Electric power modeling method and system for air source heat pump

Abstract

The invention belongs to the technical field of network source coordination control, and discloses an electric power modeling method and system for an air source heat pump, and the method comprises the steps: analyzing the estimated power of a compressor at a rated frequency based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, and introducing a frequency conversion coefficient to correct the estimated power, outputting a power calculation model of the compressor; constructing an evaporator frosting additional power consumption model according to the air flow resistance increment generated by frosting and the power required by defrosting; according to the heating power of the air source heat pump and the efficiency of the rotating speed component, an auxiliary electric heating power calculation model and a warm lubricating oil viscosity loss model corresponding to the air source heat pump are constructed; and outputting an electric power modeling result of the air source heat pump by integrating the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model and the warm lubricating oil viscosity loss model. According to the invention, high-precision prediction of the heat pump electric power is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of network source coordination control, and particularly relates to an electric power modeling method and system for an air source heat pump. BACKGROUND

[0002] With the intensification of global warming, extreme low temperature events occur frequently, and traditional air source heat pumps face problems such as rapid evaporation temperature drop, rapid compression ratio increase, and exhaust temperature overrun, resulting in heating capacity attenuation and a significant decrease in the energy efficiency ratio (COP). However, the demand for clean heating is increasing, and high-efficiency heat pump technology is urgently needed to replace coal-fired boilers in extremely cold regions. However, the energy efficiency and stability of existing systems cannot meet the demand.

[0003] Traditional electric auxiliary heating consumes more than 50% of the power at -35℃, and it is necessary to optimize the frequency control and air supplement strategy through a precise power model to reduce operating costs. The emergence of new refrigerants and intelligent algorithms requires the model to be compatible with dynamic physical property parameters and multi-objective optimization functions. However, traditional heat pump power models are designed based on constant temperature conditions and do not fully consider the sudden change in refrigerant properties at ultra-low temperatures, the deterioration of dynamic frosting heat transfer, and the multi-stage cycle coupling effect. In addition, the optimization of the air supplement amount of the cascade compression relies on empirical parameters and lacks real-time modeling capability under dynamic conditions. Therefore, it is necessary to break through the energy efficiency bottleneck through a high-precision model.

[0004] Therefore, how to provide an electric power modeling method and system for an air source heat pump is a problem to be solved at present. SUMMARY

[0005] The embodiments of the present application provide an electric power modeling method and system for an air source heat pump to solve the problem of relying on empirical parameters and lacking real-time modeling capability under dynamic conditions in the prior art.

[0006] The following presents a simplified summary of some aspects of the disclosed embodiments in order to provide a basic understanding of such embodiments. This summary is not an extensive overview of the embodiments described in detail in the following detailed description, and is intended neither to identify key or critical elements nor to delineate the scope of such embodiments. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0007] According to a first aspect of the embodiments of the present application, an electric power modeling method for an air source heat pump is provided.

[0008] In one embodiment, the electric power modeling method for the air source heat pump comprises:

[0009] Based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, the estimated power of the compressor at the rated frequency is analyzed, and a frequency conversion coefficient is introduced to correct the estimated power, and a power calculation model of the compressor is outputted;

[0010] According to the air flow resistance increase amount and the defrosting power required by the frosting under the low temperature environment, an additional power consumption model of the evaporator frosting in the air source heat pump is constructed;

[0011] According to the heating power of the air source heat pump and the efficiency of the rotating speed component under the low temperature environment, an auxiliary electric heating power calculation model and a temperature lubricating oil viscous loss model corresponding to the air source heat pump are constructed;

[0012] The integrated power calculation model, the additional power consumption model of the evaporator frosting, the auxiliary electric heating power calculation model and the temperature lubricating oil viscous loss model output the modeling result of the electric power of the air source heat pump.

[0013] In one embodiment, based on the isentropic efficiency and the mechanical efficiency of the compressor in the air source heat pump, the estimated power of the compressor under the rated frequency is analyzed, and a frequency conversion coefficient is introduced to correct the estimated power, and the power calculation model of the compressor is output, including:

[0014] The evaporation and condensation pressure distribution in the air source heat pump is combined with the compressor volumetric efficiency to determine the refrigerant mass flow rate of the air source heat pump under low temperature and high temperature, and the specific enthalpy of the refrigerant at the outlet of the isentropic compression process under low temperature and high temperature conditions is analyzed respectively;

[0015] Based on the motor input power of the compressor during operation, the mechanical efficiency of the compressor is analyzed, and the isentropic efficiency of the compressor is obtained according to the ratio of the actual compression power of the compressor to the ideal isentropic compression power;

[0016] The refrigerant mass flow rate, the specific enthalpy of the refrigerant, the mechanical efficiency and the isentropic efficiency are integrated to calculate the estimated power of the compressor under high temperature and low temperature conditions respectively, and the linear relationship between the frequency of the compressor and the gas supply amount is analyzed;

[0017] Based on the linear relationship result, the power consumption correction coefficient corresponding to the rated frequency of the compressor frequency is determined, and after the estimated power is corrected by using the power consumption correction coefficient, the high temperature compressor power calculation model and the low temperature compressor power calculation model are output.

[0018] In one embodiment, according to the air flow resistance increase amount and the defrosting power required by the frosting under the low temperature environment, an additional power consumption model of the evaporator frosting in the air source heat pump is constructed, including:

[0019] The air flow resistance increase amount of the evaporator fin caused by the frosting under the low temperature environment is analyzed, and an evaporator fan power consumption increase calculation model in the air source heat pump is constructed by combining the air volume flow rate;

[0020] According to the power consumed by the compressor during defrosting and the single defrosting time, an defrosting power consumption calculation model is constructed by combining the evaporator fan power consumption increase during single defrosting;

[0021] The evaporator fan energy consumption increment calculation model is combined with the defrosting energy consumption calculation model to obtain an evaporator frosting additional power consumption model corresponding to the air source heat pump.

