A method and system for testing heat exchange performance of an electric compressor based on multi-parameter acquisition

Abstract

This invention relates to the field of testing and control technology for thermal management systems of new energy vehicles, and provides a method and system for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition. The method includes: before the start of the heat exchange performance test, acquiring the current opening control parameters of the electronic expansion valve in the jet branch, and adjusting them to the target opening range if they are not within it before performing the heat exchange performance test, thereby reducing fluctuations in the refrigerant mass flow rate in the main circuit. Compared to existing technologies that only handle fluctuations through filtering or compensation after the test, this invention moves fluctuation control forward to before the test, reducing the fluctuations in the refrigerant mass flow rate in the main circuit from the source, reducing the compensation amplitude and the errors introduced during subsequent data processing, thereby improving the accuracy and stability of the heat exchange performance test results.

Description

Technical Field

[0001] This invention belongs to the field of testing and control technology for thermal management systems of new energy vehicles, and particularly relates to a method and system for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition. Background Technology

[0002] With the development of new energy vehicles, the role of thermal management systems in vehicle energy efficiency and range performance is becoming increasingly prominent. Electric compressors, as key components of thermal management systems, are widely used in air conditioning refrigeration and heat pump heating processes. Among them, jet-induced enthalpy-enhanced electric compressors are widely used due to their superior heating capacity in low-temperature environments. In practical applications, these electric compressors typically require heat exchange performance tests under various coupled operating conditions to evaluate their performance under different ambient temperatures, compressor operating parameters, and thermal loads. This is especially true under low-temperature heating conditions, such as simultaneously meeting the heating load of the passenger compartment and the battery thermal management load, which places higher demands on their performance testing.

[0003] In existing technologies, the heat exchange performance testing of electric compressors is typically performed on a test bench. During the test, equipment such as mass flow meters, temperature sensors, and pressure sensors are used to collect data on the mass flow rate, temperature, and pressure of the refrigerant in the main circuit, and performance indicators such as heat exchange are calculated based on the collected data. However, under low-temperature heating conditions, the refrigerant flow state in the main circuit is prone to instability due to the combined effects of compressor suction pulsation, jet branch coupling, and refrigerant flashing effects, resulting in fluctuations in the mass flow measurement results over a certain period of time. For such fluctuations, when they are within a reasonable range, existing technologies usually treat them as random disturbances during the testing process and correct them using filtering algorithms or compensation methods in subsequent data processing.

[0004] However, those skilled in the art have discovered through long-term testing practice that the aforementioned mass flow rate fluctuations are not entirely random. The degree of fluctuation directly impacts the compensation range and errors in subsequent data processing. When the fluctuation range is large, the required compensation increases, and the compensation error also increases, thus affecting the accuracy of the heat exchange performance test results. Furthermore, existing technologies primarily rely on post-test compensation methods, lacking the technical means to optimize and adjust key control parameters affecting fluctuations before testing, making it difficult to reduce fluctuations at the source. Therefore, how to reasonably adjust relevant control parameters before testing to reduce refrigerant mass flow rate fluctuations in the main loop and improve test accuracy has become a pressing technical problem to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition, in order to solve the problems mentioned in the background art.

[0006] This invention is implemented as follows: a method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition, the method comprising:

[0007] S1. When the target electric compressor is under a preset coupling condition for heat exchange performance testing, retrieve the preset historical test database and select a number of historical test samples that correspond to the current test condition.

[0008] S2. Extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample.

[0009] S3. Based on the refrigerant mass flow rate data of the main circuit, calculate the main circuit mass flow rate fluctuation coefficient of each historical test sample, and establish the correspondence between the opening control parameter of the electronic expansion valve of the jet branch and the main circuit mass flow rate fluctuation coefficient. Based on the correspondence, determine the target opening range that reduces the main circuit mass flow rate fluctuation coefficient.

[0010] S4. Before the current heat exchange performance test begins, obtain the current opening control parameters of the electronic expansion valve in the jet branch, and if they are not within the target opening range, adjust them to the target opening range before performing the heat exchange performance test to reduce the fluctuation of refrigerant mass flow in the main circuit.

[0011] As a further limitation of the technical solution of the present invention, the target electric compressor is a jet enthalpy-increasing electric compressor.

[0012] As a further limitation of the technical solution of the embodiment of the present invention, the preset coupling condition is a low temperature heating condition, and under the condition, the electric compressor is in the state of opening the jet branch.

[0013] As a further limitation of the technical solution of the present invention, the "correspondence with the current test conditions" means that the historical test samples and the current heat exchange performance test are the same as or within a preset error range in at least one or more of the following: ambient temperature, compressor operating parameters and heat load conditions.

[0014] As a further limitation of the technical solution of this embodiment of the invention, step S3 specifically includes:

[0015] Time series analysis is performed on the refrigerant mass flow data of the main circuit within a preset time period in each historical test sample, and the fluctuation amplitude and dispersion of the mass flow data within the preset time period are calculated based on the mass flow data. The corresponding main circuit mass flow fluctuation coefficient is obtained by combining the fluctuation amplitude and dispersion.

