A variable frequency air conditioner performance dynamic test system based on air enthalpy difference method

Abstract

This invention relates to the field of air conditioning performance testing technology, and specifically to a dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method. The system includes an environmental condition simulation module, an operating parameter acquisition module, a performance index evaluation module, and a performance qualification determination module. The environmental condition simulation module provides the variable frequency air conditioner under test with different temperature and humidity combinations, effectively improving the representativeness and comprehensiveness of the test. The operating parameter acquisition module collects air enthalpy difference-related parameters under different environmental conditions in real time. The performance index evaluation module evaluates performance indicators from three aspects: energy efficiency, stability, and frequency conversion response. The performance qualification determination module determines the performance qualification of the variable frequency air conditioner based on the collaborative analysis of multi-dimensional indicators. Through the comprehensive determination of multi-dimensional indicators, a comprehensive evaluation of the overall performance of the variable frequency air conditioner is achieved, ensuring the consistency between test results and actual user experience, and improving the rigor and accuracy of air conditioning quality control.

Description

Technical Field

[0001] This invention relates to the field of air conditioning performance testing technology, and specifically to a dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method. Background Technology

[0002] With the continued advancement of energy conservation and emission reduction policies, inverter air conditioners have become the mainstream in the market due to their advantages such as high energy efficiency, rapid temperature adjustment, and stable operation. However, the performance of inverter air conditioners is affected by multiple factors such as changes in ambient temperature and humidity and switching of operating conditions. Traditional steady-state enthalpy difference testing methods can no longer fully reflect their dynamic performance in actual operation. Therefore, there is an urgent need for a system that can comprehensively test the energy efficiency, stability, and inverter response capability of inverter air conditioners under dynamic environmental conditions.

[0003] Existing technologies, such as Chinese Patent Publication No. CN120313157A, disclose an air conditioner energy efficiency testing system and a control method for an air conditioner efficiency testing platform. This invention, based on dynamic temperature control technology, dynamically adjusts the dry-bulb / wet-bulb temperature of the air in the test room. It obtains real-time heat load through a building heat load prediction simulator and calculates dynamic temperature and humidity changes using an indoor temperature and humidity prediction simulator. This solution solves the problem that traditional enthalpy difference method test benches cannot reflect the dynamic operating performance of air conditioners, providing fundamental technical support for dynamic testing of air conditioners.

[0004] However, existing technologies have the following problems: 1. Although existing technologies can dynamically adjust the ambient temperature, they do not conduct detailed evaluations of the energy efficiency of variable frequency air conditioners under different operating conditions. Judging the overall energy efficiency alone cannot accurately reflect the energy-saving characteristics of air conditioners in different environments, which may lead to misjudgment or underestimation of the energy efficiency advantages of variable frequency air conditioners.

[0005] 2. Existing technologies do not integrate multiple indicators such as energy efficiency, stability, and frequency response to determine performance qualification. They rely solely on the evaluation results of a single dimension. A single standard cannot fully reflect the comprehensive performance of variable frequency air conditioners, which may lead to the masking of some performance defects and affect the overall control of product quality. Summary of the Invention

[0006] To address the aforementioned problems in existing technologies, this invention provides a dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method. Through modular design and multi-dimensional index fusion analysis, it achieves a comprehensive evaluation and qualification determination of the dynamic performance of variable frequency air conditioners.

[0007] The technical solution adopted by the present invention to solve its technical problem is: a dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method, including an environmental condition simulation module, an operating parameter acquisition module, a performance index evaluation module, and a performance qualification judgment module.

[0008] The connections between the modules are as follows: the environmental condition simulation module is connected to the operating parameter acquisition module; the operating parameter acquisition module is connected to the performance index evaluation module; and the performance qualification judgment module is connected to the performance index evaluation module.

[0009] The environmental condition simulation module sets up an environmental test simulation chamber with programmable temperature and humidity to provide different temperature and humidity combinations for the variable frequency air conditioner under test.

