and the unit measured rotating speed includes the frequency converter measured rotating speed, the motor measured rotating speed and the bearing transmission measured rotating speed.

[0168] Specifically, the frequency converter measured rotating speed, the motor measured rotating speed and the bearing transmission measured rotating speed can be collected by the rotating speed sensor (such as Hall sensor, encoder) installed on the frequency converter shaft, the motor shaft end or the compressor shaft of the target chiller.

[0169] In step S403 of some embodiments, specifically, the frequency converter efficiency refers to the ratio of the output active power to the input active power in the process that the frequency converter converts the input power frequency alternating current into the variable frequency alternating current required by the compressor motor.

[0170] Specifically, the motor efficiency refers to the ratio of the output mechanical power to the input electric power in the process that the motor converts the input electric energy into the mechanical energy for driving the compressor.

[0171] Specifically, the bearing transmission efficiency refers to a ratio of an effective mechanical power transmitted to the compressor impeller to a mechanical power output by the motor in a process that the bearing and other transmission components in a power transmission system of the compressor transmit the mechanical power output by the motor to the compressor impeller.

[0172] Specifically, the inverter performance model, the motor performance model and the bearing transmission performance model can be expressed by the following formulas.

[0173] The inverter performance model is:

[0174] The motor performance model is:

[0175] The bearing transmission performance model is:

[0176] wherein, represents the inverter efficiency, represents the inverter input power, represents the inverter measured rotating speed, represents the motor efficiency, represents the motor input power, represents the motor measured rotating speed, represents the bearing transmission efficiency, represents the bearing transmission input power, represents the bearing transmission measured rotating speed. The inverter input power Win can also be considered as the power cabinet input power.

[0177] Further, the inverter input power Win and the inverter measured rotating speed Ninv are input into the inverter performance model to calculate the inverter efficiency; the inverter efficiency, the motor input power Wmot and the motor measured rotating speed Nmot are input into the motor performance model to calculate the motor efficiency; the inverter efficiency, the motor efficiency, the bearing transmission input power Wbt and the bearing transmission measured rotating speed Nbt are input into the bearing transmission performance model to calculate the bearing transmission efficiency.

[0178] Through the steps S401 to S403, the complex equipment and high cost required for directly testing the efficiencies of the inverter, the motor, the bearing and other components are effectively avoided, and the dynamic change characteristics of the efficiencies of different components under different working conditions are also considered to truly reflect the energy loss of the unit under the running test, thereby laying a solid foundation for accurately converting the theoretical refrigeration cycle performance into the actual operation performance of the unit, and improving the accuracy of the subsequent refrigeration performance prediction of the unit. ​​​​​​

[0179] Please see Figure 5 In some embodiments, step S106 may include, but is not limited to, steps S501 to S503:

[0180] Step S501: Obtain the mechanical structure characteristics of the target refrigerator, and determine the motor efficiency and bearing transmission efficiency of the target refrigerator based on the mechanical structure characteristics.

[0181] Step S502: Obtain the historical unit cooling energy efficiency and historical system cooling energy efficiency of the target chiller.

[0182] Step S503: Calculate the inverter efficiency based on historical unit cooling energy efficiency, historical system cooling energy efficiency, motor efficiency, and bearing transmission efficiency to obtain the inverter efficiency.

[0183] In step S501 of some embodiments, specifically, mechanical structural features refer to the physical components and inherent parameters related to the motor and bearing transmission in the target refrigerator, such as the motor model, rated power, design efficiency level, and the bearing type (such as rolling bearing, sliding bearing), lubrication method, and transmission connection form (such as direct coupling, gearbox), etc.

[0184] Specifically, since the motor efficiency changes relatively smoothly under different operating conditions, the data curve of the motor efficiency can be obtained by querying the manufacturer's data of the target refrigerator using the motor model and rated motor parameters to obtain a relatively fixed motor efficiency value.

[0185] Furthermore, the bearing transmission efficiency is mainly related to the bearing type, lubrication conditions, and temperature, but it does not vary much within the normal operating temperature range of the target refrigeration unit. Therefore, a relatively stable rated bearing transmission efficiency can usually be determined based on the mechanical structural characteristics of the bearing transmission.

