A photovoltaic module IV power test system and test method

Abstract

This invention discloses a photovoltaic module IV power testing system and method, relating to the field of photovoltaic module testing technology. The method includes the following steps: collecting voltage, current, and power values ​​during the photovoltaic module IV scanning process; extracting continuous sampling points according to a preset voltage increment; calculating the power change amplitude, power change direction, and duration between adjacent continuous sampling points; and generating a dynamic change trajectory based on the calculation results. This invention adaptively adjusts the voltage advance interval and sampling density based on dynamic response characteristics to obtain continuous power change information. It also determines a stable peak region by combining the continuous power peak displacement state, and uses the power increase amplitude, power decrease amplitude, and dwell length to determine the maximum power point, improving the accuracy of maximum power point identification and enhancing the accuracy, stability, and repeatability of photovoltaic module IV power test results, while also improving test reliability under complex operating conditions.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic module testing technology, and specifically to a photovoltaic module IV power testing system and testing method. Background Technology

[0002] Photovoltaic module IV (inductively coupled plasma) power testing is a crucial testing technology in the solar energy industry for evaluating the power generation performance and quality of photovoltaic modules. Based on the current-voltage (IV) characteristic curves of photovoltaic modules under specific light intensity, temperature, and environmental conditions, it measures and analyzes key electrical performance parameters of the module, from short-circuit current and open-circuit voltage to the current and voltage at the maximum power point (MPP) and output power, thereby generating complete IV curves and power characteristic data. The test results accurately reflect the photovoltaic module's photoelectric conversion capability, output stability, manufacturing consistency, and potential defects, providing reliable data support for photovoltaic module manufacturing, factory quality inspection, product grading, system installation and acceptance, operation and maintenance, and performance degradation assessment in the solar energy industry. Simultaneously, it improves the power generation efficiency, operational reliability, and full lifecycle management level of photovoltaic power generation systems.

[0003] Existing technologies have the following shortcomings: During the IV scanning process of photovoltaic modules, due to the module's own junction capacitance, parasitic parameters, and dynamic response characteristics, as well as the influence of factors such as light fluctuations, module temperature changes, sampling timing errors, scanning rate, sampling density, and the response speed of the testing equipment, the IV data collected during the test may exhibit dynamic deviations. Especially near the maximum power point, the power change curve is relatively flat, and the power values ​​corresponding to adjacent sampling points are very close. Limited sampling density and data processing algorithms can easily cause errors in locating the maximum power point. When the module experiences partial shading, cell mismatch, or bypass diode conduction, the power curve may also show multiple local peaks, further increasing the difficulty of identifying the true maximum power point and affecting the accuracy, stability, and repeatability of the IV power test results.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a photovoltaic module IV power testing system and method to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a photovoltaic module IV power testing method, comprising the following steps: The system collects voltage, current, and power values ​​during the IV scan of photovoltaic modules, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction, and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. Based on the dynamic trajectory, the power change interval is divided according to the power change direction corresponding to the continuous sampling points. When the power change direction changes repeatedly for a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response characteristics. The duration of the corresponding power change range is calculated based on the dynamic response characteristics. The duration is compared with a preset range threshold. When the duration is greater than the preset range threshold, the voltage propagation interval in the corresponding power change range is reduced. When the duration is not greater than the preset range threshold, the preset voltage propagation interval is restored and the sampling density in the corresponding power change range is increased to obtain continuous power change information. Based on the continuous power change information, extract the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak. When the continuous power peak continues to displace within a preset range, delay the locking of the corresponding continuous power peak position and continue to execute the IV scan process until the continuous power peak stops displacing, and determine the stable peak region. For the stable peak region, the corresponding continuous power change information is re-extracted. Based on the comparison of power increase rate, power decrease rate and dwell length, the position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process.

[0007] Preferably, the steps for generating the dynamically changing trajectory are as follows: The voltage, current and power values ​​of the photovoltaic module are gradually acquired during the IV scan process according to the preset voltage increment, and a continuous sampling sequence is formed by establishing a continuous sampling sequence including voltage, current, power values ​​and scan sequence numbers. Based on the continuous sampling sequence, the power change relationship between adjacent continuous sampling points is obtained, and the corresponding power change amplitude, power change direction and change duration are calculated. The change duration is recorded according to the scanning range that is continuously maintained in the same power change direction. By combining the power change amplitude, power change direction and change duration, the continuous change relationship corresponding to each continuous sampling point is established, and they are uniformly arranged according to the scanning order to form a dynamic change trajectory. As the photovoltaic module IV scanning process continues, the voltage, current, power, power change amplitude, power change direction, and change duration corresponding to the newly added continuous sampling points are continuously added to the dynamic change trajectory, generating a dynamic change trajectory covering all continuous sampling points.

[0008] Preferably, the dynamic response feature acquisition process is as follows: Read the continuous sampling points arranged in the scanning order in the dynamic change trajectory, divide the power change interval according to the power change direction corresponding to the continuous sampling points, and keep each power change interval arranged in the scanning order. Based on the power change interval, continuously record the number of times the power change direction changes. When the number of direction changes reaches the preset number, re-divide the corresponding power change interval and redetermine the start and end positions of the corresponding power change interval. For the redefined power change intervals, the duration, frequency, and transition density are extracted, and the duration, frequency, and transition density are kept to correspond one-to-one with the corresponding power change intervals to obtain the dynamic response characteristics of the corresponding power change intervals.

[0009] Preferably, the dynamic response feature is a continuous change description composed of the continuous span, change frequency and transition density corresponding to the redefined power change interval. Specifically, the continuous span records the range of continuous sampling points covered by the corresponding power change interval, the change frequency is recorded according to the number of times the direction changes and the distribution of continuous sampling points, and the transition density is recorded according to the distribution of the positions where the power change direction changes. Together, they constitute the dynamic response feature of the corresponding power change interval.

[0010] Preferably, the process for obtaining continuous power variation information is as follows: The dynamic response characteristics corresponding to each power change range are obtained, and the continuous span of the corresponding power change range is extracted. The continuous span is compared with a preset span threshold to determine the scanning processing status of the corresponding power change range. The voltage propulsion interval is adjusted according to the comparison results for the corresponding power change range. When the continuous span is greater than the preset span threshold, the voltage propulsion interval is reduced, and when the continuous span is not greater than the preset span threshold, the preset voltage propulsion interval is restored. Based on the adjusted voltage advance interval, the continuous sampling points of the corresponding power change range are reacquired, and the sampling density of the corresponding power change range is adjusted synchronously so that the continuous sampling points are arranged continuously in the scanning order. Based on the adjusted continuous sampling points, the continuous change relationship between adjacent continuous sampling points is re-established, and the corresponding power change amplitude, power change direction and change duration are recorded to obtain the continuous power change information of the corresponding power change interval.