[0022] In one embodiment, the expression of the evaporator fan energy consumption increment calculation model is:

[0023]

[0024] The expression of the defrosting energy consumption calculation model is:

[0025] W defrost =(W comp,defrost +W fan,defrost )·t defrost ;

[0026] In the formula, W fan represents the evaporator fan energy consumption increment, δ represents the frost layer thickness, V air represents the air volume flow, η fan represents the comprehensive efficiency of the fan in converting electric energy into effective airflow kinetic energy, W defrost represents the defrosting energy consumption, W comp,defrost represents the power consumed by the compressor during the defrosting process, W fan,defrost represents the power consumed by the fan during the defrosting process, and t defrost represents the single defrosting time.

[0027] In one embodiment, according to the heating power of the air source heat pump and the efficiency of the rotating speed component in a low temperature environment, an auxiliary electric heating power calculation model and a warm lubricating oil viscous loss model corresponding to the air heat source pump are constructed, which include:

[0028] The air temperature in which the outdoor unit of the air heat source pump is located in a low temperature environment is analyzed, and the actual heating efficiency of the air heat source pump is analyzed according to the air temperature to determine the performance degradation of the air heat source pump;

[0029] Based on the electric heating conversion efficiency of the air heat source pump and the required heating power in a low temperature environment, an auxiliary electric heating power calculation model corresponding to the air heat source pump is constructed in combination with the actual heating efficiency.

[0030] The working efficiency of the compressor rotating speed component in the air heat source pump in a low temperature environment is obtained, the comprehensive mechanical efficiency of the compressor under standard working conditions is obtained, and the additional mechanical power loss caused by the increase of the lubricating oil viscous resistance in a low temperature environment is analyzed in combination with the rated power of the compressor to construct a warm lubricating oil viscous loss model.

[0031] In one embodiment, the expression of the auxiliary electric heating power calculation model is:

[0032] W aux =max(0,Qdemand Q heat (T amb ))·η aux ;

[0033] The expression of the warm lubricating oil viscous loss model is:

[0034]

[0035] In the formula, W aux represents the auxiliary electric heating power, Q demand represents the required heating power, Q heat (T amb ) represents the actual heating power of the air source heat pump at the ambient temperature T amb , η aux represents the electric heating conversion efficiency, ΔW oil represents the low-temperature lubricating oil viscous loss power increment, W comp represents the rated power of the compressor, η mech,low represents the working efficiency of the low-speed component of the compressor at low temperature, η mech,high represents the working efficiency of the high-speed component of the compressor at low temperature, and η mech,rated represents the comprehensive mechanical efficiency of the compressor under standard working conditions.

[0036] In an embodiment, the standard working conditions include corresponding states when the compressor is at normal temperature or without viscous loss, and the low-speed component of the compressor includes bearings and gears.

[0037] According to a second aspect of the embodiments of the present application, an electric power modeling system for an air source heat pump is provided.

[0038] In an embodiment, the electric power modeling system for the air source heat pump comprises:

[0039] A power calculation model construction unit is configured to analyze the estimated power of the compressor at the rated frequency based on the isentropic efficiency and the mechanical efficiency of the compressor in the air source heat pump, introduce a variable frequency coefficient to correct the estimated power, and output a power calculation model of the compressor.

[0040] An additional power consumption model construction unit is configured to construct an additional power consumption model of the evaporator frosting in the air source heat pump according to the air flow resistance increment caused by the frosting at low temperature and the power required for defrosting.

[0041] A power loss model construction unit is configured to construct an auxiliary electric heating power calculation model and a warm lubricating oil viscous loss model corresponding to the air heat source pump according to the heating power of the air source heat pump at low temperature and the efficiency of the rotating component.

[0042] The power modeling result output unit is configured to output the electric power modeling result of the air source heat pump by integrating the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model, and the warm lubricating oil viscous loss model.

[0043] In one embodiment, the power calculation model construction unit comprises:

[0044] The evaporation and condensation pressure distribution in the air source heat pump is combined with the compressor volumetric efficiency to determine the low-temperature and high-temperature refrigerant mass flow rates of the air source heat pump, and the specific enthalpy of the refrigerant at the outlet of the isentropic compression process under low-temperature and high-temperature conditions is analyzed, respectively.

[0045] Based on the motor input power of the compressor during operation, the mechanical efficiency of the compressor is analyzed, and the isentropic efficiency of the compressor is obtained according to the ratio of the actual compression power of the compressor to the ideal isentropic compression power.

[0046] The compressor estimated power under high-temperature and low-temperature conditions is calculated by integrating the refrigerant mass flow rate, the specific enthalpy of the refrigerant, the mechanical efficiency, and the isentropic efficiency, respectively, and the linear relationship between the compressor frequency and the gas delivery rate is analyzed.

[0047] Based on the linear relationship result, the power consumption correction coefficient corresponding to the compressor frequency and the rated frequency is determined, and after the estimated power is corrected by using the power consumption correction coefficient, the high-temperature compressor power calculation model and the low-temperature compressor power calculation model are output.

[0048] In one embodiment, the additional power consumption model construction unit comprises:

[0049] The increase in air flow resistance between the evaporator fins caused by frosting under low-temperature conditions is analyzed, and an evaporator fan power consumption increase calculation model in the air source heat pump is constructed by combining the air volume flow.

[0050] A defrosting power consumption calculation model is constructed according to the power consumed by the compressor during defrosting and the single defrosting time, combined with the evaporator fan power consumption increase during single defrosting.

[0051] The evaporator fan power consumption increase calculation model and the defrosting power consumption calculation model are combined to obtain the evaporator frosting additional power consumption model corresponding to the air source heat pump.