[0186] For example, regarding motor efficiency, you can determine that the motor is a high-efficiency asynchronous motor with a rated efficiency of 95% by checking the motor nameplate. When the load rate does not change much, you can approximate this value of 95% to determine the motor efficiency. For standard rolling bearing drives, the transmission efficiency is usually stable in the range of 95%-99%, so you can determine the bearing transmission efficiency based on the actual needs by taking a value from the range.

[0187] In this embodiment, the motor efficiency and bearing transmission efficiency of the target refrigerator are determined based on the mechanical structure characteristics. By utilizing the relatively stable characteristics of motor and bearing efficiency, a relatively reliable motor efficiency and bearing transmission efficiency can be quickly obtained based on the inherent mechanical structure of the motor and bearing, avoiding the trouble of complex dynamic modeling due to the small changes in these two parameters.

[0188] In step S502 of some embodiments, specifically, the historical unit refrigeration energy efficiency refers to the actual refrigeration performance coefficient of the target refrigeration unit under a known working condition. The known working condition can be a standard working condition of the target refrigeration unit out of the factory, or a test working condition obtained by adding temporary test equipment.

[0189] Specifically, the historical system refrigeration energy efficiency refers to the actual system refrigeration performance coefficient of the refrigeration system under the known working condition of the target refrigeration unit.

[0190] Specifically, the historical unit refrigeration energy efficiency and the historical system refrigeration energy efficiency under the known working condition can be extracted from the historical operation records of the target refrigeration unit and the refrigeration performance energy efficiency test report.

[0191] In step S503 of some embodiments, specifically, the frequency converter efficiency can be determined by the following formula:

[0192]

[0193] wherein, represents the frequency converter efficiency, represents the historical system refrigeration energy efficiency, represents the motor efficiency, represents the bearing transmission efficiency, represents the historical unit refrigeration energy efficiency.

[0194] Further, the historical unit refrigeration energy efficiency can be determined by the following formula:

[0195]

[0196] wherein, represents the historical unit refrigeration capacity, in kW; represents the historical unit input electric power, in kW.

[0197] In this embodiment, the frequency converter efficiency is calculated based on the historical unit refrigeration energy efficiency, the historical system refrigeration energy efficiency, the motor efficiency, and the bearing transmission efficiency. In the case where the performance model of the frequency converter efficiency is difficult to construct, the historical unit refrigeration energy efficiency and the historical system refrigeration energy efficiency under the known working condition, and the known motor efficiency and bearing efficiency can be used to inversely deduce the frequency converter efficiency of the known working condition, so as to realize the prediction of the frequency converter efficiency under other similar unknown working conditions, and further improve the accuracy of the refrigeration performance prediction of the target refrigeration unit under different working conditions.

[0198] Through steps S501 to S503, the characteristics of the motor efficiency changing little and the bearing transmission efficiency being relatively stable are utilized, the variable frequency converter efficiency which changes greatly and is difficult to model is inversely calculated and determined by combining the historical unit refrigeration energy efficiency and the historical system refrigeration energy efficiency under the known working condition, the motor efficiency and the bearing efficiency are determined, the problem that the variable frequency converter efficiency is difficult to accurately obtain under the unknown working condition or the unknown variable frequency converter efficiency function is effectively solved, and reliable data basis is provided for subsequent unit refrigeration performance prediction of the target refrigeration machine.

[0199] Please refer to Figure 6 In some embodiments, step S106 can include, but is not limited to, steps S601 to S603.

[0200] Step S601, the target refrigeration performance model, the target system refrigeration energy efficiency, the variable frequency converter efficiency, the motor efficiency and the bearing transmission efficiency are used to perform effective energy efficiency calculation on the target refrigeration machine, and the unit refrigeration effective energy efficiency is obtained.

[0201] Step S602, the variable frequency converter efficiency, the motor efficiency and the bearing transmission efficiency are used to perform refrigeration loss calculation on the target refrigeration machine, and the unit refrigeration loss energy efficiency is obtained.

[0202] Step S603, the unit refrigeration effective energy efficiency and the unit refrigeration loss energy efficiency are used to perform refrigeration evaluation on the target refrigeration machine, and the unit refrigeration performance prediction data is obtained.

[0203] In step S601 of some embodiments, specifically, the pre-constructed target refrigeration performance model is an algorithm set integrating a refrigeration system cycle thermodynamic model, performance characteristic models of each component (variable frequency converter, motor, bearing), and whole machine energy efficiency calculation logic, and is used to predict the refrigeration performance of the target refrigeration machine.