[0011] Preferably, continuous sampling points for the corresponding power change range are reacquired according to the adjusted voltage advance interval, and the sampling density for the corresponding power change range is adjusted synchronously. Specifically, when the voltage advance interval decreases, the voltage change range between adjacent continuous sampling points is reduced synchronously, and the sampling density within the corresponding power change range is increased by increasing the number of continuous sampling points.

[0012] Preferably, the steps for determining the stable peak region are as follows: Read the power values ​​corresponding to the continuous sampling points arranged in the scanning order in the continuous power change information, extract the continuous power peak value, and establish the correspondence between the continuous power peak value and the continuous power change information; Based on the position change records corresponding to the continuous power peak, the displacement amplitude, displacement direction and dwell length are extracted, and the displacement amplitude, displacement direction and dwell length are kept correlated with the corresponding continuous power peak. The position locking conditions are established based on the displacement amplitude, displacement direction and dwell length. When the continuous power peak continuously shifts within the preset range, the position locking of the corresponding continuous power peak is delayed, and the photovoltaic module IV scanning process continues. As the photovoltaic module IV scanning process continues, the position change record corresponding to the continuous power peak is updated, and the starting position and ending position of the stable range are determined when the continuous power peak stops displacing. All continuous sampling points between the start and end positions of the stable range are defined as the stable peak region, and the correspondence between the stable peak region and the corresponding continuous power peak is maintained.

[0013] Preferably, the displacement amplitude, displacement direction, and dwell length are extracted based on the position change records corresponding to the continuous power peaks. Specifically, the displacement amplitude is represented by the range of position change between the positions corresponding to the continuous power peaks obtained from two consecutive records. The displacement direction is recorded based on the position change generated by the position corresponding to the continuous power peaks along the scanning advance direction or along the opposite direction of the scanning advance. The dwell length is recorded by the number of consecutive sampling points or the corresponding scanning range where the continuous power peaks remain within the same position range.

[0014] Preferably, the steps for determining the maximum power point are as follows: The continuous power change information corresponding to the stable peak region is re-extracted, and all continuous sampling points are rearranged according to the scanning order corresponding to the continuous sampling points to form a continuous power change record inside the stable peak region. Based on the re-extracted continuous power change information, establish the correspondence between the power increase rate, the power decrease rate, and the dwell length, and keep the power increase rate, the power decrease rate, and the dwell length corresponding to the same continuous sampling point; A continuous comparison relationship is established by using the power increase rate, power decrease rate, and dwell length to form the power change rate of corresponding continuous sampling points and determine the dwell state of corresponding continuous sampling points; After the continuous comparison is completed, the continuous sampling points that meet the requirements of continuous dwell length reaching the preset length and power change amplitude being lower than the preset threshold are selected, and the corresponding continuous position range is determined as the target position. The target location is used as the corresponding location of the maximum power point to determine the maximum power point during the IV scan of the photovoltaic module, and the correspondence between the maximum power point and the stable peak area is maintained.

[0015] A photovoltaic module IV power testing system includes a dynamic trajectory construction module, a response feature extraction module, an adaptive scanning module, a peak stability determination module, and a maximum power point identification module. The dynamic trajectory construction module collects voltage, current and power values ​​during the IV scan of the photovoltaic module, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. The response feature extraction module, based on the dynamic change trajectory, divides the power change interval according to the power change direction corresponding to the continuous sampling points. When the power change direction changes continuously and repeatedly to a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response features. The adaptive scanning module calculates the duration of the corresponding power change range based on the dynamic response characteristics, compares the duration with a preset range threshold, reduces the voltage advance interval in the corresponding power change range when the duration is greater than the preset range threshold, restores the preset voltage advance interval when the duration is not greater than the preset range threshold, and increases the sampling density in the corresponding power change range to obtain continuous power change information. The peak stability determination module extracts the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak based on the continuous power change information. When the continuous power peak continues to displace within a preset range, the position of the corresponding continuous power peak is locked for a delay, and the IV scan process continues to be executed until the continuous power peak stops displacing, thus determining the stable peak region. The maximum power point identification module re-extracts the corresponding continuous power change information for the stable peak region, and compares the power increase rate, power decrease rate, and dwell length. The position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process.

[0016] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention constructs a dynamic trajectory and extracts dynamic response features, and adaptively adjusts the voltage advance interval and sampling density based on the continuous span. This allows the scanning process to dynamically change the sampling rhythm according to the changing state of different power change intervals, reducing the problem of incomplete power change information near the maximum power point when using a fixed scanning method. This results in obtaining more continuous power change information, improving the data integrity in the maximum power point location process, and enhancing the accuracy, stability, and repeatability of the photovoltaic module IV power test results.

[0017] This invention continuously tracks the power peak value change state by utilizing the displacement amplitude, displacement direction, and dwell length corresponding to the continuous power peak value. After the continuous power peak value stops displacing, a stable peak value region is determined. The maximum power point is determined by combining the power increase amplitude, power decrease amplitude, and dwell length. This allows the maximum power point to be established on the basis of continuous change process and stable distribution state, reducing the impact of local peak values ​​on the identification of the maximum power point, improving the reliability of the maximum power point identification under complex operating conditions, and enhancing the consistency of photovoltaic module IV power test results. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0019] Figure 1 This is a flowchart of a photovoltaic module IV power testing method according to the present invention.

[0020] Figure 2 This is a schematic diagram of a photovoltaic module IV power testing system according to the present invention. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0022] This invention provides, for example Figure 1 The photovoltaic module IV power test method shown includes the following steps: The system collects voltage, current, and power values ​​during the IV scan of photovoltaic modules, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction, and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. During the IV scan of photovoltaic modules, to ensure continuous acquisition of the changes in the output power of the photovoltaic modules, the voltage, current, and power values ​​are first continuously acquired throughout the scan, and the correspondence between continuous sampling points is established. Based on this, the dynamic change trajectory is obtained, providing a continuous data foundation for subsequent division of power change intervals. The specific steps are as follows: The photovoltaic module IV scanning process is initiated. The output voltage of the photovoltaic module is gradually changed according to the preset voltage advancement direction. At each preset voltage increment position, the corresponding voltage value, current value and power value are acquired simultaneously. Each set of corresponding data is used to establish a continuous sampling point. Each continuous sampling point includes at least the corresponding voltage value, current value, power value and scanning sequence number. All continuous sampling points are arranged in the voltage advancement order to form a continuous sampling sequence.