[0052] In one embodiment, the expression of the evaporator fan power consumption increase calculation model is:

[0053]

[0054] The expression of the defrosting power consumption calculation model is:

[0055] W defrost =(W comp,defrost +Wfan,defrost )·t defrost ;

[0056] In the formula, W fan represents the energy consumption increment of the evaporator fan, δ represents the frost thickness, V air represents the air volume flow, η fan represents the comprehensive efficiency of the fan in converting electric energy into effective airflow kinetic energy, W defrost represents the defrosting energy consumption, W comp,defrost represents the power consumed by the compressor during the defrosting process, W fan,defrost represents the power consumed by the fan during the defrosting process, t defrost represents the single defrosting time.

[0057] In one embodiment, the power loss model construction unit comprises:

[0058] The air temperature of the outdoor unit of the air source heat pump in a low-temperature environment is analyzed, and the actual heating efficiency of the air source heat pump is analyzed according to the air temperature to determine the performance degradation of the air source heat pump;

[0059] Based on the electric heating conversion efficiency of the air source heat pump and the required heating power in a low-temperature environment, an auxiliary electric heating power calculation model corresponding to the air source heat pump is constructed in combination with the actual heating efficiency.

[0060] The working efficiency of the compressor speed component of the air source heat pump in a low-temperature environment is obtained, the comprehensive mechanical efficiency of the compressor under standard working conditions is obtained, and the additional mechanical power loss caused by the increase in the viscous resistance of the lubricating oil in a low-temperature environment is analyzed in combination with the rated power of the compressor to construct a warm lubricating oil viscous loss model.

[0061] In one embodiment, the expression of the auxiliary electric heating power calculation model is:

[0062] W aux = max (0, Q demand - Q heat (T amb ))·η aux ;

[0063] The expression of the warm lubricating oil viscous loss model is:

[0064]

[0065] In the formula, W aux represents the auxiliary electric heating power, Q demand represents the required heating power, Q heat (T amb ) represents the actual heating power of the air source heat pump at the ambient temperature T amb , and η auxrepresents the electric heat conversion efficiency, ΔW oil represents the low-temperature lubricating oil viscous loss power increment, W comp represents the compressor rated power, η mech,low represents the low-temperature compressor low-speed component working efficiency, η mech,high represents the low-temperature compressor high-speed component working efficiency, η mech,rated represents the compressor comprehensive mechanical efficiency under the standard working condition.

[0066] In one embodiment, the standard working condition includes a state corresponding to a case where the compressor is at normal temperature or without viscous loss, and the compressor low-speed component includes bearings and gears.

[0067] According to a third aspect of the embodiments of the present application, a computer device is provided.

[0068] In one embodiment, the computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0069] According to a fourth aspect of the embodiments of the present application, a computer readable storage medium is provided.

[0070] In one embodiment, the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the above method.

[0071] The technical solutions provided by the embodiments of the present application can include the following beneficial effects:

[0072] The present application outputs the air source heat pump electric power modeling result by integrating the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model, and the low-temperature lubricating oil viscous loss model, thereby completing the multi-stage compression power consumption separation, dynamic environment coupling correction, and loss refinement modeling, realizing high-precision prediction of the super-low-temperature heat pump electric power, and providing a theoretical tool for design and control of clean heating systems in extremely cold regions.

[0073] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0074] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present application and, together with the specification, serve to explain the principles of the present application.

[0075] Figure 1 is a flowchart of an air source heat pump electric power modeling method according to an exemplary embodiment;

[0076] Figure 2 is a schematic diagram of an air source heat pump electric power modeling system according to an example embodiment;

[0077] Figure 3 is a structural schematic diagram of a computer device according to an example embodiment;

[0078] Figure 4 is a schematic diagram of an air source heat pump electric power modeling method according to an example embodiment. DETAILED DESCRIPTION

[0079] The following description and drawings are illustrative of the specific embodiments herein and are not intended to limit the scope of the embodiments. Various aspects of the embodiments can be included or substituted into other embodiments. The scope of the embodiments encompasses the whole scope of the claims and all available equivalents of the claims. In this document, the terms "first", "second", etc. are used only to distinguish one element from another, and do not require or imply any actual relationship or order between the elements. In fact, the first element can also be referred to as the second element, and vice versa. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that a structure, device or apparatus including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such structure, device or apparatus. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the structure, device or apparatus including the element. Various embodiments are described in a progressive manner, each focusing on the differences from other embodiments, and the same or similar parts between various embodiments can be referred to each other.

[0080] The terms "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like in this document indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplification of the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In the description herein, unless otherwise specified and limited, the terms "mount", "connect", "connection" should be understood broadly, for example, it can be a mechanical connection or an electrical connection, it can be a communication between two elements inside, it can be a direct connection or an indirect connection through an intermediate medium, and the specific meaning of the above terms can be understood by those skilled in the art according to the specific circumstances.

[0081] In this document, the term "a plurality" means two or more, unless otherwise specified.

[0082] In this document, the character " / " means the relationship between the front and rear objects is "or". For example, A / B means: A or B.

[0083] In this document, the term "and / or" is a description of the relationship between objects, which means that there can be three relationships. For example, A and / or B means: A or B, or, A and B.

[0084] It should be understood that although each step in the flowchart is shown in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless otherwise specified in this document, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the figure can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

[0085] Each module in the device or system of the present application can be realized by software, hardware and their combination in whole or in part. The above modules can be embedded in or independent of the processor in the computer device in hardware form, or stored in the memory in the computer device in software form, so as to call and execute the operations corresponding to the above modules by the processor.

[0086] In the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0087] Figure 1 An embodiment of the air source heat pump electric power modeling method of the present application is shown.