[0010] The operation parameter acquisition module collects real-time air enthalpy difference related parameters of the variable frequency air conditioner under different environmental conditions.

[0011] The performance evaluation module includes an energy efficiency performance evaluation unit, a stability performance evaluation unit, and a frequency conversion response performance evaluation unit. The energy efficiency performance evaluation unit integrates and analyzes the air conditioner's output energy based on the correlation parameters of air enthalpy difference under different environmental conditions, and evaluates the energy efficiency performance indicators based on the air conditioner's output energy.

[0012] The stability performance evaluation unit constructs an output energy dynamic curve based on the dynamic sequence of air conditioner output energy during continuous operation under different environmental conditions, and evaluates the stability performance index by the deviation of the curve from the reference energy dynamic curve.

[0013] The frequency converter response performance evaluation unit extracts the response delay time, start-up speed and transient energy efficiency ratio during the period of cross-environmental operating condition change based on the output energy dynamic curves corresponding to different environmental operating conditions, and evaluates the frequency converter response performance indicators in combination with preset standard values.

[0014] The performance qualification assessment module determines the performance qualification of variable frequency air conditioners based on the collaborative analysis of energy efficiency performance indicators, stability performance indicators, and frequency conversion response performance indicators.

[0015] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention provides a variety of temperature and humidity combination working conditions for the variable frequency air conditioner under test through an environmental test simulation chamber with programmable temperature and humidity adjustment, effectively solving the problem that the prior art cannot systematically cover multiple working condition test scenarios, and effectively improving the representativeness and comprehensiveness of the test.

[0016] (2) This invention uses the air enthalpy difference method to analyze the output energy of air conditioners by fusing the air enthalpy difference related parameters under different environmental conditions, and evaluates the energy efficiency performance index by combining the average instantaneous energy efficiency ratio and the instantaneous energy efficiency ratio compliance rate. This enables multi-dimensional quantitative analysis of energy efficiency under different environmental conditions, accurately reflects the energy-saving performance of air conditioners under dynamic load, and provides a scientific basis for energy efficiency level determination.

[0017] (3) The present invention constructs an output energy dynamic curve based on the dynamic sequence of air conditioner output energy during continuous operation under different environmental conditions, evaluates the stability performance index by the deviation of the output energy from the reference energy dynamic curve, and objectively reflects the output stability of variable frequency air conditioner under different environmental conditions by analyzing the energy fluctuations during continuous operation, thereby improving the operational reliability of variable frequency air conditioner.

[0018] (4) Based on the output energy dynamic curves corresponding to different environmental conditions, this invention extracts the response delay time, start-up speed and transition state energy efficiency ratio during the period of cross-environmental condition change, evaluates the frequency response performance index in combination with preset standard values, conducts special evaluation on the core adjustment characteristics of frequency inverter air conditioners, effectively measures the adaptability of frequency inverter air conditioners under dynamic load changes, thereby promoting the technical optimization of frequency inverter air conditioners in terms of frequency rapid response.

[0019] (5) This invention determines the performance qualification of variable frequency air conditioners based on the synergistic analysis of energy efficiency performance indicators, stability performance indicators and frequency response performance indicators. Through the comprehensive judgment of multi-dimensional indicators, a comprehensive evaluation of the overall performance of variable frequency air conditioners is achieved, ensuring the consistency between test results and actual user experience, and improving the rigor and accuracy of air conditioner quality control. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the system module connections of the present invention.

[0022] Figure 2 This is a schematic diagram of the performance index evaluation module in this invention.

[0023] Figure 3 This is a schematic diagram of the steps for determining whether the energy efficiency performance indicators are qualified in this invention.

[0024] Figure 4 This is a schematic diagram of the steps for judging whether the stability performance index is qualified in this invention. Detailed Implementation

[0025] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. Furthermore, it should be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale.

