Method and system for evaluating protection effect of surge protection device of photovoltaic system

Abstract

The invention discloses a method and a system for evaluating the protection effect of a surge protection device of a photovoltaic system. The method comprises the following steps: acquiring working parameters of the surge protection device and corresponding environment parameters in real time; calculating each performance index of the surge protection device according to the working parameters of the surge protection device; comparing each performance index of the surge protection device with the performance index under the standard condition, and calculating the performance change; according to the performance change and the change of the environmental parameters, carrying out environmental sensitivity analysis, and calculating a sensitivity coefficient; according to each performance index of the surge protection device and an actually required performance index, calculating a fitness score; based on the fitness score and the sensitivity coefficient, obtaining an environment fitness comprehensive score; and evaluating the protection effect of the surge protection device according to the comprehensive score of the environment adaptation degree. Influences of various performance factors and environmental factors are considered, and the protection effect of the surge protection device in a real environment is accurately reflected.

Description

Technical Field

[0001] The present invention belongs to the technical field of lightning strike safety protection for photovoltaic power generation systems, and relates to a method and system for evaluating the protection effect of surge protectors in photovoltaic systems. Background Art

[0002] In recent years, photovoltaic power generation technology has developed rapidly and been widely applied globally due to its clean, renewable, and environmentally friendly characteristics. As an important part of new energy power generation, the safe operation of photovoltaic systems has attracted increasing attention. Since photovoltaic systems are usually installed in outdoor environments and directly exposed to various natural conditions, they are extremely vulnerable to overvoltage hazards such as lightning strikes, which pose a serious threat to the stable operation of photovoltaic systems.

[0003] Surge protectors (SPDs) are key protection devices in photovoltaic systems. Their main function is to limit transient overvoltages and overcurrents caused by overvoltages such as lightning to protect photovoltaic systems and their related devices from damage. However, with the continuous increase in the application and complexity of photovoltaic systems, traditional surge protector evaluation technologies have gradually revealed certain limitations and cannot meet the urgent needs of current photovoltaic system safety protection.

[0004] Currently, surge protector evaluation methods are usually based on a single lightning waveform (such as the 8 / 20 μs waveform) or standard impulse current. These test conditions often cannot fully simulate the variable factors such as surge waveforms, amplitudes, and frequencies in actual lightning strike processes, resulting in the inability to accurately reflect the protection effect of surge protectors in real lightning strike environments and thus unable to provide reliable guarantees for the safety protection of photovoltaic systems. Summary of the Invention

[0005] The purpose of the present invention is to solve the technical problem that the existing surge protector evaluation methods cannot fully simulate the variable factors such as surge waveforms, amplitudes, and frequencies in actual lightning strike processes, resulting in the inability to accurately reflect the protection effect of surge protectors in real lightning strike environments, and to provide a method and system for evaluating the protection effect of surge protectors in photovoltaic systems.

[0006] To achieve the above object, the present invention adopts the following technical solutions: In the first aspect of the present invention, a method for evaluating the protection effect of a surge protector in a photovoltaic system is provided, including the following steps: Real-time collect the working parameters of the surge protector and the corresponding environmental parameters; Calculate each performance index of the surge protector according to the working parameters of the surge protector; Compare each performance index of the surge protector with the performance index under standard conditions, and calculate the performance change; according to the performance change and the change of environmental parameters, conduct environmental sensitivity analysis and calculate the sensitivity coefficient; Calculate the fitness score according to each performance index of the surge protector and the required performance index; Based on the fitness score and the sensitivity coefficient, obtain the comprehensive environmental fitness score; Evaluate the protection effect of the surge protector according to the comprehensive environmental fitness score.

[0007] Further, the working parameters include current, voltage, response time and frequency; the environmental parameters include temperature, humidity and lightning strike frequency.

[0008] Further, the performance indexes include maximum absorption energy, residual voltage, response time, frequency response range and temperature tolerance.

[0009] Further, the calculation formula for the maximum absorption energy is:

[0010] Wherein, is the voltage across the surge protector, is the current passing through the surge protector; is the duration of the surge event.

[0011] Further, the calculation formula for the residual voltage is:

[0012] Wherein, is the peak voltage of the surge; is the clamping voltage of the surge protector for the surge.

[0013] Further, the calculation of the performance change is specifically:

[0014] Wherein, is the performance change rate, represents the performance index of the surge protector; represents the performance index under standard conditions.

[0015] Further, the calculation of the sensitivity coefficient is specifically:

[0016] Wherein, is the amount of performance change, is the amount of change in environmental parameters.

[0017] Further, the calculation of the fitness score is specifically:

[0018] Among them, represents the adaptation degree score; represents the weight of the item performance index; represents the actual performance index value; represents the value of the required performance index.