[0204] Specifically, the unit refrigeration effective energy efficiency refers to the refrigeration efficiency that the target refrigeration machine can actually output after considering the energy loss of the variable frequency converter, the motor and the bearing transmission during the operation of the target refrigeration machine, and the unit refrigeration effective energy efficiency is usually in the form of performance coefficient COP.

[0205] Specifically, the target refrigeration performance model can be represented by the following formula:

[0206]

[0207] Wherein, The target unit refrigeration energy efficiency is represented by q, which represents the unit refrigeration capacity, and the unit is kJ / kg. The target unit refrigeration energy efficiency is represented by q, which represents the unit refrigeration capacity, and the unit is kJ / kg.

[0208] The target refrigeration performance model can also be represented by the following formula:

[0209]

[0210] wherein Q represents the refrigeration capacity of the unit, in kW; represents the input power of the unit cabinet, i.e., the input electric power of the unit, in kW.

[0211] Further, the input shaft power corresponding to the unit mass of refrigerant in the compressor of the refrigeration system can be represented as:

[0212]

[0213] wherein, represents the specific input shaft power of the system, represents the specific input electric power of the unit, represents the frequency converter efficiency, represents the motor efficiency, represents the bearing transmission efficiency.

[0214] Further, for the target refrigeration machine, the refrigerant is usually used to cool the motor and the bearing, consuming part of the evaporator refrigeration capacity, therefore, the target refrigeration performance model can be further represented as:

[0215]

[0216] wherein q represents the specific refrigeration capacity of the unit, represents the specific refrigeration capacity of the system, represents the specific input electric power of the unit, represents the frequency converter efficiency, represents the motor efficiency, represents the bearing transmission efficiency, and COP represents the refrigeration energy efficiency of the target unit.

[0217] Therefore, the target refrigeration performance model can be further represented as:

[0218]

[0219] wherein COP represents the refrigeration energy efficiency of the target unit, represents the refrigeration energy efficiency of the target system, represents the frequency converter efficiency, represents the motor efficiency, represents the bearing transmission efficiency.

[0220] Further, the refrigeration energy efficiency of the target system, the frequency converter efficiency, the motor efficiency, and the bearing transmission efficiency can be input into the target refrigeration performance model for multiplication operation, i.e., to obtain the refrigeration energy efficiency of the unit.

[0221] In step S602 of some embodiments, specifically, the unit refrigeration loss efficiency refers to the difference between the theoretical efficiency and the actual effective efficiency due to the energy conversion loss of the frequency converter, motor and bearing transmission and other components during the operation of the target refrigeration unit. The unit refrigeration loss efficiency is used to represent the degree of reduction of the overall efficiency of the target refrigeration unit under the comprehensive loss of the frequency converter, motor and bearing transmission.

[0222] Further, the frequency converter efficiency, motor efficiency and bearing transmission efficiency can be input to the target refrigeration performance model to calculate the component loss efficiency of the target refrigeration unit, i.e. to obtain the unit refrigeration loss efficiency.

[0223] Referring to Figure 7 In some embodiments, step S603 can include but is not limited to steps S701 to S702:

[0224] Step S701, according to the unit refrigeration effective efficiency and the unit refrigeration loss efficiency, the unit efficiency of the target refrigeration unit is predicted to obtain the target unit refrigeration efficiency.

[0225] Step S702, according to the target unit refrigeration efficiency and the unit input power, the refrigeration efficiency of the target refrigeration unit is evaluated to obtain the unit refrigeration performance prediction data.

[0226] In step S701 of some embodiments, specifically, the target unit refrigeration efficiency refers to the coefficient of performance COP of the target refrigeration unit under actual operating conditions, i.e. the refrigeration capacity generated by the input power of the target refrigeration unit.

[0227] Further, the target unit refrigeration efficiency can be obtained by subtracting the unit refrigeration loss efficiency from the unit refrigeration effective efficiency through the target refrigeration performance model.

[0228] In step S702 of some embodiments, specifically, the unit refrigeration performance prediction data refers to the predicted thermodynamic parameters of the target refrigeration unit in the refrigeration process, and the unit refrigeration performance prediction data includes the predicted unit refrigeration capacity. The unit refrigeration capacity refers to the overall unit output of the target refrigeration unit, and the unit is kW.