[0023] Adjacent consecutive sampling points maintain the same preset voltage increment. Each consecutive sampling point corresponds to a unique scanning position and maintains a continuous correlation with the previous and subsequent consecutive sampling points. This ensures that all consecutive sampling points in the entire IV scanning process are continuously distributed along the voltage advancement direction, thereby completely recording the output state corresponding to each scanning position during the photovoltaic module IV scanning process. At the same time, it ensures that any subsequent consecutive sampling point can trace the scanning relationship corresponding to its adjacent consecutive sampling points, providing a unified data foundation for subsequent continuous power change analysis.

[0024] Using a continuous sampling sequence as the continuously changing object, the power value corresponding to the next continuous sampling point is read sequentially from the first continuous sampling point and compared with the power value corresponding to the previous continuous sampling point to obtain the power change relationship between any two adjacent continuous sampling points. The power change amplitude is represented by the change in power values ​​between adjacent continuous sampling points, reflecting the degree of power value change between adjacent scan positions. The power change direction is recorded according to the trend of power value change between adjacent continuous sampling points. When the power value corresponding to the next continuous sampling point is higher than the power value corresponding to the previous continuous sampling point, it is recorded as the power growth direction; when the power value of the next continuous sampling point is higher than the power value of the previous continuous sampling point, it is recorded as the power growth direction. When the power value corresponding to a subsequent sampling point is lower than the power value corresponding to the previous consecutive sampling point, it is recorded as the power attenuation direction. When the power values ​​corresponding to adjacent consecutive sampling points are consistent, it is recorded as the power holding direction. The duration of change is used to record the scanning range in which the same power change direction is continuously maintained, and it is accumulated according to the number of consecutive sampling points. When the power change direction is consistent, the duration of change continues to increase. When the power change direction changes, the current duration of change ends the recording, and a new duration of change is established. This ensures that each consecutive sampling point in the entire continuous sampling sequence has a corresponding power change amplitude, power change direction, and duration of change.

[0025] A continuous correspondence is established around the power change amplitude, power change direction, and change duration corresponding to the continuous sampling points. The continuous sampling points are uniformly arranged according to the original scanning order to keep the change information corresponding to each continuous sampling point connected. Among them, the correspondence between voltage, current, and power values ​​is not only retained between adjacent continuous sampling points, but also the corresponding power change relationship and change duration are further recorded. As the number of continuous sampling points continues to increase, the newly acquired power change amplitude, power change direction, and change duration are sequentially added to the corresponding scanning positions. The continuous change relationship between continuous sampling points is gradually expanded to a dynamic change trajectory covering the entire IV scanning process.

[0026] The dynamic change trajectory is a continuous change record consisting of the voltage value, current value, power value, power change amplitude, power change direction, and change duration of each continuous sampling point in the scanning sequence. It completely preserves the evolution relationship of power change state throughout the entire IV scan process. It can not only record the distribution position corresponding to power growth, power decay, and power holding state, but also record the transition position, continuous holding range, and change continuation process between each change state. Thus, the power change state throughout the scanning process is expressed in a continuous correlation, rather than just retaining the independent power data corresponding to a single sampling position.

[0027] As the IV scanning process of the photovoltaic module continues, subsequent continuous sampling points are continuously added to the dynamic change trajectory according to the scanning sequence, maintaining a continuous correspondence with existing continuous sampling points. For each new continuous sampling point, corresponding voltage, current, power, power change amplitude, power change direction, and change duration are simultaneously added, causing the coverage of the dynamic change trajectory to continuously expand along the scanning direction until the entire IV scanning process is completed. Ultimately, a dynamic change trajectory covering all continuous sampling points is obtained. This dynamic change trajectory completely contains the continuous correspondence between the voltage, current, power, power change amplitude, power change direction, and change duration of the continuous sampling points throughout the scanning process, maintaining the data in a continuous arrangement according to the scanning sequence. This allows for direct acquisition of the continuous power change state and process for any scanning interval from the dynamic change trajectory, providing a continuous and complete data source for subsequent power change interval division, dynamic response feature extraction, and voltage advance interval adjustment.

[0028] Based on the dynamic trajectory, the power change interval is divided according to the power change direction corresponding to the continuous sampling points. When the power change direction changes repeatedly for a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response characteristics. The dynamic trajectory continuously records the power change states and their evolution relationships at consecutive sampling points during the IV scan of the photovoltaic module, providing a continuous data foundation for further identifying the distribution patterns of power change states within the scan range. Therefore, based on the dynamic trajectory, power change intervals are divided, and corresponding dynamic response features are extracted, enabling subsequent differentiated processing around different power change states. The specific steps are as follows: The system reads all consecutive sampling points arranged in the scanning order along the dynamic trajectory, maintaining the correlation between the power change directions of each consecutive sampling point. Using the first consecutive sampling point as the starting position of the initial power change interval, it reads the power change direction corresponding to each subsequent consecutive sampling point along the dynamic trajectory. When the power change directions of adjacent consecutive sampling points remain consistent, the current consecutive sampling point continues to be included in the current power change interval, thus continuously extending the range of consecutive sampling points covered by the current power change interval.

[0029] When the power change direction corresponding to adjacent consecutive sampling points changes, the previous consecutive sampling point corresponding to the position where the power change direction changes is taken as the end position of the current power change interval, and the consecutive sampling point corresponding to the position where the power change direction changes is taken as the start position of the next power change interval. The subsequent division is performed along the dynamic change trajectory, so that the entire dynamic change trajectory is divided into multiple power change intervals arranged continuously in the scanning order.

[0030] Each power change interval corresponds to a continuous and consistent power change direction. Different power change intervals are connected end to end. The continuous sampling points covered by each power change interval do not overlap or have any omissions. This transforms the continuous change state in the dynamic change trajectory from the continuous sampling point level to the continuous power change interval level, providing a continuous interval basis for subsequent identification of the power change state within the local scanning range.

