CN115208309A - Photovoltaic module current mismatch fault diagnosis method based on I-V characteristic curve - Google Patents
Photovoltaic module current mismatch fault diagnosis method based on I-V characteristic curve Download PDFInfo
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Abstract
The invention provides a photovoltaic module current mismatch fault diagnosis method based on an I-V characteristic curve, and belongs to the technical field of photovoltaic power generation. The fault diagnosis method comprises the steps of firstly obtaining I-V output characteristic curve data of a photovoltaic module, then carrying out smoothing processing on the I-V output characteristic curve data to eliminate abnormal data values, forming straight lines by every two adjacent points on the I-V characteristic curve after the photovoltaic module is smoothed, calculating an included angle between every two adjacent straight lines to obtain a current mismatch fault characteristic value of the photovoltaic module, and diagnosing current mismatch faults by judging the relation between the minimum value of the current mismatch fault characteristic value and a given threshold value. The method can simply and quickly diagnose the current mismatch fault by utilizing the photovoltaic module I-V characteristic curve, is suitable for the photovoltaic system with the photovoltaic module I-V scanning function, can effectively prevent the damage caused by the current mismatch fault, and is favorable for improving the reliability and the power generation efficiency of the photovoltaic system.
Description
Technical Field
The invention relates to a fault diagnosis method for a photovoltaic module, in particular to a photovoltaic module current mismatch fault diagnosis method based on an I-V characteristic curve, and belongs to the technical field of photovoltaic power generation.
Background
In the large background of the rapid increase of installed photovoltaic capacity, people are more and more aware that the operation and maintenance technology of a photovoltaic power station is important. The photovoltaic module is used as basic key equipment in a photovoltaic power generation system, and the reliable operation of the photovoltaic module directly determines the energy efficiency level and the operation profit of the system. Because the actual photovoltaic power station is applied to the scene with relatively complex terrain or environment, the photovoltaic module is easily influenced by the external environment and the operation condition to induce various defects or faults. The common faults of shadow shielding, hot spots, glass fragmentation and the like of the photovoltaic module can cause the photovoltaic module to generate current mismatch, and the concave inflection point appears on the I-V characteristic curve, so that the output power of the photovoltaic module is seriously influenced, and safety problems such as fire disasters and the like can be caused under the serious condition. Therefore, online diagnosis of the current mismatch fault of the photovoltaic module is realized, damage caused by the current mismatch fault can be effectively prevented, and the reliability and the power generation efficiency of a photovoltaic system are improved.
The literature "optical fault detection on the electronic circuits modifying and fuzzy classification system" Energy, 2017, 140:276-290. ("photovoltaic fault detection algorithm based on theoretical curve modeling and fuzzy classification system", energy, 140, pages 276-290 in 2017), a fault diagnosis method which can accurately identify faults existing in a photovoltaic module by modeling a theoretical I-V curve of the photovoltaic module and adopting fuzzy classification is provided, but the modeling process of the method is complex, and the accuracy of fault diagnosis depends on a model.
The invention patent document of China (CN 111444615A) provides a method for extracting fault characteristics based on an IV curve and diagnosing faults through a K-nearest neighbor classification algorithm, wherein the method is based on the IV curve and is based on a photovoltaic array fault diagnosis method based on the K-nearest neighbor and the IV curve, but the method depends on priori knowledge and needs a large amount of training data.
The invention patent document of China (CN 109861644A) proposes a method for diagnosing faults of a photovoltaic module by selecting a reference IV curve and comparing the reference IV curve with other IV curves, and the method depends on the selection of the reference curve, and the selection process of the reference curve is complex and the diagnosis process is time-consuming.
In summary, the following problems still exist in the prior art:
1. the photovoltaic module modeling process is complex, the parameters are difficult to identify, and the fault diagnosis result depends on the model precision;
2. prior knowledge and a large amount of training data are needed, and the algorithm is difficult to realize;
3. the discrimination method is complex and the diagnosis process is time-consuming.
Disclosure of Invention
The invention aims to overcome the problems in the prior art, and particularly provides an I-V curve-based photovoltaic module current mismatch fault diagnosis method, which can simply and conveniently diagnose the current mismatch fault of the photovoltaic module, effectively avoid the damage caused by the fault and improve the safety and reliability of the operation of a photovoltaic system.