[0229] Specifically, the target unit refrigeration efficiency COP can be determined through the above calculation, and the unit input power of the target refrigeration unit is also collected , the unit is kW. The COP and are substituted into the following formula to determine the unit specific refrigeration capacity:

[0230] ;

[0231] wherein, represents the refrigeration capacity of the unit, represents the input electric power of the unit, COP represents the target unit refrigeration energy efficiency.

[0232] Through steps S701 to S702, the prediction process of first predicting the overall energy efficiency and then calculating the refrigeration capacity combined with the measured power fully considers the theoretical cycle performance of the target refrigeration machine and the actual operation loss. The final output prediction data not only contains the unit energy efficiency data COP, but also provides the unit refrigeration capacity value without the need for a flow meter, greatly improving the practical application value of refrigeration performance prediction and the efficiency of refrigeration performance prediction of the target refrigeration machine.

[0233] Through steps S601 to S603, the energy loss of each key component in the refrigeration system cycle and actual operation is comprehensively considered, which significantly improves the prediction accuracy of refrigeration performance.

[0234] In an optional embodiment of the present application, the specific values of the frequency converter efficiency, motor efficiency and bearing transmission efficiency can be determined based on the actual unit of the target refrigeration machine, which is not limited here.

[0235] For example, it can be determined that the frequency converter efficiency is only related to the input electric power of the unit within a certain frequency range, and the specific empirical formula of the frequency converter can be taken as:

[0236]

[0237] wherein, represents the frequency converter efficiency, represents the input electric power of the unit.

[0238] Further, if the motor efficiency is 95.0%, the bearing transmission efficiency is 95.0~99.5% (such as 97.3%), combined with the frequency converter efficiency , the target unit refrigeration energy efficiency COP of the target refrigeration machine can be determined only by measuring the evaporation saturation temperature, the condensation saturation temperature and the compressor discharge temperature.

[0239] The performance prediction method of the refrigeration machine provided in the application firstly acquires thermodynamic parameters reflecting the target refrigeration machine in the running test process by collecting the condensation saturation temperature of the condenser, the evaporation saturation temperature of the evaporator and the compression discharge temperature of the compressor in the running test operation process, replaces the traditional fixed factory curve parameters, and eliminates errors caused by equipment differences and performance changes from the source; secondly, the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy are calculated based on the condensation saturation temperature, the evaporation saturation temperature and the compression discharge temperature, the dynamic calculation of the thermophysical properties of the target refrigeration machine is realized, the defect that the fixed parameter curve is difficult to reflect the actual thermodynamic state of the target refrigeration machine is avoided, and the target system refrigeration energy efficiency of the refrigeration system is predicted according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy, so as to quantize the theoretical energy efficiency calculation of the refrigeration system cycle and improve the refrigeration performance prediction precision of the refrigeration system; further, the unit refrigeration loss of the target refrigeration machine is added to the refrigeration performance prediction process by acquiring the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, so as to accurately predict the refrigeration energy change of the target refrigeration machine in the actual operation; finally, the unit performance of the target refrigeration machine is predicted by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, so as to realize the actual refrigeration performance calculation from the refrigeration cycle theory to the refrigeration machine unit, effectively solve the refrigeration performance prediction deviation problem caused by ignoring the dynamic loss and the property change of the target refrigeration machine, significantly improve the refrigeration performance prediction precision of the target refrigeration machine, and thus improve the refrigeration performance prediction effect of the target refrigeration machine.

[0240] Please refer to Figure 8 The embodiment of the application further provides a refrigeration machine performance prediction device, a target refrigeration machine comprising a refrigeration system, the refrigeration system comprising an evaporator, a condenser and a compressor, which can realize the refrigeration machine performance prediction method, comprising:

[0241] The running test temperature acquisition module is used for performing a running test operation on the target refrigeration machine, and collecting the condensation saturation temperature of the condenser, the evaporation saturation temperature of the evaporator and the compression discharge temperature of the compressor in the running test operation process;

[0242] The saturated liquid phase specific enthalpy calculation module is used for calculating the liquid phase specific enthalpy of the condenser according to the condensation saturation temperature to obtain the saturated liquid phase specific enthalpy;

[0243] The saturated gas phase specific enthalpy calculation module is used for calculating the gas phase specific enthalpy of the evaporator according to the evaporation saturation temperature to obtain the saturated gas phase specific enthalpy;