[0026] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

[0027] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0028] Please see Figure 1 As shown, the present invention provides a dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method, including an environmental condition simulation module, an operating parameter acquisition module, a performance index evaluation module, and a performance qualification judgment module.

[0029] The connections between the modules are as follows: the environmental condition simulation module is connected to the operating parameter acquisition module; the operating parameter acquisition module is connected to the performance index evaluation module; and the performance qualification judgment module is connected to the performance index evaluation module.

[0030] The environmental condition simulation module sets up an environmental test simulation chamber with programmable temperature and humidity to provide different temperature and humidity combinations for the variable frequency air conditioner under test.

[0031] It should be noted that the environmental condition simulation module includes an environmental test simulation chamber, a temperature regulation component, and a humidity regulation component. The environmental test simulation chamber is used to place the variable frequency air conditioner under test, the temperature regulation component is used to regulate the temperature inside the environmental test simulation chamber, and the humidity regulation component is used to regulate the humidity inside the environmental test simulation chamber to simulate different temperature and humidity environmental conditions.

[0032] For example, both the temperature and humidity control components are equipped with a programmable control system, which can automatically adjust different temperature and humidity ranges through preset programs, and support automatic switching of temperature and humidity combinations at set time intervals to meet the operating condition simulation needs of variable frequency air conditioners in different seasons and regional environments.

[0033] This invention provides a variety of temperature and humidity combinations for the variable frequency air conditioner under test through a programmable temperature and humidity environment test simulation chamber, effectively solving the problem that existing technologies cannot systematically cover multiple test scenarios, and effectively improving the representativeness and comprehensiveness of the test.

[0034] The operating parameter acquisition module collects real-time air enthalpy difference related parameters of the variable frequency air conditioner under different environmental conditions. These air enthalpy difference related parameters include, but are not limited to: dry-bulb temperature, wet-bulb temperature, air pressure, air volumetric flow rate, and input power.

[0035] It should be noted that the specific contents of the operating parameter acquisition module are as follows: Parameter detection sensors are arranged on the air inlet and air outlet sides of the variable frequency air conditioner under test to collect the first dry bulb temperature, first wet bulb temperature and first air pressure of the air inlet under different environmental conditions, as well as the second dry bulb temperature, second wet bulb temperature and second air pressure of the air outlet, and to collect the real-time air volume flow rate and instantaneous input power of the variable frequency air conditioner under test during operation.

[0036] The parameter monitoring sensors include, but are not limited to: temperature and humidity sensors, air pressure sensors, flow sensors, and power sensors. The first temperature and humidity sensor and the first air pressure sensor, which are arranged on the air inlet side, are used to collect the first dry bulb temperature, first wet bulb temperature, and first air pressure of the incoming air of the variable frequency air conditioner under different environmental conditions.

[0037] The second temperature and humidity sensor and the second air pressure sensor are arranged on the air outlet side to collect the second dry bulb temperature, the second wet bulb temperature and the second air pressure of the air outlet, wherein the second temperature and humidity sensor group is located at the position after the air outlet airflow is fully mixed.

[0038] Flow sensors are used to collect the volumetric flow rate of air flowing through the evaporator or condenser of a variable frequency air conditioner, while power sensors are used to collect the input power of the variable frequency air conditioner during operation.

[0039] like Figure 2 As shown, the performance evaluation module includes an energy efficiency performance evaluation unit, a stability performance evaluation unit, and a frequency conversion response performance evaluation unit.

[0040] The energy efficiency performance evaluation unit integrates and analyzes the air conditioner's output energy based on the correlation parameters of air enthalpy difference under different environmental conditions, and evaluates the energy efficiency performance indicators based on the air conditioner's output energy.

[0041] like Figure 3 As shown, the energy efficiency performance evaluation unit includes: calculating the specific enthalpy of the inlet air and the specific enthalpy of the outlet air based on the first dry-bulb temperature, first wet-bulb temperature, and first atmospheric pressure of the inlet air and the second dry-bulb temperature, second wet-bulb temperature, and second atmospheric pressure of the outlet air under different environmental conditions using the air enthalpy difference method. The air enthalpy difference method is existing technology and will not be described in detail in this invention.