In order to achieve the purpose, the invention provides a photovoltaic module current mismatch fault diagnosis method based on an I-V characteristic curve, wherein a photovoltaic module related to the fault diagnosis method is one of photovoltaic module strings, each photovoltaic module string is formed by connecting a plurality of photovoltaic modules with the same structure in series, each photovoltaic module string is formed by connecting three photovoltaic sub-strings with the same structure in series, each photovoltaic sub-string comprises c photovoltaic cell units and a bypass diode, and the c photovoltaic cell units are connected in series and then connected in anti-parallel with the bypass diode;
the fault diagnosis method comprises the following steps:
among n groups of data of the set G1, U 0 ＝V OC ，I 0 =0 and U n-1 ＝0，I n-1 ＝I SC Wherein V is OC Is the open circuit voltage of the photovoltaic module, I SC Is the short circuit current of the photovoltaic module;
defining the sorting current I obtained in step 1 i Smoothly sequence the current for 0 round, and rewrite as I 0i Defining the sorting current obtained after the j rounds of smoothing as a j round of smooth sorting current I ji Wherein j =1,2.. N, i =0,1.. N-1;
smoothly sequence the currents I by 0 rounds 0i Sequentially smoothing the current after the previous round of smoothing treatment according to the sequence of j =1,2.. N as a starting point, and smoothly sequencing the current I in the j round ji The assignment rule of (2) is as follows:
(1) When the sorting index i =1 to n-2,
if satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then I is ji ＝I (j-1)i ；
If not satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then, then
(2) When the sorting index I =0, then I j0 ＝I 0 ；
(3) When the sorting serial number I = n-1, then I j(n-1) ＝I n-1 ；
After the N rounds of smoothing are finished, N N rounds of smooth sequencing currents I are obtained Ni The N N smooth sequencing currents I Ni Assigning values to the set G1, and recording the assigned set G1 as a set G2, G2= [ (U) s_0 ，I s_0 )，(U s_1 ，I s_1 )，...(U s_i ，I s_i )，...，(U s_n-1 ，I s_n-1 )]Wherein, I s_i For smoothing the current, U s_i To smooth the current I s_i Corresponding smoothing voltage, U s_i ＝U i ，I s_i ＝I Ni ，i＝0，1...n-1；
step 4.1, on the plane coordinate system stated in the step 3, making a connecting line between every two adjacent data points in the n data points obtained in the step 3 to obtain n-1 straight lines in total, and recording any one straight line in the n-1 straight lines as a straight line L t The n-1 straight lines are sorted from the small direction to the large direction according to the smooth voltage to form a set G3, G3= [ L ] 1 ，L 2 ，...L t ，...，L n-1 ]Wherein t =1,2,. Cndot.n-1;
will straight line L t The left end data point of (a) is marked as a starting point, the right end data point is marked as an end point, and a straight line L is marked t Is denoted as k t Slope k t The calculation formula of (A) is as follows:
wherein, I s_t Is a straight line L t Smoothing current at the end point, I s_t-1 Is a straight line L t-1 Smoothing current at the end point, U s_t Is a straight line L t Smoothed voltage at the end point, U s_t-1 Is a straight line L t-1 A smoothed voltage at the end point;
step 4.2, calculating every two adjacent straight lines L in the set G3 according to the sequence of t =1,2 t The included angles between the two groups are n-2 included anglesLet any one of n-2 included angles be the included angle theta m M =1,2,.., n-2, will make up the included angle θ m Respectively marked as a previous straight line L m And a rear straight line L m+1 Angle of inclusion theta m The calculation formula of (A) is as follows:
wherein k is m Is a previous straight line L m Slope of (a), k m+1 Is a rear straight line L m+1 The slope of (a);
step 4.3, define X (θ) m ) Is an included angle theta m M =1,2,.., n-2, sign function X (θ) m ) The expression of (a) is:
defining a current mismatch characteristic F (theta) m ) M =1,2, n-2, characteristic value of current mismatch F (θ) m ) The calculation formula of (A) is as follows:
F(θ m )＝θ m X(θ m )
n-2 current mismatch characteristic values F (theta) are obtained through calculation m ) Taking the minimum value as the minimum current mismatch characteristic value F min ；
Step 4.4, obtaining the minimum current mismatch characteristic value F according to the step 4.3 min And a preset threshold epsilon, and carrying out current mismatch diagnosis, specifically:
if F min If the value is less than epsilon, an abnormal concave inflection point exists in the I-V characteristic curve of the photovoltaic module, and the photovoltaic module has current mismatch;
if F min And more than or equal to epsilon, the photovoltaic module has no current mismatch.