[0016] Several historical test samples were sorted from small to large according to the opening control parameter of the electronic expansion valve of the jet branch, and a sample sequence was constructed. The main loop mass flow fluctuation coefficient corresponding to each historical test sample in the sample sequence was extracted to establish the correspondence between the opening control parameter of the electronic expansion valve of the jet branch and the main loop mass flow fluctuation coefficient.

[0017] Based on the correspondence, trend analysis is performed to identify the range characteristics of the main circuit mass flow fluctuation coefficient as a function of the jet branch electronic expansion valve opening control parameter. When there is a trend of the main circuit mass flow fluctuation coefficient first decreasing and then increasing, the range of jet branch electronic expansion valve opening control parameters corresponding to the opening range with relatively low main circuit mass flow fluctuation coefficient is determined as the target opening range.

[0018] As a further limitation of the technical solution of the present invention, the specific calculation method of the main circuit mass flow rate fluctuation coefficient includes: weighting the fluctuation amplitude and the dispersion according to a preset weighting coefficient to obtain the main circuit mass flow rate fluctuation coefficient; wherein, the fluctuation amplitude is used to characterize the range of change of the main circuit refrigerant mass flow rate data within a preset time period, and the dispersion is used to characterize the dispersion level of the main circuit refrigerant mass flow rate data within the preset time period.

[0019] As a further limitation of the technical solution of this embodiment of the invention, step S4 includes:

[0020] Before conducting the current heat exchange performance test on the target electric compressor, obtain the current jet branch electronic expansion valve opening control parameters;

[0021] Determine whether the current opening control parameter of the electronic expansion valve in the jet branch is within the target opening range. If so, perform a heat exchange performance test.

[0022] If not, the opening control parameters of the current jet branch electronic expansion valve are adjusted to bring it into the target opening range before performing the heat exchange performance test, so as to reduce the fluctuation of the refrigerant mass flow rate in the main circuit and improve the accuracy of the heat exchange performance test.

[0023] A test system for the heat exchange performance of an electric compressor based on multi-parameter acquisition, the system comprising:

[0024] The sample screening module is used to retrieve a preset historical test database and screen a number of historical test samples corresponding to the current test conditions when the target electric compressor is under preset coupling conditions for heat exchange performance testing.

[0025] The data extraction module is used to extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample.

[0026] The relationship building module is used to calculate the main circuit mass flow fluctuation coefficient of each historical test sample based on the main circuit refrigerant mass flow data, and to establish the correspondence between the opening control parameters of the electronic expansion valve of the jet branch and the main circuit mass flow fluctuation coefficient. Based on the correspondence, the target opening range that reduces the main circuit mass flow fluctuation coefficient is determined.

[0027] The control and adjustment module is used to obtain the current opening control parameters of the electronic expansion valve of the jet branch before the start of the current heat exchange performance test, and adjust them to the target opening range before performing the heat exchange performance test if they are not within the target opening range, so as to reduce the fluctuation of refrigerant mass flow in the main circuit.

[0028] As a further limitation of the technical solution of the present invention, the target electric compressor is a jet enthalpy-increasing electric compressor.

[0029] As a further limitation of the technical solution of the embodiment of the present invention, the preset coupling condition is a low temperature heating condition, and under the condition, the electric compressor is in the state of opening the jet branch.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This invention establishes a correspondence between the opening control parameters of the electronic expansion valve in the jet branch and the mass flow rate fluctuation coefficient of the main loop based on historical test sample data. It also identifies the target opening range that minimizes the mass flow rate fluctuation coefficient and actively adjusts the opening control parameters before the start of the current heat exchange performance test. Compared to existing technologies that only address fluctuations after testing through filtering or compensation, this invention moves fluctuation control forward to before testing, reducing the main loop refrigerant mass flow rate fluctuation at its source. This reduces the compensation amplitude and the resulting errors during subsequent data processing, thereby improving the accuracy and stability of the heat exchange performance test results. Furthermore, this invention achieves correlation modeling between control parameters and fluctuation characteristics through multi-parameter data analysis, enhancing the controllability and repeatability of the testing process and demonstrating significant engineering application value. Attached Figure Description

[0032] Figure 1 A flowchart of the method provided in the embodiments of the present invention;

[0033] Figure 2 This is a flowchart illustrating the method for determining the target opening interval provided in the embodiments of the present invention;

[0034] Figure 3 This is a flowchart illustrating the active adjustment of the opening control parameters in the method provided by the embodiments of the present invention;

[0035] Figure 4 The application architecture diagram of the system provided in the embodiments of the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0037] Figure 1 A flowchart of the method provided by an embodiment of the present invention is shown.