[0031] After each power change interval is established, the positions where the power change direction switches between adjacent power change intervals are continuously recorded. The number of times the power change direction changes from power increase to power decrease and vice versa, according to the scanning order, is continuously counted. Each direction change is recorded as one direction change count, which is continuously accumulated along the dynamic change trajectory. When the number of continuously recorded direction changes reaches a preset number, it is determined that a continuously changing power change state has occurred within the corresponding scanning range. The original power change interval boundaries are no longer maintained; instead, the continuous sampling points corresponding to the continuous direction changes are collectively divided into a new power change interval. The start and end positions of the corresponding power change interval are redefined, ensuring that all continuous sampling points corresponding to the continuous direction changes belong to the newly divided power change interval. Simultaneously, the newly divided power change intervals are still arranged continuously according to the scanning order.

[0032] After the re-division is completed, the power change directions that continuously alternate within the original power change interval are uniformly summarized into the new power change interval. Different re-divided power change intervals still maintain continuous boundary relationships. Each re-divided power change interval corresponds to a unique range of continuous sampling points, so that the change state corresponding to the continuous and repeated changes in the power change direction can be concentrated in the same power change interval, and the positional relationship and change process of the continuous evolution of the power change state within the corresponding scanning range are completely preserved.

[0033] For each redefined power change interval, the duration, frequency of change, and inflection density are extracted, ensuring that each of these three pieces of information corresponds to the same power change interval. The duration is recorded using the range of continuous sampling points covered by the corresponding power change interval. Recording begins at the continuous sampling point corresponding to the start of the interval and continues until the end, thus obtaining the duration of the corresponding power change interval. The frequency of change is represented by the number of direction changes recorded within the corresponding power change interval and the distribution of continuous sampling points. When the number of direction changes occurs consecutively, the frequency of change increases synchronously; when the number of direction changes stops increasing, the frequency of change remains at its current state, ensuring that the frequency of change fully reflects the continuous change of power change direction within the corresponding power change interval. The inflection density is recorded using the distribution of the positions where the power change direction changes within the corresponding power change interval. When the direction change positions are continuously distributed between adjacent continuous sampling points, the inflection density records the continuous distribution; when the direction change positions are scattered between different continuous sampling points, the inflection density records the scattered distribution, thus fully recording the distribution relationship of direction change positions within the corresponding power change interval.

[0034] The duration, frequency of change, and transition density each maintain a one-to-one correspondence with the corresponding power change interval, and together constitute the dynamic response characteristics of the corresponding power change interval. The dynamic response characteristics are a continuous change description composed of the duration, frequency of change, and transition density of the redefined power change interval. It not only continuously records the range of power change state along the scanning direction, the direction switching state, and the distribution of transition positions, but also fully expresses the continuous evolution relationship of the power change state within the corresponding power change interval. This allows different power change intervals to be distinguished using the dynamic response characteristics, and provides a continuous, complete, and unified basis for subsequent adjustments to the voltage advance interval and sampling density of the corresponding power change interval.

[0035] The duration of the corresponding power change range is calculated based on the dynamic response characteristics. The duration is compared with a preset range threshold. When the duration is greater than the preset range threshold, the voltage propagation interval in the corresponding power change range is reduced. When the duration is not greater than the preset range threshold, the preset voltage propagation interval is restored and the sampling density in the corresponding power change range is increased to obtain continuous power change information. Dynamic response characteristics can reflect the continuous range, direction, and transition distribution of power changes within different power variation intervals, providing a basis for adjusting the scanning accuracy during the IV scanning process of photovoltaic modules. After obtaining the dynamic response characteristics, the voltage advance interval and sampling density during the scanning process are adjusted according to the continuous span corresponding to different power variation intervals, enabling the scanning process to adapt to different power variation states and obtain continuous power change information. The specific steps are as follows: Read the dynamic response characteristics corresponding to each power change interval, and obtain the continuous span of the corresponding power change interval from the dynamic response characteristics. The continuous span is used to represent the continuous sampling range covered by the corresponding power change interval. It can be recorded by the number of continuous sampling points or represented by the voltage range covered by the corresponding power change interval.

[0036] When acquiring the continuous span, the starting continuous sampling point corresponding to each power change interval is used as the recording starting point, and statistics are continuously collected along the scanning sequence until the end of the corresponding power change interval, so that each power change interval has a unique corresponding continuous span. The continuous span corresponding to each power change interval maintains a one-to-one correlation with the dynamic response characteristics, so that the change frequency, transition density and continuous span in the dynamic response characteristics jointly describe the power change state within the corresponding power change interval. Among them, the preset span threshold is used to distinguish the scanning processing state corresponding to different power change intervals. The preset span threshold can be set according to the continuous change range that can be recorded during the photovoltaic module IV scanning process. When the continuous span reaches the preset span threshold, it means that the scanning accuracy of the corresponding power change interval needs to be adjusted. When the continuous span does not reach the preset span threshold, it means that the corresponding power change interval continues to maintain the basic scanning state, thereby establishing a correspondence between the continuous span and the scanning adjustment method.

[0037] The duration of each power variation interval is compared with a preset span threshold, and the voltage advance interval adjustment method for the corresponding power variation interval is determined based on the comparison results. When the duration exceeds the preset span threshold, the voltage advance interval corresponding to the current power variation interval is reduced, thereby decreasing the voltage variation range between adjacent consecutive sampling points. New consecutive sampling points within the power variation interval are then acquired according to the adjusted voltage advance interval. The voltage advance interval represents the voltage variation between adjacent consecutive sampling points. The preset voltage advance interval is the basic scanning interval set at the start of the photovoltaic module IV scan. The adjusted voltage advance interval varies according to a preset adjustment range based on the preset voltage advance interval.

[0038] When the sustained span is no greater than a preset span threshold, the voltage advance interval within the corresponding power change range is restored to the preset voltage advance interval, allowing the power change range to continue advancing according to the basic scan rhythm. By using different voltage advance intervals for different sustained spans, a more refined voltage advance method is used in areas where the power change range extends continuously, while the basic advance method is restored in areas where the change range does not reach the preset span threshold, thus keeping the voltage advance status dynamically adjusted throughout the entire IV scan process.