[0042] The enthalpy difference is obtained by comparing the specific enthalpy of the intake air and the specific enthalpy of the exhaust air, and then combined with the real-time air volume flow rate to calculate the air conditioner output energy.

[0043] The instantaneous energy efficiency ratio is calculated as the ratio of the air conditioner's output energy to the instantaneous input power collected by the power sensor.

[0044] The average instantaneous energy efficiency ratio and the instantaneous energy efficiency ratio compliance rate during continuous operation under different environmental conditions are statistically analyzed and compared with the target energy efficiency requirements of the corresponding environmental conditions to evaluate whether the energy efficiency performance indicators are qualified.

[0045] In one specific embodiment, when the environmental condition is a cooling test condition, the air conditioner outputs cooling energy, and its enthalpy difference is the specific enthalpy of the intake air minus the specific enthalpy of the exhaust air; when the environmental condition is a heating test condition, the air conditioner outputs heating energy, and its enthalpy difference is the specific enthalpy of the exhaust air minus the specific enthalpy of the intake air.

[0046] The analysis method for the output energy of the air conditioner is the product of the enthalpy difference and the dry air mass flow rate, where the dry air mass flow rate refers to the product of the real-time air volume flow rate and the mass of dry air in a unit volume of humid air.

[0047] The mass of dry air per unit volume of moist air depends on the dry-bulb temperature, wet-bulb temperature, and atmospheric pressure at the measurement point. The density of moist air is obtained based on the standard formula of the ideal gas law, where the density of moist air is the mass of dry air per unit volume of moist air.

[0048] When calculating the instantaneous energy efficiency ratio compliance rate, the energy efficiency performance evaluation unit determines whether each instantaneous energy efficiency ratio sample is greater than or equal to the minimum allowable energy efficiency ratio threshold corresponding to the operating condition, counts the number of samples that are greater than or equal to the minimum allowable energy efficiency ratio threshold corresponding to the operating condition, and uses the ratio of the number of such samples to the total number of samples as the instantaneous energy efficiency ratio compliance rate.

[0049] It should be noted that the evaluation process for whether the energy efficiency performance indicators are qualified is as follows: if the average value of all instantaneous energy efficiency ratios during continuous operation under a certain environmental condition is greater than the minimum allowable energy efficiency ratio threshold for the corresponding environmental condition, and the compliance rate of instantaneous energy efficiency ratios during continuous operation under that environmental condition is greater than the set compliance rate threshold, then the energy efficiency performance indicators of that environmental condition are qualified; otherwise, the energy efficiency performance indicators of that environmental condition are unqualified.

[0050] The threshold for the compliance rate is determined based on the product standard of the inverter air conditioner under test. For household inverter air conditioners, the threshold for the compliance rate can be set to 90%.

[0051] This invention uses the air enthalpy difference method to analyze the output energy of air conditioners by fusing the correlation parameters of air enthalpy difference under different environmental conditions. It combines the average instantaneous energy efficiency ratio and the instantaneous energy efficiency ratio compliance rate to evaluate energy efficiency performance indicators, thereby realizing multi-dimensional quantitative analysis of energy efficiency under different environmental conditions. This accurately reflects the energy-saving performance of air conditioners under dynamic loads and provides a scientific basis for energy efficiency rating determination.

[0052] The stability performance evaluation unit constructs an output energy dynamic curve based on the dynamic sequence of air conditioner output energy during continuous operation under different environmental conditions, and evaluates the stability performance index by the deviation of the curve from the reference energy dynamic curve.

[0053] It should be noted that the stability performance evaluation unit includes: generating a dynamic sequence of air conditioner output energy by sorting the air conditioner output energy at all time points during continuous operation under different environmental conditions according to time.