[0038] Specifically, a method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition includes the following steps:

[0039] Step S1: When the target electric compressor is under a preset coupling condition for heat exchange performance testing, a preset historical test database is retrieved, and several historical test samples corresponding to the current test condition are selected. The target electric compressor is a vapor injection enthalpy-increasing electric compressor. The vapor injection enthalpy-increasing electric compressor includes a main refrigerant circuit and a vapor injection branch. An electronic expansion valve is installed on the vapor injection branch to regulate the vapor injection flow rate.

[0040] The preset coupling condition is a low-temperature heating condition, and under this condition, the electric compressor is in the jet branch open state to simultaneously meet the coupled operation conditions of the crew cabin heating load and the battery thermal management load.

[0041] The phrase "corresponding to the current test conditions" means that the historical test samples and the current heat exchange performance test are the same as or within a preset error range in at least one or more of the following: ambient temperature, compressor operating parameters, and heat load conditions.

[0042] In this embodiment of the invention, the invention is an improved application based on the existing electric compressor heat exchange performance testing system, and is mainly applied to the testing scenario of vapor injection enthalpy-increasing electric compressors. The vapor injection enthalpy-increasing electric compressor includes a main refrigerant circuit and a vapor injection branch. An electronic expansion valve is installed on the vapor injection branch to regulate the flow rate of refrigerant injected into the intermediate cavity of the compressor, thereby affecting the intermediate pressure state and suction state of the compressor.

[0043] In the thermal management system of new energy vehicles, the heat exchange performance of this type of electric compressor typically needs to be tested under various coupled operating conditions, among which the low-temperature heating condition is one of the important test scenarios. Under this condition, the electric compressor is in the jet branch open state, and jet injection is used to simultaneously meet the coupled operation requirements of the passenger compartment heating load and the battery thermal management load.

[0044] During actual testing, those skilled in the art will recognize that under the aforementioned low-temperature heating conditions, due to the combined effects of compressor suction pulsation, jet branch coupling, and refrigerant flashing, the refrigerant flow state in the main loop exhibits unstable characteristics. This results in fluctuations in the main loop refrigerant mass flow rate data within a preset time period. The preset time period can be a continuous interval during the heat transfer performance test, such as the initial stage when the system is not yet fully stable, or the sampling period after the system has entered stable operation, as long as it reflects the fluctuation characteristics of the main loop refrigerant mass flow rate. Such fluctuations are generally considered normal within a preset range. Existing technologies typically treat them as random disturbances during the test process and correct them through filtering or compensation methods in subsequent data processing. For example, smoothing can be performed based on a moving average algorithm, or the mass flow rate data can be compensated using an empirical model to improve the stability of the heat transfer performance calculation results.

[0045] However, those skilled in the art, through analysis of a large number of historical test samples, have discovered that the fluctuations in the refrigerant mass flow rate in the main circuit are not entirely random, but rather correlated with the opening control parameters of the electronic expansion valve in the jet branch. These opening control parameters are typically adjusted by the control system based on the operating status, or set by personnel during testing. They are used to control the jet flow rate, thereby affecting the intermediate pressure distribution of the compressor and the refrigerant flow state in the main circuit.

[0046] Furthermore, those skilled in the art have discovered that, under the same or similar test conditions, the opening control parameter of the electronic expansion valve in the jet branch varies within a certain range during different test processes. This variation stems from factors such as differences in control strategies, system response characteristics, and manual adjustments. Although the variation in this opening control parameter is small, it has a direct impact on the stability of refrigerant flow in the main circuit, thereby causing changes in the degree of fluctuation in the refrigerant mass flow rate in the main circuit.

[0047] Comparative analysis of historical test samples under the same operating conditions revealed a nonlinear relationship between the opening control parameter of the electronic expansion valve in the jet branch and the mass flow fluctuation coefficient of the main circuit. When the opening was small, insufficient jet volume led to unstable intermediate pressure and large fluctuations in the compressor's suction state, resulting in large fluctuations in mass flow. When the opening was moderate, reasonable jet compensation stabilized the intermediate pressure, and the refrigerant flow in the main circuit was most stable, with relatively small fluctuations in mass flow. However, when the opening was large, excessive jet volume increased two-phase disturbances and aggravated suction pulsation, leading to further increases in mass flow fluctuation, thus exhibiting an overall trend of first decreasing and then increasing.

[0048] Based on the above research, the core of this invention lies in: establishing a correspondence between the opening control parameters of the electronic expansion valve in the jet branch and the main circuit mass flow rate fluctuation coefficient by utilizing historical test samples corresponding to the current test conditions in the historical test database, and identifying the opening control parameter range that makes the main circuit mass flow rate fluctuation coefficient relatively low; before the current heat exchange performance test begins, adjusting the opening control parameters of the electronic expansion valve in the jet branch to the opening control parameter range, reducing the main circuit refrigerant mass flow rate fluctuation from the source, avoiding the increase in subsequent compensation processing and error accumulation due to large fluctuation amplitude, thereby improving the accuracy and stability of the heat exchange performance test.