[0088] In this optional embodiment, the air source heat pump electric power modeling method comprises:

[0089] Step S101, based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, the estimated power of the compressor at the rated frequency is analyzed, and the variable frequency coefficient is introduced to correct the estimated power, and the power calculation model of the compressor is output;

[0090] Step S102, according to the increase of air flow resistance caused by frosting in low temperature environment and the power required for defrosting, the additional power consumption model of the evaporator frosting in the air source heat pump is constructed;

[0091] Step S103, according to the heating power of the air source heat pump and the efficiency of the rotating speed component in the low temperature environment, the auxiliary electric heating power calculation model and the temperature lubricating oil viscous loss model corresponding to the air heat source pump are constructed;

[0092] Step S104, the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model and the temperature lubricating oil viscous loss model output the air source heat pump power modeling result.

[0093] In this optional embodiment, when the estimated power of the compressor in the air source heat pump is analyzed based on the isentropic efficiency and mechanical efficiency of the compressor, and the variable frequency coefficient is introduced to correct the estimated power, the power calculation model of the compressor is output, the evaporating and condensing pressure distribution in the air source heat pump and the compressor volumetric efficiency are combined to determine the air source heat pump in low temperature and high temperature refrigerant mass flow, and the specific enthalpy of the isentropic compression process outlet under low temperature and high temperature conditions is analyzed respectively; based on the motor input power of the compressor in the running process, the mechanical efficiency of the compressor is analyzed, and the isentropic efficiency of the compressor is obtained according to the ratio of the actual compression power of the compressor to the ideal isentropic compression power; the refrigerant mass flow, the specific enthalpy of the refrigerant, the mechanical efficiency and the isentropic efficiency are integrated to calculate the estimated power of the compressor under high temperature and low temperature conditions respectively, and the linear relationship between the compressor frequency and the gas volume is analyzed; based on the linear relationship result, the power consumption correction coefficient corresponding to the compressor frequency and the rated frequency is determined, and after the estimated power is corrected by using the power consumption correction coefficient, the high temperature compressor power calculation model and the low temperature compressor power calculation model are output.

[0094] In this optional embodiment, when the evaporator frosting additional power consumption model in the air source heat pump is constructed according to the increase of air flow resistance caused by frosting in low temperature environment and the power required for defrosting, the increase of air flow resistance between evaporator fins caused by frosting in low temperature environment is analyzed, and the evaporator fan power consumption increment calculation model in the air source heat pump is constructed combined with air volume flow; according to the power consumed by the compressor in the defrosting process and the single defrosting time, combined with the evaporator fan power consumption increment in single defrosting process, the defrosting power consumption calculation model is constructed; the evaporator fan power consumption increment calculation model and the defrosting power consumption calculation model are combined to obtain the evaporator frosting additional power consumption model corresponding to the air source heat pump.

[0095] In the optional embodiment, when the auxiliary electric heating power calculation model and the warm lubricating oil viscous loss model corresponding to the air heat source pump are constructed according to the heating power of the air source heat pump under low temperature environment and the efficiency of the rotating speed component, the air temperature in which the outdoor unit of the air heat source pump is located under low temperature environment can be analyzed, and the actual heating efficiency of the air heat source pump is analyzed according to the air temperature to determine the performance degradation of the air heat source pump; the auxiliary electric heating power calculation model corresponding to the air heat source pump is constructed based on the electric heating conversion efficiency of the air heat source pump and the heating power required under low temperature environment, combined with the actual heating efficiency; the working efficiency of the compressor rotating speed component in the air heat source pump under low temperature environment is obtained, the comprehensive mechanical efficiency of the compressor under standard working condition is obtained, and the additional mechanical power loss caused by the increase of the lubricating oil viscous resistance under low temperature environment is analyzed combined with the rated power of the compressor to construct the warm lubricating oil viscous loss model.

[0096] It needs to be explained that the expression of the electric power modeling in the air source heat pump electric power modeling method is:

[0097] W total = W comp,low + W comp,high + W fan + W aux + W defrost + ΔW oil ;

[0098] In the formula, W comp,low represents the low temperature compressor power, W comp,high represents the high temperature compressor power, W aux represents the auxiliary electric heating power, W fan represents the evaporator fan energy consumption increment, W defrost represents the defrosting energy consumption, ΔW oil represents the low temperature lubricating oil viscous loss power increment, W total represents the air source heat pump electric power.

[0099] The compression power calculation model includes two parts: the rated frequency compressor power model and the variable frequency correction parameter, and the rated frequency compressor power includes the low temperature compressor part and the high temperature compressor part:

[0100] W comp,rate = W comp,rate,low + W comp,rate,high ;

[0101] In the formula, W comp,rate represents the power of the compressor at rated frequency (50Hz), W comp,rate,low represents the power of the low temperature compressor at rated frequency (50Hz), and W comp,rate,highIndicates the power of the high-temperature compressor at the rated frequency (50Hz). The power of the high and low temperature compressors at the rated frequencies are as follows:

[0102]

[0103] Where m low 、m high Respectively represent the low / high temperature refrigerant mass flow rate (kg / s), which is determined by the evaporation / condensation pressure and the volumetric efficiency of the compressor; h out,isen Represents the refrigerant specific enthalpy at the outlet of the isentropic compression process (kJ / kg), h in Indicates the actual specific enthalpy of the refrigerant at the compressor inlet (kJ / kg), η isen It represents the isentropic efficiency of the compressor, which represents the ratio of the actual compression work to the ideal isentropic compression work, and reflects irreversible factors such as gas flow loss and leakage loss. mech It represents the mechanical efficiency of the compressor, which represents the ratio of the motor input power converted into gas compression work, including bearing friction, lubricating oil viscosity loss, etc.