[0054] A planar coordinate system is constructed with time points as the horizontal axis and air conditioner output energy as the vertical axis. Points are plotted in the constructed planar coordinate system according to the dynamic sequence of air conditioner output energy, and the points are connected to form a dynamic curve of output energy.

[0055] Different environmental conditions are clustered into multiple categories, and the output energy dynamic curves corresponding to all environmental conditions in the multiple categories are overlapped and fitted to generate a reference energy dynamic curve.

[0056] The deviation of the output energy dynamic curves under different environmental conditions and their corresponding reference energy dynamic curves is analyzed to obtain the degree of curve deviation. The stability performance index is then evaluated based on the degree of curve deviation.

[0057] In one specific embodiment, the method for clustering different environmental conditions into multiple categories is as follows: Temperature and humidity under different environmental conditions are Z-score standardized, and K centroids are randomly initialized for the standardized temperature and humidity. The value of K is determined using the elbow method. By calculating the sum of squared clustering errors corresponding to different K values, a curve of the sum of squared clustering errors versus K values ​​is plotted. The K value corresponding to the abrupt change in the rate of decline of the curve is selected as the optimal number of clusters, ensuring that the clustering results avoid overfitting while maintaining class discriminability.

[0058] Calculate the Euclidean distance between temperature and humidity and K centroids under different environmental conditions, and assign the temperature and humidity under different environmental conditions to the clusters containing the nearest centroids to form K temporary clusters.

[0059] The mean values ​​of temperature and humidity under all environmental conditions in each temporary cluster are recalculated and used as the centroid of each temporary cluster.

[0060] Repeat the above steps until the centroid position stabilizes, ultimately forming K stable clusters, which represent multiple categories. This invention uses K-means clustering to classify environmental conditions, achieving reasonable grouping of conditions through Euclidean distance and centroid iteration, avoiding the subjectivity of manual classification and providing an objective basis for the generation of reference curves.

[0061] It should be noted that the reference energy dynamic curve is generated as follows: taking the timestamp of the environmental condition switching command as zero point, the output energy dynamic curves corresponding to all environmental conditions in multiple categories are aligned on the time axis, and the standard deviation, mean, and median of the output energy at each time point in multiple categories are calculated.

[0062] When the standard deviation of the output energy at a certain time point is greater than the set standard deviation threshold for output energy, the median output energy at that time point is used as the reference output energy; otherwise, the mean output energy at that time point is used as the reference output energy. The set standard deviation threshold for output energy is determined based on the mean standard deviation of output energy from historical test data of similar air conditioners under standard operating conditions.

[0063] The reference output energies at each time point in multiple categories are smoothly connected in chronological order to form dynamic curves of reference energies corresponding to multiple categories.

[0064] This invention combines the standard deviation of output energy to determine the reference value. When the data is discrete, the median is selected, and when the data is concentrated, the mean is selected as the reference value. This takes into account the influence of outliers and makes the reference curve more representative of the typical dynamic characteristics of similar working conditions.

[0065] like Figure 4 As shown, in one specific embodiment, the evaluation method for whether the stability performance index is qualified is as follows: the output energy dynamic curve corresponding to different environmental conditions is compared with the reference energy dynamic curve in the corresponding environmental condition category, and the non-overlapping line segments corresponding to the output energy dynamic curve and the reference energy dynamic curve are selected.

[0066] The variation functions of the non-coincident line segments in the output energy dynamic curve and its reference energy dynamic curve are fitted, and the degree of curve deviation is obtained by difference integral operation. The difference integral operation takes the entire cycle of continuous operation under environmental conditions as the integration interval, and integrates the absolute value of the difference between the output energy dynamic curve and the reference curve over time. The integration result is the degree of curve deviation, reflecting the cumulative deviation over the entire cycle.

[0067] If the deviation of the curve under a certain environmental condition is less than or equal to the set curve deviation threshold, then the stability performance index of that environmental condition is qualified; otherwise, the stability performance index of that environmental condition is unqualified.