[0049] Based on this, step S1 first requires identifying whether the target electric compressor is under the preset coupling condition. Specifically, this can be determined by obtaining the ambient temperature of the current test system, the compressor's operating status, and the system load. When the ambient temperature is lower than the preset temperature threshold, the compressor is in heating mode and the jet branch is open, and there are both crew compartment heating loads and battery thermal management loads, it can be determined that the current condition is the low-temperature heating coupling condition.

[0050] Specifically, the preset historical test database may include the following types of underlying data: refrigerant mass flow rate data, temperature data, pressure data, and compressor operating parameter data (such as compressor speed, operating mode, etc.) collected under various test conditions. It also includes control parameters such as the opening control parameters of the electronic expansion valve in the jet branch. This data is typically acquired through mass flow meters, temperature sensors, pressure sensors, and controllers, all of which are standard measurement and acquisition methods in existing test systems. For example, refrigerant mass flow rate data is obtained through a Coriolis mass flow meter, temperature data is obtained through thermocouples or temperature sensors, and suction and discharge pressure data is obtained through pressure sensors.

[0051] In this embodiment of the invention, the identification of the preset coupling condition can be achieved by determining the operating parameters collected in real time by the current test system. Specifically, it can be based on a comprehensive judgment of conditions such as whether the ambient temperature is lower than a preset temperature threshold, whether the compressor is in heating mode, whether the jet branch is open, and whether the system simultaneously has crew cabin heating requirements and battery thermal management requirements. When the above conditions are met, it can be determined that the current operating condition is the low-temperature heating coupling condition. The above determination method can be implemented by the controller performing logical judgment on the data collected by each sensor and the operating status signals, which is a conventional control and identification method in the art.

[0052] After completing the operating condition identification, historical test samples corresponding to the current test condition are selected from a pre-set historical test database. The purpose is to obtain the true correlation between the opening control parameters of the electronic expansion valve in the jet branch and the mass flow fluctuation in the main circuit under the same or similar operating conditions, thereby providing a data foundation for establishing the correspondence between the two. This step directly echoes the aforementioned core research point, namely, to mine the influence pattern of the opening control parameters on mass flow fluctuation through historical samples.

[0053] To ensure the validity and reliability of this correspondence, this embodiment employs relatively stringent sample selection criteria. Specifically, historical test samples must be identical to or within a preset error range in at least one or more of the following conditions: ambient temperature, compressor operating parameters, and thermal load. This stringent selection is necessary because the mass flow rate fluctuation is influenced not only by the opening control parameters of the electronic expansion valve in the jet branch but also by the coupled effects of multiple factors such as ambient temperature, compressor operating status, and system load. If the selection criteria are too lenient, other interfering factors can be introduced, weakening the correlation between the opening control parameters and the fluctuation, thereby affecting the accuracy of identifying the target opening range.

[0054] Meanwhile, this embodiment does not require all parameters to be completely identical, but allows them to be within a preset error range. This is because it is difficult to achieve complete consistency of all parameters during actual testing, and deviations within an appropriate range will not change the main operating characteristics of the system. The preset error range can be set according to the measurement accuracy of the test system, the distribution of historical data, and engineering experience. For example, the ambient temperature is allowed to vary within ± a certain temperature difference range, the compressor speed is allowed to fluctuate within a certain speed deviation range, and the heat load is allowed to vary within a certain proportion range. By introducing a preset error range, the number of usable samples can be increased while ensuring sample similarity, thereby enhancing the stability and reliability of subsequent data analysis.

[0055] In addition to ambient temperature, compressor operating parameters, and thermal load conditions, other operating parameters can be introduced as screening conditions as needed, such as suction pressure, discharge pressure, superheat, or system operating mode, to further improve the accuracy of sample matching, but are not limited to the above parameters.

[0056] After screening historical test samples in the above manner, a reliable data foundation can be provided for establishing the correspondence between the opening control parameters of the jet branch electronic expansion valve and the mass flow fluctuation coefficient of the main circuit in subsequent steps, thereby achieving accurate identification of the target opening range.

[0057] Furthermore, the method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition also includes the following steps:

[0058] Step S2: Extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample.

[0059] In this embodiment of the invention, the opening control parameter of the jet branch electronic expansion valve is a control parameter predetermined before the start of the heat exchange performance test. It is used to characterize the target opening state of the jet branch electronic expansion valve and to control the jet flow rate in the jet branch. Specifically, during the test preparation phase, the test system typically pre-determines the opening control parameter of the jet branch electronic expansion valve based on a preset test plan, control strategy, or manually set results, so that the jet branch electronic expansion valve reaches the corresponding opening state before the test begins.

[0060] The opening control parameters of the jet branch electronic expansion valve can be generated by the controller according to preset control logic, or they can be input or modified by the test personnel through the test interface according to the current test requirements. For example, in some test scenarios, the opening control parameters of the jet branch electronic expansion valve can be predetermined based on the target intermediate pressure, target jet volume, or empirical calibration parameters; in other test scenarios, the test personnel can directly set the opening control parameters of the jet branch electronic expansion valve according to the current test task. Regardless of the method used, the opening control parameters of the jet branch electronic expansion valve already exist before the start of the current heat exchange performance test and can be read and recorded by the test system.