[0244] a superheated gas phase specific enthalpy calculation module, configured to calculate a superheated gas phase specific enthalpy according to the compressed exhaust gas temperature and the condensation saturation pressure, and obtain the superheated gas phase specific enthalpy;

[0245] a system performance prediction module, configured to predict a refrigeration energy efficiency of the refrigeration system according to the saturated liquid phase specific enthalpy, the saturated gas phase specific enthalpy and the superheated gas phase specific enthalpy, and obtain a target system refrigeration energy efficiency;

[0246] an operation efficiency acquisition module, configured to acquire the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency;

[0247] a unit performance prediction module, configured to predict a unit performance of the target refrigeration machine by using the pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the frequency converter efficiency, the motor efficiency and the bearing transmission efficiency, and obtain unit refrigeration performance prediction data.

[0248] In a third aspect, an electronic device is provided, which includes a memory and a processor, the memory stores a computer program, and the processor implements the performance prediction method of the refrigeration machine according to any one of the embodiments of the first aspect of the present application when executing the computer program.

[0249] In a fourth aspect, a computer readable storage medium is provided, which stores a program, and the program is executed by a processor to implement the performance prediction method of the refrigeration machine according to any one of the embodiments of the first aspect of the present application.

[0250] Please refer to Figure 9 , Figure 9 The electronic device of another embodiment is illustrated, which includes:

[0251] The processor 901 can be implemented by a general-purpose CPU (Central Processing Unit), a microprocessor, an application specific integrated circuit (ASIC), or one or more integrated circuits, and is configured to execute related programs to implement the technical solutions provided by the embodiments of the present application.

[0252] The memory 902 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM), etc. The memory 902 can store an operating system and other application programs. When the technical solutions provided by the embodiments of the present application are implemented by software or firmware, the related program codes are stored in the memory 902 and are called and executed by the processor 901 to implement the performance prediction method of the refrigeration machine according to the embodiments of the present application.

[0253] The input / output interface 903 is configured to realize information input and output.

[0254] The communication interface 904 is configured to realize the communication interaction between the device and other devices. The communication can be realized by a wired manner (for example, a USB, a network cable, etc.) or a wireless manner (for example, a mobile network, WIFI, Bluetooth, etc.).

[0255] The bus 905 is configured to transmit information between the components (for example, the processor 901, the memory 902, the input / output interface 903, and the communication interface 904) of the device.

[0256] The processor 901, the memory 902, the input / output interface 903, and the communication interface 904 are connected to each other through the bus 905 to realize the communication connection between the components in the device.

[0257] The computer readable storage medium provided by the embodiments of the present application stores a computer program. When the computer program is executed by the processor, the performance prediction method of the refrigeration machine is realized.

[0258] The memory is a non-transitory computer readable storage medium, which can be used to store a non-transitory software program and a non-transitory computer executable program. In addition, the memory can include a high-speed random access memory and can also include a non-transitory memory, for example, at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory can optionally include a memory remotely arranged relative to the processor. These remote memories can be connected to the processor through a network. Examples of the network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0259] The embodiments described in the embodiments of the present application are used to more clearly illustrate the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions provided by the embodiments of the present application. Those skilled in the art can know that, with the evolution of technology and the appearance of new application scenarios, the technical solutions provided by the embodiments of the present application are also applicable to similar technical problems.

[0260] Those skilled in the art can understand that the technical solutions shown in the figures do not constitute a limitation to the embodiments of the present application, and can include more or fewer steps than the figures, or combine certain steps, or different steps.

[0261] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separated, that is, can be located in one place, or can be distributed to multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments.

[0262] Those skilled in the art can understand that all or some steps in the above disclosed method, functional modules / units in the system and device can be implemented as software, firmware, hardware and their appropriate combinations.

[0263] The terms "first", "second", "third", "fourth" and the like in the description of the present application and the above figures (if any) are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those clearly listed steps or units, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0264] It should be understood that in the present application, "at least one" means one or more, and "multiple" means two or more. "And / or" is used to describe the association between the associated objects, which means that there can be three relationships, for example, "A and / or B" can represent three cases: only A, only B, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects. "At least one of the following" or similar expressions means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0265] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented by other manners. For example, the apparatus embodiments described above are merely illustrative, for example, the division of the above units is merely a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or components shown or discussed can be indirect coupling or communication connection through some interfaces, apparatuses or units, and can be electrical, mechanical or other forms.