[0019] Furthermore, the comprehensive environmental adaptation degree score is:

[0020] Among them, is the sensitivity coefficient; is the adaptation degree score; and are both weight coefficients.

[0021] The second aspect of the present invention provides a system for evaluating the protection effect of a surge protector for a photovoltaic system, including: a parameter acquisition module that collects the operating parameters of the surge protector and the corresponding environmental parameters in real time; a performance index calculation module that calculates each performance index of the surge protector according to the operating parameters of the surge protector; a sensitivity coefficient calculation module that compares each performance index of the surge protector with the performance index under standard conditions to calculate the performance change; according to the performance change and the change of the environmental parameters, conducts environmental sensitivity analysis and calculates the sensitivity coefficient; an adaptation degree score calculation module that calculates the adaptation degree score according to each performance index of the surge protector and the actually required performance index; a comprehensive score calculation module that obtains the comprehensive environmental adaptation degree score based on the adaptation degree score and the sensitivity coefficient; an effect evaluation module that evaluates the protection effect of the surge protector according to the comprehensive environmental adaptation degree score.

[0022] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a method for evaluating the protection effect of a surge protector in a photovoltaic system. By collecting the working parameters of the surge protector and the corresponding environmental parameters in real time, the timeliness and accuracy of the evaluation data are ensured; in the method, multiple key performance indicators are calculated based on the working parameters of the surge protector. These indicators comprehensively reflect the protection performance of the surge protector, including its surge absorption ability, response time, stability, etc., providing a quantitative basis for comprehensively evaluating the performance of the surge protector. By comparing the performance indicators of the surge protector with those under standard conditions, calculating the performance change, and combining the change of environmental parameters for environmental sensitivity analysis, a sensitivity coefficient is obtained. This step helps to understand the performance stability of the surge protector under different environmental conditions; in the method, according to each performance indicator of the surge protector and the actually required performance indicators, an adaptation score is calculated. This score intuitively reflects the ability of the surge protector to meet the actual needs, providing clear guidance for selection and optimization. By combining the adaptation score and the sensitivity coefficient, an overall environmental adaptation score is obtained. This overall score comprehensively considers the performance stability of the surge protector and the ability to meet the actual needs, providing a scientific basis for comprehensively and objectively evaluating the protection effect of the surge protector.

[0023] Further, the working parameters include current, voltage, response time, and frequency. These parameters are the direct embodiment of the performance of the surge protector. By monitoring these parameters in real time, the working state of the surge protector can be accurately grasped, and potential performance problems can be discovered and processed in a timely manner. The specific working parameters and environmental parameters provide a quantitative basis for evaluating the protection effect of the surge protector. By comparing the actual values of these parameters with the standard values or expected values, it is possible to more accurately determine whether the performance of the surge protector meets the requirements, thereby improving the accuracy of the evaluation.

[0024] Further, the adaptation score formula provides a quantitative basis for evaluating the protection effect of the surge protector in a photovoltaic system. By calculating the ratio of the actual performance indicator value to the required performance indicator value and multiplying by the corresponding weight, the overall adaptation score of the surge protector can be intuitively obtained, thereby quantifying the quality of its protection effect. Summing up multiple performance indicators means that the evaluation process comprehensively considers multiple key performance indicators of the surge protector, such as current carrying capacity, voltage protection level, response time, etc. This comprehensive consideration method can more comprehensively reflect the overall performance of the surge protector. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention, and thus should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0026] Figure 1 It is a block diagram of the method for evaluating the protection effect of a surge protector in a photovoltaic system according to the present invention; Figure 2 It is a block diagram of the system for evaluating the protection effect of a surge protector in a photovoltaic system according to the present invention. Specific embodiments

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and marked in the drawings here can be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0029] It should be noted that: similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0030] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0031] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0032] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if the terms "set", "installed", "connected", "linked" appear, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0033] The following further describes the present invention in detail with reference to the accompanying drawings: See Figure 1 , the present invention discloses a method for evaluating the protection effect of a surge protector for a photovoltaic system, including the following steps: S1. Collect the working parameters of the surge protector and the corresponding environmental parameters in real time; the working parameters include current, voltage, response time, and frequency; the environmental parameters include temperature, humidity, and lightning strike frequency.

[0034] S2. Calculate each performance index of the surge protector according to the working parameters of the surge protector; the performance indexes include maximum absorption energy, residual voltage, response time, frequency response range, and temperature tolerance.

[0035] The calculation formula for the maximum absorption energy is:

[0036] Among them, is the voltage across the surge protector, is the current passing through the surge protector; is the duration of the surge event. Through this formula, the energy absorption ability of the surge protector in a surge event can be evaluated.

[0037] The calculation formula for the residual voltage is:

[0038] Among them, is the peak voltage of the surge; is the clamping voltage of the surge protector to the surge. The magnitude of the residual voltage directly reflects the protection ability of the surge protector to the system equipment.