[0061] In this embodiment of the invention, if it is necessary to actively adjust the opening control parameters of the jet branch electronic expansion valve, the controller can correct the existing opening control parameters of the jet branch electronic expansion valve according to the determined target opening range before the current heat exchange performance test begins, and output corresponding control commands to the jet branch electronic expansion valve. The control commands can be expressed as opening percentage commands, stepper motor step count commands, or other control signals that can characterize the target valve opening. In this way, the pre-adjustment of the jet branch electronic expansion valve opening control parameters can be completed before the formal start of the current heat exchange performance test.

[0062] The extraction of the jet branch electronic expansion valve opening control parameters from historical test samples can be achieved by retrieving valve control commands, valve opening setting records, or corresponding feedback records recorded by the control system during historical tests. In other words, the jet branch electronic expansion valve opening control parameters in historical test samples are essentially control parameters that were predetermined before the start of each historical heat exchange performance test and executed during the test. Recording and retrieving these control parameters is a standard data storage and retrieval method in existing test systems.

[0063] The main loop refrigerant mass flow rate data is used to characterize the flow state of the refrigerant in the main refrigerant loop and is typically obtained through a mass flow rate measuring device installed in the main refrigerant loop. Specifically, a Coriolis mass flow meter can be used to directly measure the main loop refrigerant mass flow rate. This type of device can output continuous mass flow rate data, suitable for forming the subsequent required main loop refrigerant mass flow rate data sequence. In other embodiments, other flow rate measuring devices available in the art for refrigerant flow rate measurement can also be used, as long as they can obtain the main loop refrigerant mass flow rate data.

[0064] Furthermore, the method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition also includes the following steps:

[0065] Step S3: Based on the refrigerant mass flow rate data of the main circuit, calculate the main circuit mass flow rate fluctuation coefficient of each historical test sample, and establish the correspondence between the opening control parameters of the electronic expansion valve of the jet branch and the main circuit mass flow rate fluctuation coefficient. Based on the correspondence, determine the target opening range that reduces the main circuit mass flow rate fluctuation coefficient.

[0066] Specifically, Figure 2 A flowchart for determining the target opening range is shown.

[0067] The process of calculating the main circuit mass flow rate fluctuation coefficient for each historical test sample based on the main circuit refrigerant mass flow rate data, establishing the correspondence between the opening control parameters of the electronic expansion valve in the jet branch and the main circuit mass flow rate fluctuation coefficient, and determining the target opening range to reduce the main circuit mass flow rate fluctuation coefficient based on the correspondence includes the following steps:

[0068] Step S31: Perform time series analysis on the refrigerant mass flow data of the main circuit within a preset time period in each historical test sample, and calculate the fluctuation amplitude and dispersion of the mass flow data within the preset time period. The corresponding main circuit mass flow fluctuation coefficient is obtained by combining the fluctuation amplitude and dispersion.

[0069] Step S32: Sort several historical test samples in ascending order according to the opening control parameter of the electronic expansion valve of the jet branch, construct a sample sequence, and extract the main loop mass flow fluctuation coefficient corresponding to each historical test sample in the sample sequence, so as to establish the correspondence between the opening control parameter of the electronic expansion valve of the jet branch and the main loop mass flow fluctuation coefficient.

[0070] Step S33: Based on the correspondence, perform trend analysis to identify the range characteristics of the main circuit mass flow fluctuation coefficient as a function of the jet branch electronic expansion valve opening control parameter. When there is a trend of the main circuit mass flow fluctuation coefficient decreasing first and then increasing, determine the jet branch electronic expansion valve opening control parameter range corresponding to the opening range with relatively low main circuit mass flow fluctuation coefficient as the target opening range.

[0071] The specific calculation method of the main circuit mass flow rate fluctuation coefficient includes: weighting the fluctuation amplitude and the dispersion according to a preset weighting coefficient to obtain the main circuit mass flow rate fluctuation coefficient; wherein, the fluctuation amplitude is used to characterize the range of change of the main circuit refrigerant mass flow rate data within a preset time period, and the dispersion is used to characterize the dispersion level of the main circuit refrigerant mass flow rate data within the preset time period.

[0072] In this embodiment of the invention, step S3 is mainly used to process and calculate multi-parameter data in historical test samples. It is a key step for quantitative analysis of multi-parameter data collection. The data processing algorithm is used to explore the intrinsic relationship between the opening control parameters of the jet branch electronic expansion valve and the mass flow fluctuation of the main circuit.