[0039] As the voltage advance interval changes, the distribution of continuous sampling points within each power variation range is adjusted synchronously, and corresponding continuous sampling points are reacquired according to the adjusted voltage advance interval. When the voltage advance interval decreases, the voltage variation range between adjacent continuous sampling points shrinks synchronously, increasing the number of continuous sampling points within the same power variation range, thus increasing the number of samples per unit voltage range. When the voltage advance interval returns to the preset voltage advance interval, the original continuous sampling point acquisition rhythm is maintained, and voltage, current, and power values ​​are continuously acquired within the corresponding power variation range according to the preset voltage advance interval. The sampling density represents the distribution of continuous sampling points within a unit scan range, and it is adjusted synchronously with the number of continuous sampling points. When the corresponding power variation range requires improved scanning accuracy, the sampling density is increased by increasing the number of continuous sampling points; when the corresponding power variation range returns to the basic scanning state, the preset sampling density is maintained.

[0040] After adjusting the voltage advance interval and changing the sampling density, the continuous sampling points within each power change range are still arranged continuously according to the scanning order, and the correspondence with the dynamic response characteristics is maintained, so that the adjusted scanning data can reflect a more continuous output change process under different power change states.

[0041] Based on the adjusted voltage advance interval and the changed sampling density, continuous sampling points corresponding to each power change interval are reacquired. The voltage, current, and power values ​​corresponding to the newly added continuous sampling points are added to the corresponding power change intervals according to the original scanning order, thus re-establishing a continuous change relationship between adjacent continuous sampling points. Furthermore, the power change amplitude, power change direction, and change duration corresponding to adjacent continuous sampling points are recorded, ensuring that the adjusted scanning data maintains a continuous correlation with the original dynamic change trajectory. Continuous power change information is formed from the change information corresponding to each continuous sampling point. Specifically, the continuous power change information is a continuous record of the voltage, current, power, power change amplitude, power change direction, and change duration corresponding to all continuous sampling points within the corresponding power change interval after the voltage advance interval and sampling density adjustment. It continuously reflects the change process of the power value within the corresponding power change interval as the scan progresses, while preserving the positional relationship, change direction relationship, and change duration relationship between different continuous sampling points. The continuous power change information corresponding to each power change interval is recorded independently and associated with the corresponding dynamic response characteristics, so that the change state corresponding to the continuous power peak can be extracted based on the continuous power change information, and the stable peak region can be further determined.

[0042] In this way, the scanning accuracy during the photovoltaic module IV scanning process can be adjusted according to the dynamic response state corresponding to the power change range, so that the continuous power change information can completely cover the output change process under different power change states, providing a continuous and complete data foundation for subsequent maximum power point identification.

[0043] Based on the continuous power change information, extract the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak. When the continuous power peak continues to displace within a preset range, delay the locking of the corresponding continuous power peak position and continue to execute the IV scan process until the continuous power peak stops displacing, and determine the stable peak region. Continuous power variation information can continuously reflect the changes in power values ​​within each power variation interval as the scan progresses, providing a continuous basis for identifying the power peak value near the maximum power point. By continuously recording the position changes of the power peak using continuous power variation information and adjusting the position locking timing in conjunction with the peak change status, a stable peak region can be established based on the continuous variation process, providing a unified data source for subsequent determination of the maximum power point. The specific steps are as follows: Read the power values ​​corresponding to the continuous sampling points arranged in the scanning order in the continuous power change information, and extract the continuous power peak value based on the change relationship formed by the continuous increase and continuous decrease of the power value along the scanning direction. When the power values ​​corresponding to multiple adjacent continuous sampling points remain consistent or close, the corresponding continuous sampling points are taken as the same continuous power peak value, so that the continuous power peak value can cover the continuous change range corresponding to the actual power peak value.

[0044] Each continuous power peak corresponds to a unique position record. This position can be represented by the corresponding voltage position or by the scan position corresponding to the continuous sampling point, maintaining a one-to-one correspondence between the continuous power peak and the continuous power change information. As new continuous sampling points continuously add continuous power change information, the position of the continuous power peak is updated synchronously, enabling the continuous power peaks formed in different scanning stages to establish a continuous association according to the scanning sequence. This provides a continuous positional basis for subsequent extraction of displacement amplitude, displacement direction, and dwell length.

[0045] A continuous position record is established around the positional changes corresponding to the continuous power peak, and the displacement amplitude, displacement direction, and dwell length corresponding to the continuous power peak are extracted respectively. The displacement amplitude is represented by the range of positional changes between the positions corresponding to the continuous power peak obtained from two consecutive records. This range of positional changes can be represented by the range of positional changes corresponding to the corresponding voltage position or the range of positional changes between corresponding consecutive sampling points. The displacement direction is recorded based on the positional changes generated by the position corresponding to the continuous power peak along the scanning advance direction or along the opposite direction of the scanning advance, so that different positional changes are described in a consistent direction. The dwell length is recorded by the number of consecutive sampling points where the continuous power peak exists continuously within the same positional range or the corresponding scanning range. When the continuous power peak is continuously maintained within the same positional range, the dwell length continuously increases. When the position of the continuous power peak changes, a new dwell length record is established for the corresponding position.

[0046] The displacement amplitude, displacement direction, and dwell length together constitute the positional change state of the continuous power peak and maintain a correlation with the corresponding continuous power peak.

[0047] A position locking condition is established based on the position change state of the continuous power peak, and a preset range is set to limit the range of allowable position changes of the continuous power peak. The preset range can be represented by the corresponding voltage position change range or by the coverage range of continuous sampling points. It is used to determine whether the continuous power peak is still in the allowable change state.

[0048] When the displacement amplitude corresponding to the continuous power peak remains within the preset range, and the displacement direction continues to change continuously or alternately, it indicates that the continuous power peak is still in the process of position change. At this time, the position lock of the corresponding continuous power peak is delayed, and the current continuous power peak is not taken as the final peak position, while the IV scan process continues. During the delayed position lock period, new continuous sampling points are continuously acquired, and the continuous power change information is updated using the new continuous sampling points. The displacement amplitude, displacement direction, and dwell length corresponding to the continuous power peak are synchronously re-extracted, so that the position change state of the continuous power peak is continuously updated as the scan progresses, while the position lock state remains delayed until the continuous power peak meets the stop displacement condition.

[0049] The IV scan process is continuously executed, and the position change record corresponding to the continuous power peak is continuously updated. When the position corresponding to the continuous power peak obtained by continuous recording remains consistent, no new displacement direction is formed during continuous recording, and the corresponding dwell length continues to extend continuously, the continuous power peak is determined to stop displacement. If a new displacement amplitude or a new displacement direction is generated again during continuous recording, the continuous power peak is kept in a continuous displacement state, and the IV scan process continues.