[0104] The compressor frequency and gas output have a nonlinear relationship, so the frequency conversion coefficient k(f) needs to be introduced to correct the actual power:

[0105] W comp =k(f)·W comp,rate ,k(f)=a·f 2 +b·f+c;

[0106] Where W comp It represents the power of the multi-stage compressor after the frequency conversion characteristic correction, k(f) represents the power consumption correction coefficient of the compressor frequency (Hz) and the rated frequency, which means that during frequency conversion operation, the compressor power and frequency have a nonlinear relationship. a, b, and c represent the fitting coefficients, which reflect the nonlinearity of the compressor frequency conversion characteristic and need to be calibrated through experiments. W comp，rate Expressed as the power of the compressor at rated frequency (50Hz).

[0107] At the same time, the ultra-low temperature compensation mechanism in the auxiliary electric heating power calculation model: when the ambient temperature is lower than -25℃ or COP<1.8, the auxiliary electric heating is started:

[0108] W aux =max(0,Q demand -Q heat (T amb ))·η aux ;

[0109] Where W aux Indicates the auxiliary electric heating power, Q demandQ represents the required heating power (kW, the total heat required to maintain the indoor temperature, related to the building envelope insulation performance, indoor and outdoor temperature difference, ventilation volume, etc., which needs to be dynamically calibrated by combining local meteorological data through heat load calculation software), Q heat (T amb ) represents the actual heating power (kW) of the air source heat pump at the ambient temperature T amb , reflecting the performance attenuation of the heat pump under low temperature working conditions, related to the evaporator heat exchange efficiency, compressor compression ratio, and refrigerant properties, T amb represents the air temperature (℃) at which the heat pump outdoor unit is located, η aux represents the electric heating conversion efficiency (usually 0.95-0.98), the theoretical limit of electric heating wire or PTC material is 1, but due to line loss, heat loss, etc., the actual value is slightly lower than 1.

[0110] Evaporator frosting additional power consumption model, the model includes two parts of fan power consumption increment and defrosting energy consumption.

[0111] The expression of the evaporator fan power consumption increment calculation model is:

[0112]

[0113] ΔP air =0.12·δ 1.5 ;

[0114] In the formula, W fan represents the evaporator fan power consumption increment, δ represents the frost thickness, humidity-temperature-time model prediction, V air represents the air volume flow, the nominal air volume maintained by the fan, after frosting, the resistance increase needs to be compensated by increasing the speed or power, the air volume needs to be increased by 10%~20% during frosting, η fan represents the comprehensive efficiency of the fan converting electric energy into effective airflow kinetic energy, the direct drive efficiency is usually 0.95~0.98, the belt drive efficiency is 0.85~0.90, ΔP air represents the increase of air flow resistance between evaporator fins caused by frosting.

[0115] The expression of the defrosting energy consumption calculation model is:

[0116] W defrost =(W comp,defrost +W fan,defrost )·t defrost ;

[0117] In the formula, W defrost represents the total energy consumed to complete one defrosting operation, W comp,defrostPd represents the power consumed by the compressor during the defrosting process. In scenarios such as hot gas defrosting or hot gas bypass defrosting, the compressor needs to do extra work to provide high-temperature refrigerant to melt the frost layer. This power is usually higher than the normal heating / cooling mode. The power is related to the type of refrigerant, system pressure, and frost thickness. Generally, it is 1.2-1.5 times the rated power, W fan,defrost Pf represents the power consumed by the fan during the defrosting process. The fan needs to remain running to assist in heat distribution, t defrost Td represents the single defrosting time, which is positively related to the latent heat required for frost melting.

[0118] The expression of the warm lubricating oil viscous loss model is:

[0119]

[0120] In the formula, ΔW oil ΔW represents the low-temperature lubricating oil viscous loss power increment, representing the additional mechanical power loss due to the increase in lubricating oil viscous resistance in low-temperature environments, W comp Pd represents the rated power of the compressor, η mech,low η represents the efficiency of low-speed components such as bearings and gears in the mechanical system at low temperatures, η mech,high η represents the efficiency of high-speed components such as motor rotors at low temperatures, η mech,rated η represents the comprehensive mechanical efficiency of the compressor under standard working conditions (normal temperature or without viscous loss), reflecting the energy conversion capacity of the compressor under ideal conditions. The formula uses it as a benchmark value to compare the difference in low-temperature efficiency. Generally, it is 0.90-0.95. Three-axis vibration sensor arrays are arranged at the compressor exhaust port to collect three-dimensional vibration signals. The vibration pulses are converted into space-time codes and extracted through SNN network for time-frequency coupling feature extraction, realizing dynamic correction of efficiency parameters.

[0121] In this alternative embodiment, the air source heat pump system building heat load 5000m 2 Residential, unit heat load 80W / m 2 , total demand 400kW, ambient temperature -26.4℃, relative humidity 75%, operating cycle 24 hours continuous operation, single defrosting cycle 90 minutes (defrosting 10 minutes, heating 80 minutes) actual total power consumption 3550kWh / day, average power 147.9kW, the air source heat pump power modeling method includes the following steps:

[0122] (1) The power of the two-stage compression of the cascade type is

[0123] At -26.4℃, the mass flow rate m low =0.5kg / s, the enthalpy difference Δh low =150KJ / kg, and the isentropic efficiency η isen,low= 0.78, mechanical efficiency η mech,low = 0.85, mass flow rate m in high-temperature stage compressor high = 0.3 kg / s, enthalpy difference Δh high = 120 KJ / kg, isentropic efficiency η isen,high = 0.82, mechanical efficiency η mech,high = 0.88, then:

[0124]

[0125] The total compression power is 114.7 + 52.3 = 167.0 KW.

[0126] (2) Frequency correction

[0127] After frequency optimization, the COP is increased from 2.03 to 2.10, and the correction coefficient is:

[0128]

[0129] After correction, the compression power: 167.0 x 1.034 ≈ 172.7 KW.