[0073] In step S31, time-series analysis is performed on the main loop refrigerant mass flow rate data within a preset time period in each historical test sample. Specifically, time series analysis methods can be used to process the continuously collected mass flow rate data, such as segmenting the data based on a sliding window and extracting statistical features from the data within each time period. Further, the maximum and minimum values ​​of the mass flow rate data within the preset time period can be calculated using extreme value extraction methods to obtain the fluctuation amplitude. Simultaneously, statistical analysis methods (such as standard deviation or variance calculation) can be used to quantify the dispersion of the mass flow rate data. Subsequently, a weighted fusion algorithm is used to combine and calculate the fluctuation amplitude and dispersion to obtain the main loop mass flow rate fluctuation coefficient, which comprehensively characterizes the mass flow rate fluctuation characteristics.

[0074] In step S32, several historical test samples are sorted from smallest to largest according to the opening control parameters of the electronic expansion valve in the jet branch. The sample sequence can be constructed using a sorting algorithm (such as quicksort or other conventional sorting methods). Based on this, the sorted opening control parameters are correlated with the corresponding main loop mass flow fluctuation coefficients to form an ordered set of data pairs. In this way, a mapping relationship can be established between the opening control parameters of the electronic expansion valve in the jet branch and the main loop mass flow fluctuation coefficient. This mapping relationship can essentially be represented as a curve showing the relationship between the fluctuation coefficient and the opening control parameters.

[0075] In step S33, trend analysis is performed on the relationship curve based on the above mapping relationship. Specifically, curve fitting methods or trend recognition algorithms can be used to process the data. For example, polynomial fitting, piecewise linear fitting, or discrete point-based trend judgment methods can be used to identify the trend of the fluctuation coefficient changing with the opening control parameter. When it is identified that the fluctuation coefficient first decreases and then increases with the increase of the opening control parameter, the trough region of the fluctuation coefficient can be determined by the extreme value detection algorithm or the interval search method, and the opening control parameter interval of the jet branch electronic expansion valve corresponding to the trough region can be determined as the target opening interval.

[0076] In addition to using a weighted combination of fluctuation amplitude and dispersion, other data processing methods can be used to calculate the fluctuation coefficient of the main circuit mass flow rate. For example, calculation can be based solely on the standard deviation, or the fluctuation degree can be characterized by indicators such as range and root mean square deviation. Alternatively, the fluctuation characteristic value can be calculated after normalizing the mass flow rate data, as long as it can reflect the fluctuation degree of the refrigerant mass flow rate in the main circuit.

[0077] In the weighted combination calculation, the allocation of preset weight coefficients can be set based on different technical requirements. For example, they can be set empirically based on the sensitivity of the fluctuation amplitude and dispersion to the test results, or by statistical analysis of historical test data and using the principle of minimizing error to optimize the selection of weights. This allows the main loop mass flow fluctuation coefficient to more accurately reflect the actual fluctuation characteristics and improve the accuracy and stability of target opening interval identification.

[0078] Furthermore, the method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition also includes the following steps:

[0079] Step S4: Before the current heat exchange performance test begins, obtain the current opening control parameters of the electronic expansion valve in the jet branch, and if they are not within the target opening range, adjust them to the target opening range before performing the heat exchange performance test to reduce the fluctuation of refrigerant mass flow in the main circuit.

[0080] Specifically, Figure 3 A flowchart is shown for actively adjusting the opening control parameters.

[0081] The process of obtaining the current opening control parameters of the electronic expansion valve in the jet branch before the heat exchange performance test begins, and adjusting them to the target opening range if they are not within the target range before performing the heat exchange performance test, in order to reduce the fluctuation of refrigerant mass flow in the main loop, specifically includes the following steps:

[0082] Step S401: Before the target electric compressor performs the current heat exchange performance test, obtain the current control parameters of the electronic expansion valve opening of the jet branch;

[0083] Step S402: Determine whether the current opening control parameter of the electronic expansion valve of the jet branch is within the target opening range. If so, perform a heat exchange performance test.

[0084] Step S403: If not, adjust the opening control parameters of the current jet branch electronic expansion valve to bring it into the target opening range before performing the heat exchange performance test, so as to reduce the fluctuation of the refrigerant mass flow rate in the main circuit and improve the accuracy of the heat exchange performance test.

[0085] In this embodiment of the invention, step S4 is a control step that actively adjusts the opening control parameters of the electronic expansion valve of the jet branch based on the analysis results of step S3. Its essence is to judge and correct the existing control parameters before the current heat exchange performance test begins, so as to make them meet the target opening range requirements, thereby achieving pre-control of the refrigerant mass flow fluctuation in the main circuit before the test is executed, forming a closed-loop adjustment process.

[0086] In step S401, before the target electric compressor performs the current heat exchange performance test, the current control parameters for the opening degree of the electronic expansion valve in the jet branch are acquired. Specifically, this can be obtained by reading the pre-set control command for the opening degree of the electronic expansion valve in the jet branch from the controller, or by retrieving the current control parameter value to be executed through the data interface of the test system. This process can be achieved through data communication between the controller and the data acquisition system, such as reading the corresponding control parameters via CAN communication or an industrial bus, which is a conventional data reading technique in existing control systems.