Compared with the prior art, the invention has the beneficial effects that:
1. the current mismatch fault of the photovoltaic component can be simply and quickly diagnosed;
2. no additional equipment is needed, and the model and the environmental parameters are not depended on, so that the method is economical and convenient;
3. the system can diagnose on line in real time and provide alarm for operation and maintenance personnel;
4. the photovoltaic array with the photovoltaic module I-V scanning function can be practically applied to a photovoltaic array with the photovoltaic module I-V scanning function, and the power generation efficiency and reliability of a photovoltaic system are improved.
Drawings
FIG. 1 is a schematic view of a photovoltaic module according to an embodiment of the present invention;
FIG. 2 is a flow chart of a photovoltaic module current mismatch fault diagnosis method of the present invention;
FIG. 3 is an I-V characteristic curve diagram of a photovoltaic module with abnormal points on the I-V characteristic curve;
FIG. 4 is a graph of I-V characteristics of a photovoltaic module after smoothing;
FIG. 5 is a graph of I-V characteristics of a photovoltaic module with a current mismatch fault;
FIG. 6 is a schematic diagram of a photovoltaic module current mismatch fault diagnosis method according to the present invention;
FIG. 7 is a schematic diagram of step 4 of the photovoltaic module current mismatch fault diagnosis method of the present invention when there is no current mismatch fault in the photovoltaic module;
fig. 8 is a schematic diagram of step 4 of the photovoltaic module current mismatch fault diagnosis method of the present invention when the photovoltaic module has a current mismatch fault.
Detailed Description
The invention will be further described with reference to the following specific examples and the accompanying drawings:
fig. 1 is a schematic structural diagram of a photovoltaic module in an embodiment of the present invention, and as can be seen from fig. 1, the photovoltaic module related to the fault diagnosis method is one of photovoltaic string strings, each of the photovoltaic string is formed by connecting a plurality of photovoltaic modules with the same structure in series, each of the photovoltaic modules is formed by connecting three photovoltaic sub-strings with the same structure in series, each of the photovoltaic sub-strings includes c photovoltaic cell units and a bypass diode, and the c photovoltaic cell units are connected in series and then connected in anti-parallel with the bypass diode.
In the present embodiment, c =20.
Fig. 2 is a flowchart of the photovoltaic module current mismatch fault diagnosis method of the present invention. As can be seen from the figure, the photovoltaic module current mismatch fault diagnosis method based on the I-V characteristic curve comprises the following steps:
among n groups of data of the set G1, U 0 ＝V OC ，I 0 =0 and U n-1 ＝0，I n-1 ＝I SC Wherein V is OC Is the open circuit voltage of the photovoltaic module, I SC Is the short circuit current of the photovoltaic module.
defining the sorting current I obtained in step 1 i Smoothly sequence the current for 0 round, and rewrite as I 0i Defining the sorting current obtained after the j rounds of smoothing as a j round of smooth sorting current I ji Wherein j =1,2.. N, i =0,1.. N-1;
smoothly sequence the current I with 0 round 0i Sequentially smoothing the current after the previous round of smoothing treatment according to the sequence of j =1,2.. N as a starting point, and smoothly sequencing the current I in the j round ji The assignment rule of (2) is as follows:
(1) When the sorting index i =1 to n-2,
if satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then, I ji ＝I (j-1)i ；
If not satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then, then
(2) When the sorting index I =0, then I j0 ＝I 0 ；
(3) When the sorting index I = n-1, then I j(n-1) ＝I n-1 ；
After the N rounds of smoothing are finished, N N rounds of smooth sequencing currents I are obtained Ni The N N smooth sequencing currents I Ni Assigning values to the set G1, and recording the assigned set G1 as a set G2, G2= [ (U) s_0 ，I s_0 )，(U s_1 ，I s_1 )，...(U s_i ，I s_i )，...，(U s_n-1 ，I s_n-1 )]Wherein, I s_i For smoothing the current, U s_i To smooth the current I s_i Corresponding smoothing voltage, U s_i ＝U i ，I s_i ＝I Ni ，i＝0，1...n-1。
Fig. 3 is an I-V characteristic curve diagram of a photovoltaic module I-V characteristic curve having abnormal points, where the abscissa axis is the voltage of the photovoltaic module and the ordinate axis is the current of the photovoltaic module, and data abnormality may exist in the photovoltaic module I-V data acquired by the optimizer, such as abnormal upper convex points or abnormal lower concave points, and the use of the original I-V data may affect the fault diagnosis result, so that the abnormal values in the photovoltaic module I-V characteristic curve need to be smoothed.