[0050] After the continuous power peak stops displacement, the continuous sampling point corresponding to the first stable position is taken as the starting position of the stable range, and the continuous sampling point corresponding to the end of the stable state of the continuous power peak is taken as the ending position of the stable range. All continuous sampling points between the starting position and the ending position are uniformly determined as the stable peak area, so that the stable peak area covers the entire continuous change range after the continuous power peak stops displacement, and the correspondence between the stable peak area and the corresponding continuous power peak is maintained.

[0051] After the stable peak region is formed, the corresponding continuous power change information is still associated, and the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak are retained. This ensures that the stable peak region not only includes the stable position after the continuous power peak stops displacing, but also fully retains the continuous change process of the continuous power peak gradually transitioning from continuous displacement to a stable state.

[0052] The stable peak region represents the continuous power change region formed by the continuous sampling points corresponding to the continuous power peak after the continuous power peak stops displacing. Its boundary is jointly defined by the continuous sampling points corresponding to the start position and the continuous sampling points corresponding to the end position of the stable range. The region contains the voltage value, current value, power value, power change amplitude, power change direction, displacement amplitude, displacement direction, and dwell length corresponding to the continuous sampling points. It maintains the scanning order and continuous correlation between each continuous sampling point, so that the stable peak region can completely reflect the location range and formation process of the final stable distribution of the continuous power peak. This provides a continuous, complete, and unified data foundation for extracting the power growth amplitude, power decay amplitude, and dwell length based on the stable peak region and determining the maximum power point.

[0053] For the stable peak region, the corresponding continuous power change information is re-extracted. Based on the comparison of power growth rate, power decay rate and dwell length, the position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process. Once the stable peak region is formed, it retains the complete process of the continuous power peak gradually transitioning from a changing state to a stable state, providing a continuous data foundation for further determination of the maximum power point. The continuous power change information is reorganized around the stable peak region, and a continuous comparative relationship is established by combining the power increase rate, power decrease rate, and dwell time. This ensures that the maximum power point is established based on the combined effect of the continuous changing state and the sustained stable state within the stable peak region. The specific steps are as follows: The corresponding continuous power change information is re-extracted around the stable peak region, maintaining a one-to-one correspondence between the stable peak region and the continuous power change information. When re-extracting the corresponding continuous power change information, only the voltage, current, power, power change amplitude, power change direction, and duration of change corresponding to all continuous sampling points within the coverage area of ​​the stable peak region are retained. Simultaneously, all continuous sampling points are rearranged according to their scanning order, re-establishing a continuous correlation between adjacent continuous sampling points, forming a continuous power change record confined within the stable peak region.

[0054] The reorganized continuous power change information still maintains the sequential connection between continuous sampling points. The positional relationship, change relationship, and continuity relationship of the continuous sampling points remain consistent. The boundary of the stable peak region serves as the starting and ending range of the reorganized continuous power change information. Continuous sampling points outside the boundary do not participate in the current maximum power point determination process. This allows the re-extracted continuous power change information to fully reflect the continuous change state of the power value along the scanning direction within the stable peak region, providing a unified data source for establishing the subsequent power increase amplitude, power attenuation amplitude, and dwell length.

[0055] Based on the re-extracted continuous power change information, a correspondence is established between power growth rate, power decay rate, and dwell length. The power growth rate is recorded as the range of continuous power change from the starting continuous sampling point to the current continuous sampling point, ensuring a continuous growth state before the power value reaches its peak. The power decay rate is recorded as the range of continuous power change from the current continuous sampling point to the end of the power decline, ensuring a complete record of the continuous change state after the power value leaves the peak position. The dwell length represents the continuous range within which the power value of a continuous sampling point remains within the same power change range. It can be represented by the number of continuous sampling points or by the corresponding scan range. When the power value of a continuous sampling point remains within the same change range, the dwell length continuously extends; when the power value of a continuous sampling point changes, a new dwell length record is established. The power growth rate, power decay rate, and dwell length always correspond to the same continuous sampling point and together describe the continuous power change state at the corresponding position within the stable peak region.

[0056] A continuous comparison relationship is established based on the power increase rate, power decrease rate, and dwell length, and the target location is selected according to a unified comparison order. First, the dwell length corresponding to the continuous sampling points is associated to determine the continuous state in which the corresponding continuous sampling points maintain a stable distribution. Then, the corresponding power increase rate and power decrease rate are associated to ensure that the continuous change state of the continuous sampling points before and after entering the peak position remains completely consistent. Finally, the power change rate of the corresponding continuous sampling points is formed by the power increase rate and power decrease rate together. The power change rate is used to represent the overall continuous change range of the power value corresponding to the continuous sampling point from the increase state to the decrease state, and maintains a one-to-one correspondence with the corresponding continuous sampling points.

[0057] The preset length is used to limit the range of continuous sampling points that need to maintain a stable distribution. When the dwell length reaches the preset length, it means that the corresponding continuous sampling points have formed a continuous stable state. The preset threshold is used to limit the range of power changes that can be maintained within the stable peak area. When the power change amplitude is within the range of the preset threshold, it means that the corresponding continuous sampling points maintain a continuous and stable power output state. This establishes a unified comparison relationship between the dwell state and the power change state.

[0058] Based on the continuous comparison results, continuous sampling points that meet the target conditions are gradually selected. When the continuous dwell length corresponding to the continuous sampling point reaches the preset length and the corresponding power change amplitude is lower than the preset threshold, the current continuous sampling point is determined as the target position. If the continuous dwell length does not reach the preset length, the corresponding continuous sampling point continues to participate in the continuous comparison, and the dwell length is updated again as new continuous sampling points are added. If the power change amplitude does not meet the preset threshold limit, the corresponding continuous sampling point continues to participate in subsequent continuous comparisons, so that the power increase amplitude, power decrease amplitude, and dwell length corresponding to the continuous sampling point are updated synchronously.

[0059] When multiple consecutive sampling points within a stable peak region continuously meet the conditions of a continuous dwell length reaching a preset length and a power change amplitude below a preset threshold, the continuous location range covered by the corresponding multiple consecutive sampling points is uniformly determined as the same target location, so that the continuous sampling points that continuously meet the conditions maintain a continuous and stable distribution state, and avoid the formation of multiple independent target locations within the stable peak region.