[0087] In step S402, it is determined whether the current opening control parameter of the jet branch electronic expansion valve is within the target opening range. Specifically, this can be achieved by comparing the current opening control parameter with the upper and lower limits of the target opening range, i.e., determining whether the current opening control parameter is within the range. This determination process can be executed by the controller or the host computer software, implemented through simple range determination logic, and belongs to conventional data judgment and logic control methods.

[0088] In step S403, when the current opening control parameter of the jet branch electronic expansion valve is not within the target opening range, it is adjusted to bring it into the target opening range. Specifically, the controller can generate a new opening control command based on the target opening range and send a control signal to the jet branch electronic expansion valve, thereby driving the electronic expansion valve to move within the target opening range. The adjustment can be achieved by directly setting the target opening value or by a gradual approximation method (e.g., step adjustment or closed-loop control adjustment). This process is essentially a conventional control method for electronic expansion valves (see the relevant description in step S2), adjusting the valve opening by the controller outputting an opening control signal (such as a step pulse or opening command). After the adjustment is completed, the current heat exchange performance test is performed to ensure that the test is conducted under optimized control parameter conditions.

[0089] By coordinating steps S401 to S403 above, the opening control parameters of the electronic expansion valve in the jet branch can be corrected before the test begins, ensuring that they are within the target opening range. This reduces the fluctuation of the refrigerant mass flow rate in the main circuit at the source and prevents the fluctuation from worsening due to unreasonable opening control parameters during the test.

[0090] Overall, this invention addresses the problem in existing technologies where the refrigerant mass flow rate in the main circuit fluctuates under low-temperature heating conditions, and is typically corrected through post-test compensation. It proposes a pre-emptive adjustment method based on historical data analysis. By exploring the correspondence between the opening control parameters of the electronic expansion valve in the jet branch and the main circuit mass flow rate fluctuation coefficient, and by proactively adjusting the opening control parameters before the test begins to bring them into the target opening range, the problem that would normally require post-test compensation is shifted to pre-test optimization control.

[0091] Therefore, this invention effectively addresses the technical problems raised in the aforementioned core research points, namely, the mass flow rate fluctuation caused by the superposition of suction pulsation, jet coupling, and flash evaporation effects under low-temperature heating conditions. Through the technical solution of this invention, the fluctuation of the refrigerant mass flow rate in the main circuit can be reduced, thereby reducing the compensation amplitude required in subsequent data processing and the errors introduced therefrom, and improving the accuracy and stability of heat exchange performance test results.

[0092] In terms of application prospects, this invention can be widely used in the performance testing and calibration of electric compressors in the thermal management system of new energy vehicles, especially suitable for the testing and optimization of jet-induced enthalpy-enhanced electric compressors under low-temperature heating conditions. Furthermore, the technical concept of this invention can also be extended to other scenarios involving multi-parameter coupled testing. By combining historical data analysis with pre-test parameter adjustment, the stability of the testing process and the accuracy of the results can be improved, demonstrating significant engineering application value.

[0093] It should be understood that this method can also be applied to test scenarios for other electric compressors with jet regulation structures.

[0094] Furthermore, Figure 4 An application architecture diagram of the system provided in an embodiment of the present invention is shown.

[0095] In another preferred embodiment of the present invention, an electric compressor heat exchange performance testing system based on multi-parameter acquisition includes:

[0096] The sample screening module 100 is used to retrieve a preset historical test database and select several historical test samples corresponding to the current test condition when the target electric compressor is under preset coupling conditions for heat exchange performance testing. The target electric compressor is a jet enthalpy-increasing electric compressor.

[0097] The preset coupling condition is a low-temperature heating condition, and under this condition, the electric compressor is in the jet branch open state.

[0098] Furthermore, the electric compressor heat exchange performance testing system based on multi-parameter acquisition also includes:

[0099] The data extraction module 200 is used to extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample.

[0100] Furthermore, the electric compressor heat exchange performance testing system based on multi-parameter acquisition also includes:

[0101] The relationship building module 300 is used to calculate the main circuit mass flow fluctuation coefficient of each historical test sample based on the main circuit refrigerant mass flow data, and to establish the correspondence between the opening control parameters of the electronic expansion valve of the jet branch and the main circuit mass flow fluctuation coefficient. Based on the correspondence, the target opening range that reduces the main circuit mass flow fluctuation coefficient is determined.

[0102] Furthermore, the electric compressor heat exchange performance testing system based on multi-parameter acquisition also includes:

[0103] The control and adjustment module 400 is used to acquire the current opening control parameters of the electronic expansion valve of the jet branch before the start of the current heat exchange performance test, and adjust them to the target opening range before performing the heat exchange performance test if they are not within the target opening range, so as to reduce the fluctuation of refrigerant mass flow rate in the main circuit.