Fig. 4 is an I-V characteristic curve diagram after smoothing of the photovoltaic module, the abscissa axis is the voltage of the photovoltaic module, the ordinate axis is the current of the photovoltaic module, and N rounds of smoothing are performed on the abnormal values in the I-V characteristic curve of the photovoltaic module appearing in fig. 3, as can be seen from fig. 4, after N rounds of smoothing, the abnormal values on the I-V characteristic curve can be eliminated, and a smoother I-V characteristic curve can be obtained for subsequent current mismatch fault diagnosis. The number of smoothing rounds N =3 in this embodiment.
step 4.1, on the plane coordinate system stated in the step 3, making a connecting line between every two adjacent data points in the n data points obtained in the step 3 to obtain n-1 straight lines in total, and recording any one straight line in the n-1 straight lines as a straight line L t The n-1 straight lines are sorted from the small direction to the large direction according to the smooth voltage, and form a set G3, G3= [ L ] 1 ，L 2 ，...L t ，...，L n-1 ]Wherein t =1,2,. N-1;
will the straight line L t The left end data point of (2) is marked as a starting point, the right end data point is marked as an end point, and a straight line L is marked t The slope of (A) is denoted as k t Slope k t The calculation formula of (c) is:
wherein, I s_t Is a straight line L t Smoothing current at the end point, I s_t-1 Is a straight line L t-1 Smoothing current at the end point, U s_t Is a straight line L t Smoothed voltage at the end point, U s_t-1 Is a straight line L t-1 A smoothed voltage at the end point;
step 4.2, calculating every two adjacent straight lines L in the set G3 according to the order of t =1,2 t N-2 included angles are obtained, and any one of the n-2 included angles is taken as an included angle theta m M =1,2,.., n-2, will make up the included angle θ m Respectively marked as a previous straight line L m And a rear straight line L m+1 Angle of inclination theta m The calculation formula of (c) is:
wherein k is m Is a previous straight line L m Slope of (a), k m+1 Is a rear straight line L m+1 The slope of (a);
step 4.3, define X (θ) m ) At an included angle theta m M =1,2,.., n-2, sign function X (θ) m ) The expression of (c) is:
defining a current mismatch characteristic value F (theta) m ) M =1,2, n-2, characteristic value of current mismatch F (θ) m ) The calculation formula of (A) is as follows:
F(θ m )＝θ m X(θ m )
n-2 current mismatch characteristic values F (theta) are obtained through calculation m ) Taking the minimum value as the minimum current mismatch characteristic value F min ；
Step 4.4, obtaining the minimum current mismatch characteristic value F according to the step 4.3 min And a predetermined threshold epsilon, performing current mismatch diagnosis, specifically:
if F min If the value is less than epsilon, an abnormal concave inflection point exists in the I-V characteristic curve of the photovoltaic module, and the photovoltaic module has current mismatch;
if F min And E, the current mismatch does not exist in the photovoltaic module.
Fig. 5 is an I-V characteristic curve diagram of a photovoltaic module with a current mismatch fault, when the photovoltaic module has a shadow shielding, hot spot, and glass fragmentation fault, the current mismatch fault occurs in the photovoltaic module, and an I-V characteristic curve of the mismatched photovoltaic module changes from an I-V characteristic curve of a normal photovoltaic module, that is, a concave inflection point appears on the I-V characteristic curve of the mismatched photovoltaic module.
FIG. 6 is a schematic diagram of a photovoltaic module current mismatch fault diagnosis method of the present invention, in which the abscissa axis is the voltage of the photovoltaic module and the ordinate axis is the current of the photovoltaic module, and each phase is determined according to the I-V characteristic curve of the photovoltaic moduleCalculating the included angle between every two adjacent straight lines by the straight line formed by the two adjacent points, further calculating the characteristic value of current mismatch, and judging the characteristic value F of minimum current mismatch min And judging whether the current mismatch fault exists in the photovoltaic module or not according to the size relation of the given threshold epsilon.