[0068] This invention constructs an output energy dynamic curve based on the dynamic sequence of air conditioner output energy during continuous operation under different environmental conditions, and evaluates the stability performance index by the deviation of the output energy from the reference energy dynamic curve. By analyzing the energy fluctuations during continuous operation, it can objectively reflect the output stability of the inverter air conditioner under different environmental conditions and improve the operational reliability of the inverter air conditioner.

[0069] The frequency converter response performance evaluation unit extracts the response delay time, start-up speed and transient energy efficiency ratio during the period of cross-environmental operating condition change based on the output energy dynamic curves corresponding to different environmental operating conditions, and evaluates the frequency converter response performance indicators in combination with preset standard values.

[0070] The preset standard values ​​include the allowable response delay time, the minimum allowable start-up speed threshold, and the minimum allowable energy efficiency ratio threshold for the corresponding environmental conditions of the variable frequency air conditioner. The preset standard values ​​are determined according to the design specifications of the variable frequency air conditioner under test.

[0071] It should be noted that the method for obtaining the response delay time, startup speed and transition state energy efficiency ratio during the cross-environmental operating condition change period is as follows: sort the output energy dynamic curves corresponding to different environmental operating conditions according to the timestamp, record the time when the output energy changes after each cross-environmental operating condition change, and take the difference between the output energy and the corresponding cross-environmental operating condition change time as the response delay time.

[0072] Record the time when the output energy reaches a stable value based on the dynamic curve of the output energy after each cross-environmental operating condition change. Take the time when the energy reaches a stable value and the time when the output energy changes as the change period. Determine the start-up speed based on the slope of the change period on the dynamic curve of the output energy.

[0073] Collect the total input power and output energy during each period of cross-environmental operating condition changes, and use the ratio of output energy to total input power as the transient energy efficiency ratio.

[0074] The evaluation method for the variable frequency response performance index is as follows: the response delay time, start-up speed, and transitional energy efficiency ratio of each cross-environmental operating condition change period are compared with the preset allowable response delay time, allowable minimum start-up speed threshold, and minimum allowable energy efficiency ratio threshold of the corresponding environmental operating condition. If the response delay time of each cross-environmental operating condition change period is less than the allowable response delay time of the variable frequency air conditioner, the start-up speed is higher than the allowable minimum start-up speed threshold, and the transitional energy efficiency ratio is greater than the minimum allowable energy efficiency ratio threshold of the corresponding environmental operating condition, then the variable frequency response performance index of the variable frequency air conditioner is qualified; otherwise, the variable frequency response performance index of the variable frequency air conditioner is unqualified.

[0075] This invention extracts the response delay time, start-up speed, and transitional energy efficiency ratio during periods of change in environmental conditions based on the dynamic curves of output energy corresponding to different environmental conditions. It evaluates the frequency response performance indicators in combination with preset standard values, conducts a special evaluation on the core regulation characteristics of frequency inverter air conditioners, effectively measures the adaptability of frequency inverter air conditioners under dynamic load changes, and thus promotes the technical optimization of frequency inverter air conditioners in terms of frequency rapid response.

[0076] The performance qualification assessment module determines the performance qualification of variable frequency air conditioners based on the collaborative analysis of energy efficiency performance indicators, stability performance indicators, and frequency conversion response performance indicators.

[0077] It should be noted that the performance qualification criteria for the inverter air conditioner are as follows: if the energy efficiency performance index, stability performance index, and inverter response performance index of the inverter air conditioner are all qualified, then the performance qualification of the inverter air conditioner is determined to meet the standard; otherwise, the performance qualification of the inverter air conditioner is determined to not meet the standard.

[0078] This invention determines the performance qualification of variable frequency air conditioners based on the synergistic analysis of energy efficiency performance indicators, stability performance indicators, and frequency response performance indicators. Through the comprehensive judgment of multi-dimensional indicators, it achieves a comprehensive evaluation of the overall performance of variable frequency air conditioners, ensuring the consistency between test results and actual user experience, and improving the rigor and accuracy of air conditioner quality control.