[0130] (3) Auxiliary electric heating power

[0131] The actual heat pump heating capacity: Q heat = 8.5 kW x 10 units = 85 kW;

[0132] W aux = max(0, 400-85) x 0.95 = 299.3 kW.

[0133] (4) Frost additional power consumption

[0134] The actual frost causes the fan power to increase by 20%, and the single defrost energy consumption is 0.8 kWh, so the initial fan power W fan = 5 kW, after frosting 5 x 1.2 = 6 kW, defrosting energy consumption is 16 times defrosting per day, total power consumption 0.8 x 16 = 12.8 kWh, total additional power consumption: (6-5) x 24 + 12.8 = 36.8 kW.

[0135] (5) Lubricating oil viscous loss

[0136] The mechanical efficiency is reduced from the rated 0.93 to 0.85, then ΔW oil = 167.0 x (1 / 0.85-1 / 0.93) ≈ 3.2 kW, the total power prediction, W total = 172.7 + 299.3 + 36.8 + 3.2 ≈ 512.0 kW.

[0137] While the traditional model only considers the compression power and static COP: compression power, directly using rated COP = 2.03, without frequency conversion correction, then W comp = 400 / 2.03 ≈ 197.0 kW;

[0138] Auxiliary heating, according to the heat load gap 100%:

[0139] W aux = (400-85) * 0.95 ≈ 299.3 kW, the total power prediction is 197.0 + 299.3 = 496.3 kW.

[0140] As shown in Table 1, the comparison results of the present example and the traditional modeling show that the modeling method proposed in the embodiment realizes high-precision prediction of the electric power of the super-low-temperature heat pump through multi-stage compression separation, dynamic environment correction and loss refined modeling.

[0141] Table 1: Comparison results of the present example and the traditional modeling

[0142] Parameters New model prediction Traditional model prediction Measured value Total power (kW) 512.0 512.0 509.5 COP 2.10 2.03 2.15 Frosting energy consumption ratio 7.2％ 0％ 7.5％ Lubricating oil consumption ratio 0.6％ 0％ 0.7％

[0143] Figure 2 An embodiment of the electric power modeling system for air source heat pump of the present application is shown.

[0144] In this alternative embodiment, the electric power modeling system for air source heat pump comprises:

[0145] The power calculation model construction unit 201 is configured to analyze the estimated power of the compressor at the rated frequency based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, and introduce a frequency conversion coefficient to correct the estimated power, and output a power calculation model of the compressor.

[0146] The additional power consumption model construction unit 202 is configured to construct an evaporator frosting additional power consumption model in the air source heat pump according to the increase in air flow resistance caused by frosting in low temperature environment and the power required for defrosting.

[0147] The power loss model construction unit 203 is configured to construct an auxiliary electric heating power calculation model and a warm lubricating oil viscous loss model corresponding to the air heat source pump according to the heating power of the air source heat pump in low temperature environment and the efficiency of the rotating speed component.

[0148] The power modeling result output unit 204 is configured to output the electric power modeling result of the air source heat pump by integrating the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model and the warm lubricating oil viscous loss model.

[0149] In this alternative embodiment, the power calculation model construction unit 201 comprises:

[0150] The evaporation and condensation pressure distribution in the air source heat pump is combined with the compressor volume efficiency to determine the low-temperature and high-temperature refrigerant mass flow rates of the air source heat pump, and the specific enthalpy of the refrigerant at the outlet of the isentropic compression process under low-temperature and high-temperature conditions is analyzed respectively;

[0151] Based on the motor input power of the compressor during operation, the mechanical efficiency of the compressor is analyzed, and the isentropic efficiency of the compressor is obtained according to the ratio of the actual compression power of the compressor to the ideal isentropic compression power.

[0152] The estimated power of the compressor under high-temperature and low-temperature conditions is calculated by integrating the refrigerant mass flow rate, the specific enthalpy of the refrigerant, the mechanical efficiency, and the isentropic efficiency, and the linear relationship between the frequency of the compressor and the gas transmission amount is analyzed.

[0153] Based on the linear relationship result, the power consumption correction coefficient corresponding to the frequency and the rated frequency of the compressor is determined, and after the estimated power is corrected by using the power consumption correction coefficient, the high-temperature compressor power calculation model and the low-temperature compressor power calculation model are output.

[0154] In this optional embodiment, the additional power consumption model construction unit 202 includes:

[0155] The increase in air flow resistance between the evaporator fins caused by frosting in a low-temperature environment is analyzed, and an evaporator fan power consumption increase calculation model in the air source heat pump is constructed by combining the air volume flow rate.

[0156] According to the power consumed by the compressor during defrosting and the single defrosting time, and combining the evaporator fan power consumption increase during single defrosting, a defrosting power consumption calculation model is constructed.

[0157] The evaporator fan power consumption increase calculation model and the defrosting power consumption calculation model are combined to obtain the evaporator frosting additional power consumption model corresponding to the air source heat pump.

[0158] In one embodiment, the power loss model construction unit 203 includes:

[0159] The air temperature in which the outdoor unit of the air source heat pump is located in a low-temperature environment is analyzed, and the actual heating efficiency of the air source heat pump is analyzed according to the air temperature to determine the performance degradation of the air source heat pump.

[0160] Based on the electric heating conversion efficiency of the air source heat pump and the required heating power in a low-temperature environment, an auxiliary electric heating power calculation model corresponding to the air source heat pump is constructed by combining the actual heating efficiency.

[0161] The working efficiency of a compressor rotating speed component in an air heat source pump under a low temperature environment is acquired, the comprehensive mechanical efficiency of the compressor under a standard working condition is acquired, and the additional mechanical power loss caused by the increase of lubricating oil viscous resistance under the low temperature environment is analyzed by combining with the rated power of the compressor to construct a lubricating oil viscous loss model.