[0266] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they can be located in one place or distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0267] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0268] If the integrated unit is realized in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part of the prior art that makes a contribution or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method of each embodiment of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program storage media.

[0269] The preferred embodiments of the embodiments of the present application are described above with reference to the accompanying drawings, which are not limited to the scope of the embodiments of the present application. Any modifications, equivalent replacements and improvements made by those skilled in the art without departing from the scope and essence of the embodiments of the present application shall be within the scope of the embodiments of the present application.

Claims

1. A method for predicting the performance of a refrigeration machine, characterized in that, The target refrigerator includes a refrigeration system, which includes an evaporator, a condenser, and a compressor. The method includes: The target refrigeration unit is subjected to an operational test, and during the operational test, the condensation saturation temperature of the condenser, the evaporation saturation temperature of the evaporator, and the compression discharge temperature of the compressor are collected. The liquid phase enthalpy of the condenser is calculated based on the condensation saturation temperature to obtain the saturated liquid phase enthalpy. The enthalpy of the gas phase is calculated based on the evaporation saturation temperature to obtain the saturated gas phase enthalpy. The saturation pressure is calculated based on the condensation saturation temperature to obtain the condensation saturation pressure. The superheat specific enthalpy is calculated based on the compression exhaust temperature and the condensation saturation pressure to obtain the superheat specific enthalpy. The refrigeration efficiency of the refrigeration system is predicted based on the enthalpy of the saturated liquid, the enthalpy of the saturated gas, and the enthalpy of the superheated gas, to obtain the refrigeration efficiency of the target system. Obtain the inverter efficiency, motor efficiency, and bearing transmission efficiency; The unit performance of the target chiller is predicted by using a pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency, and the unit refrigeration performance prediction data is obtained. The step of predicting the refrigeration efficiency of the refrigeration system based on the enthalpy of the saturated liquid, the enthalpy of the saturated gas, and the enthalpy of the superheated gas, to obtain the target system's refrigeration efficiency, includes: The refrigeration capacity of the refrigeration system is calculated based on the enthalpy of the saturated gas and the enthalpy of the saturated liquid to obtain the specific refrigeration capacity of the system. The system shaft work of the refrigeration system is calculated based on the enthalpy of the superheated gas and the enthalpy of the saturated gas to obtain the specific input shaft work of the system. The cooling energy efficiency of the refrigeration system is evaluated based on the specific cooling capacity and the specific input shaft work of the system to obtain the target system cooling energy efficiency. The unit performance prediction of the target chiller is performed using a pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency, resulting in predicted unit refrigeration performance data, including: The effective energy efficiency of the target chiller is calculated using the target refrigeration performance model, the target system refrigeration energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency to obtain the unit's effective refrigeration energy efficiency. The cooling loss of the target chiller is calculated based on the inverter efficiency, the motor efficiency, and the bearing transmission efficiency to obtain the unit's cooling loss energy efficiency. The target chiller is evaluated based on the effective energy efficiency and energy loss efficiency of the chiller to obtain predicted data on the chiller's cooling performance.

2. The method according to claim 1, characterized in that, The acquisition of inverter efficiency, motor efficiency, and bearing transmission efficiency includes: Obtain the performance characteristic model of the target chiller; During the operation and testing of the target chiller, the unit input power and the measured unit speed of the target chiller are collected; The inverter efficiency, motor efficiency, and bearing transmission efficiency are obtained by substituting the unit's input power and measured speed into the performance characteristic model.

3. The method according to claim 1, characterized in that, The step of evaluating the target chiller based on the effective cooling efficiency and the cooling loss efficiency of the unit to obtain predicted cooling performance data for the unit includes: Based on the effective cooling energy efficiency and the cooling loss energy efficiency of the unit, the unit energy efficiency of the target chiller is predicted to obtain the target unit cooling energy efficiency. The cooling efficiency of the target chiller is evaluated based on the cooling energy efficiency of the target unit and the input electrical power of the unit, and the predicted cooling performance data of the unit is obtained.