Fig. 7 is a schematic diagram of step 4 of the photovoltaic module current mismatch fault diagnosis method of the present invention when no current mismatch fault exists in the photovoltaic module, wherein the axis of abscissa is the voltage of the photovoltaic module and the axis of ordinate is the current of the photovoltaic module, as can be seen from fig. 7, when no current loss exists in the photovoltaic module, the current mismatch characteristic value F (θ) thereof m ) Minimum value of (F) min At around 0 value, F (θ) m ) Without a significant negative jump and without exceeding a given threshold epsilon, the photovoltaic module is free from current mismatch faults.
Fig. 8 is a schematic diagram of step 4 of the photovoltaic module current mismatch fault diagnosis method of the present invention when the photovoltaic module has a current mismatch fault, taking a shadow-shielded photovoltaic module I-V characteristic curve as an example, as shown in fig. 8, when there is a current loss in the photovoltaic module, a concave inflection point appears on the I-V characteristic curve, and a coordinate of the concave inflection point on the I-V characteristic curve is set as (U) s_a ，I s_a ) Straight line L a And a straight line L a+1 The included angle between them is theta a Due to the straight line L a Slope k of a Less than straight line L a+1 Slope k of a+1 So that the included angle theta a Sign function X (theta) a ) =1, characteristic value of current mismatch F (θ) m ) A pronounced negative jump occurs at the concave inflection point of the I-V characteristic curve, and F (theta) m ) Minimum value of (F) min Is significantly less than the case where no current mismatch fault is present, at which time the minimum current mismatch characteristic value F min Less than a given threshold epsilon, the photovoltaic module has a current mismatch fault.
Claims (1)
1. A photovoltaic module current mismatch fault diagnosis method based on an I-V characteristic curve relates to a photovoltaic module which is one of photovoltaic string strings, wherein each photovoltaic string is formed by connecting a plurality of photovoltaic modules with the same structure in series, each photovoltaic module is formed by connecting three photovoltaic string with the same structure in series, each photovoltaic string comprises c photovoltaic cell units and a bypass diode, and the c photovoltaic cell units are connected in series and then are connected with the bypass diode in an anti-parallel mode;
the fault diagnosis method is characterized by comprising the following steps:
step 1, firstly, obtaining voltage-current data on an I-V output characteristic curve of a photovoltaic module through an optimizer with an I-V scanning function to obtain n groups of data, then sequencing the n groups of data from large to small according to voltage values to obtain n groups of data after sequencing, and forming the n groups of data after sequencing into a set G1, wherein G1= [ (U) is defined as 0 ，I 0 )，(U 1 ，I 1 )，...(U i ，I i )，...，(U n-1 ，I n-1 )]Wherein, U i To sequence the voltages, I i To and sequence the voltage U i Corresponding sorting current, i is a sorting serial number, and i =0,1.. N-1;
among n groups of data of the set G1, U 0 ＝V OC ，I 0 =0 and U n-1 ＝0，I n-1 ＝I SC Wherein, V OC Is the open circuit voltage of the photovoltaic module, I SC Is the short circuit current of the photovoltaic module;
step 2, enabling n sequencing voltages U in the set G1 i Is kept constant, n sorting currents I in the set G1 are sorted i Performing N rounds of smoothing treatment, wherein N is a positive integer, and the method specifically comprises the following steps:
defining the sorting current I obtained in step 1 i Smoothly sequence the current for 0 round, and rewrite as I 0i Defining the sorting current obtained after the j rounds of smoothing as a j round of smooth sorting current I ji Wherein j =1,2.. N, i =0,1.. N-1;
smoothly sequence the currents I by 0 rounds 0i As a starting point, smoothing is sequentially performed on the current after the previous round of smoothing in the sequence of j =1,2.. N, and the current I is smoothly sorted in j rounds ji The assignment rule of (2) is as follows:
(1) When the sorting index i =1 to n-2,
if satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then I is ji ＝I (j-1)i ；
If not satisfy I (j-1)(i-1) ≤I (j-1)i ≤I (j-1)(i+1) Then, then
(2) When the sorting index I =0, then I j0 ＝I 0 ；
(3) When the sorting index I = n-1, then I j(n-1) ＝I n-1 ；