[0162] In one embodiment, a computer device, which can be a server, has an internal structure diagram as shown in Figure 3 The computer device includes a processor, a memory and a network interface connected through a system bus. The processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for running the operating system and the computer program in the non-volatile storage medium. The database of the computer device is configured to store static information and dynamic information data. The network interface of the computer device is configured to communicate with an external terminal through a network connection. The computer program is executed by the processor to implement the steps in the above method embodiments.

[0163] Those skilled in the art can understand that Figure 3 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0164] In addition, the present application also provides a computer device including a memory and a processor, the memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0165] In addition, the present application also provides a computer readable storage medium having a computer program stored thereon, and the computer program is executed by the processor to implement the steps in the above method embodiments.

[0166] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the processes of the above-mentioned embodiments. Any reference to memory, storage, database or other medium used in each embodiment of the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0167] The present application is not limited to the structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present application is only limited by the appended claims.

Claims

1. A method for modeling the electrical power consumption of an air source heat pump, characterized in that: The modeling approach includes: Based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, the estimated power of the compressor at the rated frequency is analyzed, and the frequency conversion coefficient is introduced to correct the estimated power, and the power calculation model of the compressor is output; Based on the increase in air flow resistance caused by frosting and the power required for defrosting, a frosting additional power consumption model for the evaporator in an air source heat pump is constructed. According to the heating power and speed efficiency of the air source heat pump, the auxiliary electric heating power calculation model and warm lubricating oil viscous loss model corresponding to the air source heat pump are constructed; The integrated power calculation model, evaporator frosting additional power consumption model, auxiliary electric heating power calculation model and warm lubricating oil viscous loss model output the air source heat pump electrical power modeling results.

2. The air source heat pump power modeling method according to claim 1, characterized in that: The isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump are analyzed to estimate the power of the compressor at the rated frequency, and the frequency conversion coefficient is introduced to correct the estimated power. The power calculation model of the output compressor includes: The evaporation and condensation pressure distributions in the air source heat pump are combined with the compressor volumetric efficiency to determine the refrigerant mass flow rate under different temperature conditions of the air source heat pump, and the refrigerant specific enthalpy at the outlet of the isentropic compression process under different temperature conditions is analyzed respectively; The mechanical efficiency of the compressor is analyzed based on the motor input power during the operation of the compressor. At the same time, the isentropic efficiency of the compressor is obtained based on the ratio of the actual compression power of the compressor to the ideal isentropic compression power. The estimated compressor power under different temperature conditions is calculated by integrating refrigerant mass flow, refrigerant specific enthalpy, mechanical efficiency and isentropic efficiency, and the linear relationship between compressor frequency and gas output is analyzed. Based on the linear relationship results, the power consumption correction coefficient corresponding to the compressor frequency and the rated frequency is determined, and after the estimated power is corrected using the power consumption correction coefficient, the high-temperature compressor power calculation model and the low-temperature compressor power calculation model are output.

3. The air source heat pump power modeling method according to claim 1, characterized in that: The construction of the additional power consumption model for evaporator frosting in the air source heat pump based on the increase in air flow resistance caused by frosting and the power required for defrosting includes: Analyze the frost layer thickness to analyze the increase in air flow resistance between the evaporator fins caused by frost, and build a calculation model for the energy consumption increment of the evaporator fan in the air source heat pump based on the air volume flow rate; Based on the power consumed by the compressor during the defrost process and the single defrost time, combined with the energy consumption increment of the evaporator fan during a single defrost process, a defrost energy consumption calculation model is constructed. The evaporator fan energy consumption increment calculation model is combined with the defrost energy consumption calculation model to obtain the evaporator frosting additional power consumption model corresponding to the air source heat pump.

4. The air source heat pump power modeling method according to claim 3 is characterized in that: The expression of the evaporator fan energy consumption increment calculation model is: The expression of the defrost energy consumption calculation model is: W defrost =(W comp,defrost +W fan,defrost )·t defrost ; Where W fan represents the energy consumption increment of the evaporator fan, δ represents the thickness of the frost layer, V air represents the air volume flow rate, η fan It represents the comprehensive efficiency of the fan in converting electrical energy into effective airflow kinetic energy, W defrost Indicates defrost energy consumption, W comp,defrost Indicates the power consumed by the compressor during the defrosting process, W fan,defrost Indicates the power consumed by the fan during the defrosting process, t defrost Indicates single defrost time.

5. The air source heat pump power modeling method according to claim 1, characterized in that: The auxiliary electric heating power calculation model and warm lubricating oil viscous loss model corresponding to the air source heat pump are constructed based on the heating power and speed component efficiency of the air source heat pump, including: Analyze the air temperature of the outdoor unit of the air heat source pump, and analyze the actual heating efficiency of the air heat source pump based on the air temperature to determine the performance attenuation of the air heat source pump; Based on the electric-to-heat conversion efficiency and heating power of the air heat source pump and combined with the actual heating efficiency, a calculation model for the auxiliary electric heating power corresponding to the air heat source pump is constructed; The working efficiency of the compressor speed components in the air heat source pump is obtained, and the comprehensive mechanical efficiency of the compressor under standard operating conditions is obtained. The additional mechanical power loss caused by the increase in lubricating oil viscous resistance is analyzed in combination with the rated power of the compressor, and a warm lubricating oil viscous loss model is constructed.

6. The air source heat pump power modeling method according to claim 5, characterized in that: The expression of the auxiliary electric heating power calculation model is: W aux =max(0,Q demand -Q heat (T amb ))·η aux ; The expression of the warm lubricating oil viscous loss model is: Where W aux Indicates the auxiliary electric heating power, Q demand Indicates the required heating power, Q heat (T amb ) represents the air source heat pump at ambient temperature T amb The actual heating power under aux Indicates the electrothermal conversion efficiency, ΔW oil Indicates the increase in lubricating oil viscous loss power, W comp Indicates the rated power of the compressor, η mech,low Indicates the working efficiency of the low-speed components of the compressor, η mech,high Indicates the working efficiency of the high-speed components of the compressor, η mech,rated Indicates the comprehensive mechanical efficiency of the compressor under standard operating conditions.