[0060] The maximum power point during the IV scan of the photovoltaic module is determined around the target location, maintaining the correspondence between the maximum power point and the stable peak region. The maximum power point can be represented by the position of a continuous sampling point corresponding to the target location, or by the voltage position corresponding to the target location, ensuring that the maximum power point always corresponds to a position that remains stably distributed within the stable peak region.

[0061] When the target location covers multiple consecutive sampling points, the continuous location range formed by the corresponding consecutive sampling points is uniformly regarded as the location corresponding to the same maximum power point. The corresponding continuous power change information, power increase rate, power decrease rate, and dwell length are retained, ensuring that the maximum power point not only corresponds to the finally determined location but also fully preserves the continuous change process that led to that location. The finally determined maximum power point is always based on the continuous power change state within a stable peak region. Its formation process is fully correlated with the re-extracted continuous power change information, power increase rate, power decrease rate, and dwell length, thereby completing the determination of the maximum power point during the photovoltaic module IV scan process and providing a continuous, complete, and consistent data foundation for the photovoltaic module output power assessment.

[0062] This invention constructs a dynamic trajectory and extracts dynamic response features, and adaptively adjusts the voltage advance interval and sampling density based on the continuous span. This allows the scanning process to dynamically change the sampling rhythm according to the changing state of different power change intervals, reducing the problem of incomplete power change information near the maximum power point when using a fixed scanning method. This results in obtaining more continuous power change information, improving the data integrity in the maximum power point location process, and enhancing the accuracy, stability, and repeatability of the photovoltaic module IV power test results.

[0063] This invention continuously tracks the power peak value change state by utilizing the displacement amplitude, displacement direction, and dwell length corresponding to the continuous power peak value. After the continuous power peak value stops displacing, a stable peak value region is determined. The maximum power point is determined by combining the power increase amplitude, power decrease amplitude, and dwell length. This allows the maximum power point to be established on the basis of continuous change process and stable distribution state, reducing the impact of local peak values ​​on the identification of the maximum power point, improving the reliability of the maximum power point identification under complex operating conditions, and enhancing the consistency of photovoltaic module IV power test results.

[0064] This invention provides, for example Figure 2 The photovoltaic module IV power testing system shown includes a dynamic trajectory construction module, a response feature extraction module, an adaptive scanning module, a peak stability determination module, and a maximum power point identification module. The dynamic trajectory construction module collects voltage, current and power values ​​during the IV scan of the photovoltaic module, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. The response feature extraction module, based on the dynamic change trajectory, divides the power change interval according to the power change direction corresponding to the continuous sampling points. When the power change direction changes continuously and repeatedly to a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response features. The adaptive scanning module calculates the duration of the corresponding power change range based on the dynamic response characteristics, compares the duration with a preset range threshold, reduces the voltage advance interval in the corresponding power change range when the duration is greater than the preset range threshold, restores the preset voltage advance interval when the duration is not greater than the preset range threshold, and increases the sampling density in the corresponding power change range to obtain continuous power change information. The peak stability determination module extracts the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak based on the continuous power change information. When the continuous power peak continues to displace within a preset range, the position of the corresponding continuous power peak is locked for a delay, and the IV scan process continues to be executed until the continuous power peak stops displacing, thus determining the stable peak region. The maximum power point identification module re-extracts the corresponding continuous power change information for the stable peak region, and compares the power increase rate, power decrease rate, and dwell length. The position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process.

[0065] The present invention provides a photovoltaic module IV power testing method, which is implemented by the above-mentioned photovoltaic module IV power testing system. For details of the specific method and process of the photovoltaic module IV power testing system, please refer to the above-mentioned embodiment of the photovoltaic module IV power testing method, which will not be repeated here.

[0066] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for testing the IV power of a photovoltaic module, characterized in that, Includes the following steps: The system collects voltage, current, and power values ​​during the IV scan of photovoltaic modules, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction, and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. Based on the dynamic trajectory, the power change interval is divided according to the power change direction corresponding to the continuous sampling points. When the power change direction changes repeatedly for a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response characteristics. The duration of the corresponding power change range is calculated based on the dynamic response characteristics. The duration is compared with a preset range threshold. When the duration is greater than the preset range threshold, the voltage propagation interval in the corresponding power change range is reduced. When the duration is not greater than the preset range threshold, the preset voltage propagation interval is restored and the sampling density in the corresponding power change range is increased to obtain continuous power change information. Based on the continuous power change information, extract the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak. When the continuous power peak continues to displace within a preset range, delay the locking of the corresponding continuous power peak position and continue to execute the IV scan process until the continuous power peak stops displacing, and determine the stable peak region. For the stable peak region, the corresponding continuous power change information is re-extracted. Based on the comparison of power increase rate, power decrease rate and dwell length, the position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process.

2. The photovoltaic module IV power testing method according to claim 1, characterized in that, The steps for generating a dynamically changing trajectory are as follows: The voltage, current and power values ​​of the photovoltaic module are gradually acquired during the IV scan process according to the preset voltage increment, and a continuous sampling sequence is formed by establishing a continuous sampling sequence including voltage, current, power values ​​and scan sequence numbers. Based on the continuous sampling sequence, the power change relationship between adjacent continuous sampling points is obtained, and the corresponding power change amplitude, power change direction and change duration are calculated. By combining the power change amplitude, power change direction and change duration, the continuous change relationship corresponding to each continuous sampling point is established, and they are uniformly arranged according to the scanning order to form a dynamic change trajectory. As the photovoltaic module IV scanning process continues, the voltage, current, power, power change amplitude, power change direction, and change duration corresponding to the newly added continuous sampling points are continuously added to the dynamic change trajectory, generating a dynamic change trajectory covering all continuous sampling points.

3. The photovoltaic module IV power testing method according to claim 2, characterized in that, The process of obtaining dynamic response features is as follows: Read the continuous sampling points arranged in the scanning order in the dynamic change trajectory, divide the power change interval according to the power change direction corresponding to the continuous sampling points, and keep each power change interval arranged in the scanning order. Based on the power change interval, continuously record the number of times the power change direction changes. When the number of direction changes reaches the preset number, re-divide the corresponding power change interval and redetermine the start and end positions of the corresponding power change interval. For the redefined power change intervals, the duration, frequency, and transition density are extracted, and the duration, frequency, and transition density are kept to correspond one-to-one with the corresponding power change intervals to obtain the dynamic response characteristics of the corresponding power change intervals.