[0079] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0080] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0081] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0082] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0083] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0084] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dynamic performance testing system for variable frequency air conditioners based on the air enthalpy difference method, characterized in that, include: The environmental condition simulation module sets up an environmental test simulation chamber with programmable temperature and humidity adjustment to provide different temperature and humidity combinations for the variable frequency air conditioner under test. The operation parameter acquisition module collects real-time air enthalpy difference related parameters of the variable frequency air conditioner under different environmental conditions; The performance evaluation module includes an energy efficiency performance evaluation unit, a stability performance evaluation unit, and a frequency conversion response performance evaluation unit. The energy efficiency performance evaluation unit integrates and analyzes the air conditioner output energy based on the air enthalpy difference correlation parameters under different environmental conditions, and evaluates the energy efficiency performance indicators based on the air conditioner output energy. The stability performance evaluation unit constructs an output energy dynamic curve based on the dynamic sequence of air conditioner output energy during continuous operation under different environmental conditions, and evaluates the stability performance index by the deviation of the curve from the reference energy dynamic curve. The frequency converter response performance evaluation unit extracts the response delay time, start-up speed and transient energy efficiency ratio during the period of cross-environmental operating condition change based on the output energy dynamic curves corresponding to different environmental operating conditions, and evaluates the frequency converter response performance indicators in combination with preset standard values. The response delay time, startup speed, and transition state energy efficiency ratio are obtained by sorting the output energy dynamic curves corresponding to different environmental conditions according to timestamps, recording the time when the output energy changes after each cross-environmental condition change, and using the difference between the output energy and the corresponding cross-environmental condition change time as the response delay time. Record the time when the output energy reaches a stable value based on the dynamic curve of the output energy after each cross-environmental operating condition change. Take the time when the energy reaches a stable value and the time when the output energy changes as the change period. Determine the start-up speed based on the slope of the change period on the dynamic curve of the output energy. Collect the total input power and output energy during each period of cross-environmental operating condition changes, and use the ratio of output energy to total input power as the transient energy efficiency ratio; The performance qualification assessment module determines the performance qualification of variable frequency air conditioners based on the collaborative analysis of energy efficiency performance indicators, stability performance indicators, and frequency conversion response performance indicators.

2. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 1, characterized in that: The specific contents of the operating parameter acquisition module are as follows: Parameter detection sensors are placed on the air inlet and air outlet sides of the variable frequency air conditioner under test to collect the first dry bulb temperature, first wet bulb temperature and first air pressure of the air inlet under different environmental conditions, as well as the second dry bulb temperature, second wet bulb temperature and second air pressure of the air outlet. The real-time air volume flow rate and instantaneous input power of the variable frequency air conditioner under test are also collected during operation.

3. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 2, characterized in that: The energy efficiency performance evaluation unit includes: Based on the first dry-bulb temperature, first wet-bulb temperature and first atmospheric pressure of the intake air and the second dry-bulb temperature, second wet-bulb temperature and second atmospheric pressure of the exhaust air under different environmental conditions, the specific enthalpy of the intake air and the specific enthalpy of the exhaust air are calculated by the air enthalpy difference method. The enthalpy difference is obtained by comparing the specific enthalpy of the intake air and the specific enthalpy of the exhaust air, and then combined with the real-time air volume flow rate to calculate the air conditioner output energy. The instantaneous energy efficiency ratio is calculated as the ratio of the air conditioner's output energy to the instantaneous input power collected by the power sensor. The average instantaneous energy efficiency ratio and the instantaneous energy efficiency ratio compliance rate during continuous operation under different environmental conditions are statistically analyzed and compared with the target energy efficiency requirements of the corresponding environmental conditions to evaluate whether the energy efficiency performance indicators are qualified.

4. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 3, characterized in that: The evaluation process for whether the energy efficiency performance indicators are qualified is as follows: If the average value of all instantaneous energy efficiency ratios during continuous operation under a certain environmental condition is greater than the minimum allowable energy efficiency ratio threshold for the corresponding environmental condition, and the compliance rate of instantaneous energy efficiency ratios during continuous operation under that environmental condition is greater than the set compliance rate threshold, then the energy efficiency performance index of that environmental condition is qualified; otherwise, the energy efficiency performance index of that environmental condition is unqualified.

5. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 1, characterized in that: The stability performance evaluation unit includes the following: The air conditioning output energy at all time points during continuous operation under different environmental conditions is sorted by time to generate a dynamic sequence of air conditioning output energy. A planar coordinate system is constructed with time points as the horizontal axis and air conditioner output energy as the vertical axis. Points are plotted in the constructed planar coordinate system according to the dynamic sequence of air conditioner output energy, and the points are connected to form a dynamic curve of output energy. Different environmental conditions are clustered into multiple categories, and the output energy dynamic curves corresponding to all environmental conditions in the multiple categories are overlapped and fitted to generate a reference energy dynamic curve. The deviation of the output energy dynamic curves under different environmental conditions and their corresponding reference energy dynamic curves is analyzed to obtain the degree of curve deviation. The stability performance index is then evaluated based on the degree of curve deviation.

6. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 5, characterized in that: The reference energy dynamic curve is generated as follows: Using the timestamp of the environmental condition switching command as zero point, the output energy dynamic curves corresponding to all environmental conditions in multiple categories are aligned on the time axis, and the standard deviation, mean, and median of the output energy at each time point in multiple categories are statistically analyzed. When the standard deviation of the output energy at a certain time point is greater than the set standard deviation threshold of the output energy, the median of the output energy at that time point is used as the reference output energy; otherwise, the mean of the output energy at that time point is used as the reference output energy. The reference output energies at each time point in multiple categories are smoothly connected in chronological order to form dynamic curves of reference energies corresponding to multiple categories.

7. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 5, characterized in that: The evaluation method for whether the stability performance index is qualified is as follows: The output energy dynamic curves corresponding to different environmental conditions are compared with the reference energy dynamic curves in the corresponding environmental condition category, and the non-overlapping line segments of the output energy dynamic curves and their reference energy dynamic curves are filtered out. The variation function of the non-coincident line segment in the output energy dynamic curve and its reference energy dynamic curve is fitted, and the degree of curve deviation is obtained by difference integral operation. If the deviation of the curve under a certain environmental condition is less than or equal to the set curve deviation threshold, then the stability performance index of that environmental condition is qualified; otherwise, the stability performance index of that environmental condition is unqualified.

8. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 1, characterized in that: The evaluation method for the frequency conversion response performance index is as follows: The response delay time, start-up speed, and transitional energy efficiency ratio of each cross-environmental operating condition change period are compared with the preset allowable response delay time, allowable minimum start-up speed threshold, and minimum allowable energy efficiency ratio threshold for the corresponding environmental operating condition. If the response delay time of each cross-environmental operating condition change period is less than the allowable response delay time of the inverter air conditioner, the start-up speed is higher than the allowable minimum start-up speed threshold, and the transitional energy efficiency ratio is greater than the minimum allowable energy efficiency ratio threshold for the corresponding environmental operating condition, then the inverter air conditioner's inverter response performance indicators are qualified; otherwise, the inverter air conditioner's inverter response performance indicators are unqualified.

9. The variable frequency air conditioner performance dynamic testing system based on the air enthalpy difference method according to claim 1, characterized in that: The performance qualification criteria for the inverter air conditioner are as follows: if the energy efficiency performance index, stability performance index, and inverter response performance index of the inverter air conditioner are all qualified, then the performance qualification of the inverter air conditioner is determined to meet the standard; otherwise, the performance qualification of the inverter air conditioner is determined to not meet the standard.

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