[0104] It should be understood that although the steps in the flowcharts of the various embodiments of the present invention are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the various embodiments may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0105] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0106] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0107] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

[0108] 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, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition, characterized in that, The method includes: S1. When the target electric compressor is under a preset coupling condition for heat exchange performance testing, retrieve the preset historical test database and select a number of historical test samples that correspond to the current test condition. S2. Extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample. S3. Based on the refrigerant mass flow rate data of the main circuit, calculate the main circuit mass flow rate fluctuation coefficient of each historical test sample, and establish the correspondence between the opening control parameter of the electronic expansion valve of the jet branch and the main circuit mass flow rate fluctuation coefficient. Based on the correspondence, determine the target opening range that reduces the main circuit mass flow rate fluctuation coefficient. S4. Before the current heat exchange performance test begins, obtain the current opening control parameters of the electronic expansion valve in the jet branch, and if they are not within the target opening range, adjust them to the target opening range before performing the heat exchange performance test to reduce the fluctuation of refrigerant mass flow in the main circuit.

2. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 1, characterized in that, The target electric compressor is a jet-induced enthalpy-increasing electric compressor.

3. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 1, characterized in that, The preset coupling condition is a low-temperature heating condition, and under this condition, the electric compressor is in the jet branch open state.

4. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 1, characterized in that, The phrase "corresponding to the current test conditions" means that the historical test samples and the current heat exchange performance test are the same as or within a preset error range in at least one or more of the following: ambient temperature, compressor operating parameters, and heat load conditions.

5. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 1, characterized in that, Step S3 specifically includes: Time series analysis is performed on the refrigerant mass flow data of the main circuit within a preset time period in each historical test sample, and the fluctuation amplitude and dispersion of the mass flow data within the preset time period are calculated based on the mass flow data. The corresponding main circuit mass flow fluctuation coefficient is obtained by combining the fluctuation amplitude and dispersion. Several historical test samples were sorted from small to large according to the opening control parameter of the electronic expansion valve of the jet branch, and a sample sequence was constructed. The main loop mass flow fluctuation coefficient corresponding to each historical test sample in the sample sequence was extracted to establish the correspondence between the opening control parameter of the electronic expansion valve of the jet branch and the main loop mass flow fluctuation coefficient. Based on the correspondence, trend analysis is performed to identify the range characteristics of the main circuit mass flow fluctuation coefficient as a function of the jet branch electronic expansion valve opening control parameter. When there is a trend of the main circuit mass flow fluctuation coefficient first decreasing and then increasing, the range of jet branch electronic expansion valve opening control parameters corresponding to the opening range with relatively low main circuit mass flow fluctuation coefficient is determined as the target opening range.

6. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 5, characterized in that, The specific calculation method of the main circuit mass flow rate fluctuation coefficient includes: weighting the fluctuation amplitude and the dispersion according to a preset weighting coefficient to obtain the main circuit mass flow rate fluctuation coefficient; wherein, the fluctuation amplitude is used to characterize the range of change of the main circuit refrigerant mass flow rate data within a preset time period, and the dispersion is used to characterize the dispersion level of the main circuit refrigerant mass flow rate data within the preset time period.

7. The method for testing the heat exchange performance of an electric compressor based on multi-parameter acquisition according to claim 1, characterized in that, Step S4 includes: Before conducting the current heat exchange performance test on the target electric compressor, obtain the current jet branch electronic expansion valve opening control parameters; Determine whether the current opening control parameter of the electronic expansion valve in the jet branch is within the target opening range. If so, perform a heat exchange performance test. If not, the opening control parameters of the current jet branch electronic expansion valve are adjusted to bring it into the target opening range before performing the heat exchange performance test, so as to reduce the fluctuation of the refrigerant mass flow rate in the main circuit and improve the accuracy of the heat exchange performance test.

8. A test system for the heat exchange performance of an electric compressor based on multi-parameter acquisition, characterized in that, The system includes: The sample screening module is used to retrieve a preset historical test database and screen a number of historical test samples corresponding to the current test conditions when the target electric compressor is under preset coupling conditions for heat exchange performance testing. The data extraction module is used to extract the corresponding jet branch electronic expansion valve opening control parameters and main circuit refrigerant mass flow data from each historical test sample. The relationship building module is used to calculate the main circuit mass flow fluctuation coefficient of each historical test sample based on the main circuit refrigerant mass flow data, and to establish the correspondence between the opening control parameters of the electronic expansion valve of the jet branch and the main circuit mass flow fluctuation coefficient. Based on the correspondence, the target opening range that reduces the main circuit mass flow fluctuation coefficient is determined. The control and adjustment module is used to obtain the current opening control parameters of the electronic expansion valve of the jet branch before the start of the current heat exchange performance test, and adjust them to the target opening range before performing the heat exchange performance test if they are not within the target opening range, so as to reduce the fluctuation of refrigerant mass flow in the main circuit.

9. The electric compressor heat exchange performance testing system based on multi-parameter acquisition according to claim 8, characterized in that, The target electric compressor is a jet-induced enthalpy-increasing electric compressor.

10. The electric compressor heat exchange performance testing system based on multi-parameter acquisition according to claim 8, characterized in that, The preset coupling condition is a low-temperature heating condition, and under this condition, the electric compressor is in the jet branch open state.

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