4. The photovoltaic module IV power testing method according to claim 3, characterized in that, The dynamic response characteristics are a continuous change description consisting of the continuous span, change frequency, and transition density corresponding to the redefined power change interval. Specifically, the continuous span records the range of continuous sampling points covered by the corresponding power change interval, the change frequency is recorded based on the number of times the direction changes and the distribution of continuous sampling points, and the transition density is recorded based on the distribution of the positions where the power change direction changes. Together, they constitute the dynamic response characteristics of the corresponding power change interval.

5. The photovoltaic module IV power testing method according to claim 3, characterized in that, The process of obtaining continuous power variation information is as follows: The dynamic response characteristics corresponding to each power change range are obtained, and the continuous span of the corresponding power change range is extracted. The continuous span is compared with a preset span threshold to determine the scanning processing status of the corresponding power change range. The voltage propulsion interval is adjusted according to the comparison results for the corresponding power change range. When the continuous span is greater than the preset span threshold, the voltage propulsion interval is reduced, and when the continuous span is not greater than the preset span threshold, the preset voltage propulsion interval is restored. Based on the adjusted voltage advance interval, the continuous sampling points of the corresponding power change range are reacquired, and the sampling density of the corresponding power change range is adjusted synchronously so that the continuous sampling points are arranged continuously in the scanning order. Based on the adjusted continuous sampling points, the continuous change relationship between adjacent continuous sampling points is re-established, and the corresponding power change amplitude, power change direction and change duration are recorded to obtain the continuous power change information of the corresponding power change interval.

6. The photovoltaic module IV power testing method according to claim 5, characterized in that, Based on the adjusted voltage advance interval, continuous sampling points for the corresponding power change range are reacquired, and the sampling density for the corresponding power change range is adjusted synchronously. Specifically, when the voltage advance interval decreases, the voltage change range between adjacent continuous sampling points is reduced synchronously, and the sampling density within the corresponding power change range is increased by increasing the number of continuous sampling points.

7. The photovoltaic module IV power testing method according to claim 5, characterized in that, The steps for determining the stable peak region are as follows: Read the power values ​​corresponding to the continuous sampling points arranged in the scanning order in the continuous power change information, extract the continuous power peak value, and establish the correspondence between the continuous power peak value and the continuous power change information; Based on the position change records corresponding to the continuous power peak, the displacement amplitude, displacement direction and dwell length are extracted, and the displacement amplitude, displacement direction and dwell length are kept correlated with the corresponding continuous power peak. The position locking conditions are established based on the displacement amplitude, displacement direction and dwell length. When the continuous power peak continuously shifts within the preset range, the position locking of the corresponding continuous power peak is delayed, and the photovoltaic module IV scanning process continues. As the photovoltaic module IV scanning process continues, the position change record corresponding to the continuous power peak is updated, and the starting position and ending position of the stable range are determined when the continuous power peak stops displacing. All continuous sampling points between the start and end positions of the stable range are defined as the stable peak region, and the correspondence between the stable peak region and the corresponding continuous power peak is maintained.

8. The photovoltaic module IV power testing method according to claim 7, characterized in that, The displacement amplitude, displacement direction, and dwell length are extracted based on the position change records corresponding to the continuous power peaks. Specifically, the displacement amplitude is represented by the range of position change between the positions corresponding to the continuous power peaks obtained from two consecutive records. The displacement direction is recorded based on the position change generated by the position corresponding to the continuous power peaks along the scanning advance direction or along the opposite direction of the scanning advance. The dwell length is recorded by the number of consecutive sampling points or the corresponding scanning range where the continuous power peaks are held within the same position range.

9. A photovoltaic module IV power testing method according to claim 7, characterized in that, The steps for determining the maximum power point are as follows: The continuous power change information corresponding to the stable peak region is re-extracted, and all continuous sampling points are rearranged according to the scanning order corresponding to the continuous sampling points to form a continuous power change record inside the stable peak region. Based on the re-extracted continuous power change information, establish the correspondence between the power increase rate, the power decrease rate, and the dwell length, and keep the power increase rate, the power decrease rate, and the dwell length corresponding to the same continuous sampling point; A continuous comparison relationship is established by using the power increase rate, power decrease rate, and dwell length to form the power change rate of corresponding continuous sampling points and determine the dwell state of corresponding continuous sampling points; After the continuous comparison is completed, the continuous sampling points that meet the requirements of continuous dwell length reaching the preset length and power change amplitude being lower than the preset threshold are selected, and the corresponding continuous position range is determined as the target position. The target location is used as the corresponding location of the maximum power point to determine the maximum power point during the IV scan of the photovoltaic module, and the correspondence between the maximum power point and the stable peak area is maintained.

10. A photovoltaic module IV power testing system, used to implement the photovoltaic module IV power testing method according to any one of claims 1-9, characterized in that, It includes a dynamic trajectory construction module, a response feature extraction module, an adaptive scanning module, a peak stability determination module, and a maximum power point identification module: The dynamic trajectory construction module collects voltage, current and power values ​​during the IV scan of the photovoltaic module, extracts continuous sampling points according to the preset voltage increment, calculates the power change amplitude, power change direction and change duration between adjacent continuous sampling points, and generates a dynamic change trajectory based on the calculation results. The response feature extraction module, based on the dynamic change trajectory, divides the power change interval according to the power change direction corresponding to the continuous sampling points. When the power change direction changes continuously and repeatedly to a preset number of times, the corresponding power change interval is re-divided, and the continuous span, change frequency and turning density corresponding to the re-divided power change interval are extracted to obtain the dynamic response features. The adaptive scanning module calculates the duration of the corresponding power change range based on the dynamic response characteristics, compares the duration with a preset range threshold, reduces the voltage advance interval in the corresponding power change range when the duration is greater than the preset range threshold, restores the preset voltage advance interval when the duration is not greater than the preset range threshold, and increases the sampling density in the corresponding power change range to obtain continuous power change information. The peak stability determination module extracts the displacement amplitude, displacement direction and dwell length corresponding to the continuous power peak based on the continuous power change information. When the continuous power peak continues to displace within a preset range, the position of the corresponding continuous power peak is locked for a delay, and the IV scan process continues to be executed until the continuous power peak stops displacing, thus determining the stable peak region. The maximum power point identification module re-extracts the corresponding continuous power change information for the stable peak region, and compares the power increase rate, power decrease rate, and dwell length. The position where the continuous dwell length reaches the preset length and the power change rate is lower than the preset threshold is determined as the maximum power point in the photovoltaic module IV scan process.

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