After N rounds of smoothing are finished, N N rounds of smooth sequencing currents I are obtained Ni The N smooth sequencing currents I Ni Assigning values to the set G1, and recording the assigned set G1 as a set G2, G2= [ (U) s_0 ，I s_0 )，(U s_1 ，I s_1 )，...(U s_i ，I s_i )，...，(U s_n-1 ，I s_n-1 )]Wherein, I s_i For smoothing the current, U s_i To smooth the current I s_i Corresponding smoothing voltage, U s_i ＝U i ，I s_i ＝I Ni ，i＝0，1...n-1；
Step 3, smoothing the voltage U according to the n groups of data in the set G2 obtained in the step 2 s_i Is the horizontal axis to smooth the current I s_i Finding n data points corresponding to n groups of data in a plane coordinate system as a longitudinal axis, and connecting the data points into an I-V characteristic curve;
step 4, performing current mismatch diagnosis on the I-V characteristic curve obtained in the step 3, and specifically comprising the following steps:
step 4.1, on the plane coordinate system in the step 3, connecting lines are formed between every two adjacent data points in the n data points obtained in the step 3, n-1 straight lines are obtained in total, and any one straight line in the n-1 straight lines is taken as a straight line L t The n-1 straight lines are sorted from the small direction to the large direction according to the smooth voltage, and form a set G3, G3= [ L ] 1 ，L 2 ，...L t ，...，L n-1 ]Wherein t =1,2,. Cndot.n-1;
will straight line L t The left end data point of (a) is marked as a starting point, the right end data point is marked as an end point, and a straight line L is marked t The slope of (A) is denoted as k t Slope k t The calculation formula of (c) is:
wherein, I s_t Is a straight line L t Smoothing current at the end point, I s_t-1 Is a straight line L t-1 Smoothing current at the end point, U s_t Is a straight line L t Smoothed voltage at the end point, U s_t-1 Is a straight line L t-1 A smoothed voltage at the end point;
step 4.2, calculating every two adjacent straight lines L in the set G3 according to the sequence of t =1,2 t N-2 included angles are obtained, and any one of the n-2 included angles is taken as an included angle theta m M =1,2, n-2, will make up the included angle θ m Respectively marked as a previous straight line L m And a rear straight line L m+1 Angle of inclination theta m The calculation formula of (A) is as follows:
wherein k is m Is a previous straight line L m Slope of (a), k m+1 Is a rear straight line L m+1 The slope of (a);
step 4.3, define X (θ) m ) Is an included angle theta m M =1,2,.., n-2, sign function X (θ) m ) The expression of (a) is:
defining a current mismatch characteristic value F (theta) m ) M =1,2, n-2, characteristic value of current mismatch F (θ) m ) The calculation formula of (c) is:
F(θ m )＝θ m X(θ m )
n-2 current mismatch characteristic values F (theta) are obtained through calculation m ) Taking the minimum value as the minimum current mismatch characteristic value F min ；
Step 4.4, obtaining the minimum current mismatch characteristic value F according to the step 4.3 min And a preset threshold epsilon, and carrying out current mismatch diagnosis, specifically:
if F min If the value is less than epsilon, an abnormal concave inflection point exists in the I-V characteristic curve of the photovoltaic module, and the photovoltaic module has current mismatch;
if F min And more than or equal to epsilon, the photovoltaic module has no current mismatch.
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| US20160087132A1 (en) * | 2014-09-19 | 2016-03-24 | Hamad Musabeh Ahmed Saif Alteneiji | Dynamic PV Module And Method Of Manufacturing |
| CN107463742A (en) * | 2017-08-01 | 2017-12-12 | 河海大学常州校区 | A kind of modeling method for photovoltaic module exception degradation failure |
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| CN113572427A (en) * | 2021-08-31 | 2021-10-29 | 上能电气股份有限公司 | Photovoltaic I-V curve test system, test method and photovoltaic equipment |
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| CN114640304A (en) * | 2022-03-28 | 2022-06-17 | 合肥工业大学 | Photovoltaic module current mismatch fault diagnosis method based on I-V curve |
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| US20160087132A1 (en) * | 2014-09-19 | 2016-03-24 | Hamad Musabeh Ahmed Saif Alteneiji | Dynamic PV Module And Method Of Manufacturing |
| CN107463742A (en) * | 2017-08-01 | 2017-12-12 | 河海大学常州校区 | A kind of modeling method for photovoltaic module exception degradation failure |
| CN112803891A (en) * | 2021-01-19 | 2021-05-14 | 阳光电源股份有限公司 | Photovoltaic system fault diagnosis method and device |
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