[0039] Response time: It is the response speed of the surge protector to the surge, reflecting the reaction efficiency of the surge protector when the surge occurs. The shorter the response time, the faster and more timely the protection effect of the surge protector. Its calculation formula is:

[0040] Among them, The time difference from when the surge protector senses a surge to when it starts to clamp.

[0041] Frequency response range: It refers to the frequency range that the surge protector can effectively suppress. A surge protector usually not only prevents DC overvoltage but also needs to work under overvoltages of different frequencies. The calculation formula is:

[0042] Where, is the lowest frequency that the surge protector can effectively suppress; is the highest frequency that the surge protector can effectively suppress; is the frequency response range, which can be tested jointly by a signal generator and an oscilloscope to evaluate the clamping ability of the surge protector for surges of different frequencies.

[0043] Temperature tolerance: The high-temperature resistance ability of the surge protector reflects its working performance in extreme environments, especially the temperature influence it may receive during long-term use. The evaluation method is: High-temperature test: Place the surge protector in an environment with a specified temperature (such as 70°C, 85°C, etc.) and operate it for a long time, and record its performance changes.

[0044] Temperature resistance limit: Measure the maximum working time of the surge protector in a high-temperature environment. When the temperature exceeds the limit, the surge protector starts to fail or its performance decreases. The temperature resistance test can be completed through an environmental test chamber to ensure the stable and reliable operation of the surge protector under different working conditions.

[0045] S3. Compare each performance index of the surge protector with the performance index under standard conditions and calculate the performance change; specifically:

[0046] Where, is the performance change rate, represents the performance index of the surge protector; represents the performance index under standard conditions.

[0047] According to the performance change amount and the change of environmental parameters, conduct environmental sensitivity analysis and calculate the sensitivity coefficient; specifically:

[0048] Where, is the performance change amount, is the environmental parameter change amount.

[0049] S4. Calculate the adaptation score based on the various performance indicators of the surge protector and the performance indicators actually required. First, determine the environmental characteristics of the region where the photovoltaic system is located according to its installation location, such as lightning-prone areas, coastal areas, high-altitude regions, etc. This step is to understand the particularity of the environment where the photovoltaic system is located, so as to accurately match the performance requirements of the surge protector (SPD) subsequently.

[0050] Secondly, clarify the performance indicators that the SPD should possess in this region according to the environmental requirements of the photovoltaic system installation area. These performance indicators should be able to meet the special requirements of local environment for surge protection. Then, compare the test results of the SPD with these performance indicators to evaluate the applicability of the SPD, that is, whether it can play an effective protective role in the local environment.

[0051] Finally, calculate the adaptation score by comparing the matching degree between the performance of the SPD in a specific region and the local required performance. This score can intuitively reflect the adaptation degree of the SPD to the local environment and provide a scientific basis for selecting the most suitable SPD. The adaptation score is specifically:

[0052] Among them, represents the adaptation score; represents the weight of the th performance indicator; represents the actual performance indicator value; represents the value of the required performance indicator.

[0053] S5. Obtain the comprehensive environmental adaptation score based on the adaptation score and the sensitivity coefficient; calculate the comprehensive performance score of the SPD according to the adaptation score and the sensitivity coefficient.

[0054] Among them, is the sensitivity coefficient; is the adaptation score; and are both weight coefficients.

[0055] S6. Evaluate the protection effect of the surge protector according to the comprehensive environmental adaptation score. Analyze the advantages and disadvantages of the SPD in actual application according to the comprehensive score result, and put forward optimization suggestions to help users select the most suitable surge protector and optimize the configuration during actual operation.

[0056] In one embodiment of the present invention, the performance of the surge protector is tested under typical natural environmental conditions to verify its protection effect. As shown in the following table, the following indicators are tested in this embodiment:

[0057] Based on the method of the above embodiments, environmental sensitivity analysis is carried out according to the change in performance and the change in environmental parameters, and the sensitivity coefficient is calculated; specifically:

[0058] Wherein, is the change in performance, is the change in environmental parameters.

[0059] According to each performance index of the surge protector and the required performance index, the fitness score is calculated; specifically:

[0060] Wherein, represents the fitness score; represents the weight of the item performance index; represents the actual performance index value; represents the value of the required performance index.

[0061] The fitness evaluation form is as follows:

[0062] The total score close to 1 indicates that the SPD performance is highly suitable for this area.

[0063] Finally, based on the fitness score and the sensitivity coefficient, the comprehensive environmental fitness score is obtained;

[0064] Wherein, is the sensitivity coefficient; is the fitness score; and are both weight coefficients.