7. The air source heat pump power modeling method according to claim 6, characterized in that: The standard operating condition includes a state corresponding to when the compressor is at room temperature or has no viscous loss, and the low-speed components of the compressor include bearings and gears.

8. An air source heat pump power modeling system, characterized in that: The modeling system includes: A power calculation model building unit is used to analyze the estimated power of the compressor at the rated frequency based on the isentropic efficiency and mechanical efficiency of the compressor in the air source heat pump, introduce the frequency conversion coefficient to correct the estimated power, and output the power calculation model of the compressor; An additional power consumption model building unit is used to build an additional power consumption model for frosting of the evaporator in the air source heat pump according to the increase in air flow resistance caused by frosting and the power required for defrosting; The power loss model construction unit is used to construct the auxiliary electric heating power calculation model and the warm lubricating oil viscous loss model corresponding to the air source heat pump according to the heating power and speed component efficiency of the air source heat pump; The power modeling result output unit is used to integrate the power calculation model, the evaporator frosting additional power consumption model, the auxiliary electric heating power calculation model and the warm lubricating oil viscous loss model to output the air source heat pump electric power modeling results.

9. The air source heat pump power modeling system according to claim 8, characterized in that: The power calculation model building unit includes: The evaporation and condensation pressure distributions in the air source heat pump are combined with the compressor volumetric efficiency to determine the refrigerant mass flow rate under different temperature conditions of the air source heat pump, and the refrigerant specific enthalpy at the outlet of the isentropic compression process under different temperature conditions is analyzed respectively; The mechanical efficiency of the compressor is analyzed based on the motor input power during the operation of the compressor. At the same time, the isentropic efficiency of the compressor is obtained based on the ratio of the actual compression power of the compressor to the ideal isentropic compression power. The estimated compressor power under different temperature conditions is calculated by integrating refrigerant mass flow, refrigerant specific enthalpy, mechanical efficiency and isentropic efficiency, and the linear relationship between compressor frequency and gas output is analyzed. Based on the linear relationship results, the power consumption correction coefficient corresponding to the compressor frequency and the rated frequency is determined, and after the estimated power is corrected using the power consumption correction coefficient, the high-temperature compressor power calculation model and the low-temperature compressor power calculation model are output.

10. The air source heat pump power modeling system according to claim 8, characterized in that: The additional power consumption model building unit includes: Analyze the frost layer thickness to analyze the increase in air flow resistance between the evaporator fins caused by frost, and build a calculation model for the energy consumption increment of the evaporator fan in the air source heat pump based on the air volume flow rate; Based on the power consumed by the compressor during the defrost process and the single defrost time, combined with the energy consumption increment of the evaporator fan during a single defrost process, a defrost energy consumption calculation model is constructed. The evaporator fan energy consumption increment calculation model is combined with the defrost energy consumption calculation model to obtain the evaporator frosting additional power consumption model corresponding to the air source heat pump.

11. The air source heat pump power modeling system according to claim 10, characterized in that: The expression of the evaporator fan energy consumption increment calculation model is: The expression of the defrost energy consumption calculation model is: W defrost =(W comp,defrost +W fan,defrost )·t defrost ; Where W fan represents the energy consumption increment of the evaporator fan, δ represents the thickness of the frost layer, V air represents the air volume flow rate, η fan It represents the comprehensive efficiency of the fan in converting electrical energy into effective airflow kinetic energy, W defrost Indicates defrost energy consumption, W comp,defrost Indicates the power consumed by the compressor during the defrosting process, W fan,defrost Indicates the power consumed by the fan during the defrosting process, t defrost Indicates single defrost time.

12. The air source heat pump power modeling system according to claim 8, characterized in that: The power loss model building unit includes: Analyze the air temperature of the outdoor unit of the air heat source pump, and analyze the actual heating efficiency of the air heat source pump based on the air temperature to determine the performance attenuation of the air heat source pump; Based on the electric-to-heat conversion efficiency and heating power of the air heat source pump and combined with the actual heating efficiency, a calculation model for the auxiliary electric heating power corresponding to the air heat source pump is constructed; The working efficiency of the compressor speed components in the air heat source pump is obtained, and the comprehensive mechanical efficiency of the compressor under standard operating conditions is obtained. The additional mechanical power loss caused by the increase in lubricating oil viscous resistance is analyzed in combination with the rated power of the compressor, and a warm lubricating oil viscous loss model is constructed.

13. The air source heat pump power modeling system according to claim 12, characterized in that: The expression of the auxiliary electric heating power calculation model is: W aux =max(0,Q demand -Q heat (T amb ))·η aux ; The expression of the warm lubricating oil viscous loss model is: Where W aux Indicates the auxiliary electric heating power, Q demand Indicates the required heating power, Q heat (T amb ) represents the air source heat pump at ambient temperature T amb The actual heating power under aux Indicates the electrothermal conversion efficiency, ΔW oil Indicates the increase in lubricating oil viscous loss power, W comp Indicates the rated power of the compressor, η mech,low Indicates the working efficiency of the low-speed components of the compressor, η mech,high Indicates the working efficiency of the high-speed components of the compressor, η mech,rated Indicates the comprehensive mechanical efficiency of the compressor under standard operating conditions.

14. The air source heat pump power modeling system according to claim 13, characterized in that: The standard operating condition includes a state corresponding to when the compressor is at room temperature or has no viscous loss, and the low-speed components of the compressor include bearings and gears.

15. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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