4. The method according to claim 1, characterized in that, The step of calculating the superheated specific enthalpy based on the compressed exhaust temperature and the condensation saturation pressure to obtain the superheated gas specific enthalpy includes: Obtain the pressure enthalpy coefficient of the condensation saturation pressure, and perform pressure enthalpy fitting based on the pressure enthalpy coefficient and the condensation saturation pressure to obtain the pressure enthalpy; Obtain the pressure-temperature coupling coefficient between the condensation saturation pressure and the compressed exhaust temperature; The pressure-temperature coupling enthalpy is obtained by fitting the pressure-temperature specific enthalpy based on the pressure-temperature coupling coefficient, the condensation saturation pressure, and the compression exhaust temperature. The superheated gas specific enthalpy is obtained by summing the specific enthalpy based on the pressure specific enthalpy and the pressure-temperature coupled specific enthalpy.

5. The method according to any one of claims 1 to 4, characterized in that, The process of obtaining inverter efficiency, motor efficiency, and bearing transmission efficiency also includes: The mechanical structure characteristics of the target refrigerator are obtained, and based on the mechanical structure characteristics, the motor efficiency and bearing transmission efficiency of the target refrigerator are determined. Obtain the historical unit cooling energy efficiency and historical system cooling energy efficiency of the target chiller; The inverter efficiency is calculated based on the historical unit cooling efficiency, the historical system cooling efficiency, the motor efficiency, and the bearing transmission efficiency.

6. A performance prediction device for a refrigeration machine, characterized in that, The target refrigeration unit includes a refrigeration system, which includes an evaporator, a condenser, and a compressor, comprising: The test temperature acquisition module is used to perform a test operation on the target refrigerator and to acquire the condensing saturation temperature of the condenser, the evaporating saturation temperature of the evaporator, and the compression discharge temperature of the compressor during the test operation. The saturated liquid phase enthalpy calculation module is used to calculate the liquid phase enthalpy of the condenser based on the condensation saturation temperature, and obtain the saturated liquid phase enthalpy. The saturated gas phase enthalpy calculation module is used to calculate the gas phase enthalpy of the evaporator based on the evaporation saturation temperature, and obtain the saturated gas phase enthalpy. The superheated gas specific enthalpy calculation module is used to calculate the saturation pressure based on the condensation saturation temperature to obtain the condensation saturation pressure, and to calculate the superheated specific enthalpy based on the compression exhaust temperature and the condensation saturation pressure to obtain the superheated gas specific enthalpy. The system performance prediction module is used to predict the refrigeration energy efficiency of the refrigeration system based on the saturated liquid phase enthalpy, the saturated gas phase enthalpy, and the superheated gas phase enthalpy, and to obtain the target system refrigeration energy efficiency. The operating efficiency acquisition module is used to acquire inverter efficiency, motor efficiency, and bearing transmission efficiency. The unit performance prediction module is used to predict the unit performance of the target chiller using a pre-built target cooling performance model, the target system cooling energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency, and to obtain unit cooling performance prediction data. The step of predicting the refrigeration efficiency of the refrigeration system based on the enthalpy of the saturated liquid, the enthalpy of the saturated gas, and the enthalpy of the superheated gas, to obtain the target system's refrigeration efficiency, includes: The refrigeration capacity of the refrigeration system is calculated based on the enthalpy of the saturated gas and the enthalpy of the saturated liquid to obtain the specific refrigeration capacity of the system. The system shaft work of the refrigeration system is calculated based on the enthalpy of the superheated gas and the enthalpy of the saturated gas to obtain the specific input shaft work of the system. The cooling energy efficiency of the refrigeration system is evaluated based on the specific cooling capacity and the specific input shaft work of the system to obtain the target system cooling energy efficiency. The unit performance prediction of the target chiller is performed using a pre-constructed target refrigeration performance model, the target system refrigeration energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency, resulting in predicted unit refrigeration performance data, including: The effective energy efficiency of the target chiller is calculated using the target refrigeration performance model, the target system refrigeration energy efficiency, the inverter efficiency, the motor efficiency, and the bearing transmission efficiency to obtain the unit's effective refrigeration energy efficiency. The cooling loss of the target chiller is calculated based on the inverter efficiency, the motor efficiency, and the bearing transmission efficiency to obtain the unit's cooling loss energy efficiency. The target chiller is evaluated based on the effective energy efficiency and energy loss efficiency of the chiller to obtain predicted data on the chiller's cooling performance.

7. An electronic device, characterized in that, include: The system includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the performance prediction method for a refrigeration machine as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The storage medium stores a program that is executed by a processor to implement the performance prediction method for a refrigerator as described in any one of claims 1 to 5.

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