[0065] The method for evaluating the protection effect of a surge protector in a photovoltaic system according to the present invention ensures the accuracy and timeliness of evaluation data by collecting the operating parameters of the surge protector and the corresponding environmental parameters in real time. By calculating the performance change rate and combining it with the change of environmental parameters, environmental sensitivity analysis is carried out to obtain the sensitivity coefficient. This step helps to understand the performance stability of the surge protector under different environmental conditions and provides a basis for the selection of environmental adaptability in practical applications. The calculation formula of the fitness score takes into account the matching degree between the actual performance index and the required performance index, as well as the weights of each performance index. This step can intuitively reflect the ability of the surge protector to meet the actual needs and provides guidance for selection and optimization. By performing a weighted sum of the sensitivity coefficient and the fitness score, the comprehensive environmental fitness score is obtained. This comprehensive evaluation system takes into account both the performance stability of the surge protector and its ability to meet the actual needs, providing a scientific basis for comprehensively evaluating the protection effect of the surge protector.

[0066] An embodiment of the present invention provides a system for evaluating the protection effect of a surge protector in a photovoltaic system, including: A parameter acquisition module that collects the operating parameters of the surge protector and the corresponding environmental parameters in real time; A performance index calculation module that calculates each performance index of the surge protector according to the operating parameters of the surge protector; A sensitivity coefficient calculation module that compares each performance index of the surge protector with the performance index under standard conditions to calculate the performance change; according to the performance change and the change of environmental parameters, environmental sensitivity analysis is carried out to calculate the sensitivity coefficient; A fitness score calculation module that calculates the fitness score according to each performance index of the surge protector and the required performance index; A comprehensive score calculation module that obtains the comprehensive environmental fitness score based on the fitness score and the sensitivity coefficient; An effect evaluation module that evaluates the protection effect of the surge protector according to the comprehensive environmental fitness score.

[0067] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for evaluating the protection effect of a surge protector in a photovoltaic system, characterized in that, It includes the following steps: Collect the working parameters of the surge protector and the corresponding environmental parameters in real time; Calculate each performance index of the surge protector according to the working parameters of the surge protector; Compare each performance index of the surge protector with the performance index under standard conditions, and calculate the performance change; according to the performance change and the change of environmental parameters, conduct environmental sensitivity analysis and calculate the sensitivity coefficient; Calculate the fitness score according to each performance index of the surge protector and the actually required performance index; Obtain the comprehensive environmental fitness score based on the fitness score and the sensitivity coefficient; Evaluate the protection effect of the surge protector according to the comprehensive environmental fitness score.

2. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 1, characterized in that, The working parameters include current, voltage, response time and frequency; the environmental parameters include temperature, humidity and lightning strike frequency.

3. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 1, wherein The performance indexes include maximum absorption energy, residual voltage, response time, frequency response range and temperature tolerance.

4. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 3, characterized in that, The calculation formula for the maximum absorption energy is: Wherein, is the voltage across the surge protector, is the current passing through the surge protector; is the duration of the surge event.

5. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 3, characterized in that, The calculation formula for the remaining voltage is as follows: Among them, is the peak voltage of the surge; is the clamping voltage of the surge protector for the surge.

6. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 1, characterized in that, The calculation of the performance change is specifically: Among them, is the performance change rate, representing the performance indicators of the surge protector; represents the performance indicators under standard conditions.

7. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 1, characterized in that, The calculation of the sensitivity coefficient is specifically: Among them, is the performance change amount, is the environmental parameter transformation amount.

8. The method for evaluating the protection effect of a surge protector in a photovoltaic system according to claim 1, wherein The calculation of the fitness score is specifically: Among them, represents the fitness score; represents the weight of the th performance indicator; represents the actual value of the performance indicator; represents the value of the required performance indicator.

9. The method for evaluating the protection effect of a surge protector for a photovoltaic system according to claim 1, characterized in that, The comprehensive environmental fitness score is: Among them, is the sensitivity coefficient; is the fitness score; and are both weight coefficients.

10. A system for evaluating the protection effect of a surge protector in a photovoltaic system, based on the method for evaluating the protection effect of a surge protector in a photovoltaic system according to claim 1, characterized in that, It includes: A parameter acquisition module that collects the working parameters of the surge protector and the corresponding environmental parameters in real time; A performance index calculation module that calculates each performance index of the surge protector according to the working parameters of the surge protector; A sensitivity coefficient calculation module that compares each performance index of the surge protector with the performance index under standard conditions, calculates the performance change; according to the performance change and the change of environmental parameters, conducts environmental sensitivity analysis and calculates the sensitivity coefficient; A fitness score calculation module that calculates the fitness score according to each performance index of the surge protector and the actually required performance index; A comprehensive score calculation module that obtains the comprehensive environmental fitness score based on the fitness score and the sensitivity coefficient; An effect evaluation module that evaluates the protection effect of the surge protector according to the comprehensive environmental fitness score.

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