1、Designation: E1362 10Standard Test Method forCalibration of Non-Concentrator Photovoltaic SecondaryReference Cells1This standard is issued under the fixed designation E1362; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers calibration and characterizationof secondary terrestrial photovoltaic reference cells to a
3、desiredreference spectral irradiance distribution. The recommendedphysical requirements for these reference cells are described inSpecification E1040. Reference cells are principally used in thedetermination of the electrical performance of a photovoltaicdevice.1.2 Secondary reference cells are cali
4、brated indoors usingsimulated sunlight or outdoors in natural sunlight by referenceto a primary reference cell previously calibrated to the samedesired reference spectral irradiance distribution.1.3 Secondary reference cells calibrated according to thistest method will have the same radiometric trac
5、eability as theof the primary reference cell used for the calibration. There-fore, if the primary reference cell is traceable to the WorldRadiometric Reference (WRR, see Test Method E816), theresulting secondary reference cell will also be traceable to theWRR.1.4 This test method applies only to the
6、 calibration of aphotovoltaic cell that demonstrates a linear short-circuit currentversus irradiance characteristic over its intended range of use,as defined in Test Method E1143.1.5 This test method applies only to the calibration of aphotovoltaic cell that has been fabricated using a singlephotovo
7、ltaic junction.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to
8、 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E490 Standard Solar Constant and Zero Air Mass SolarSpectral Irradiance TablesE691 Practice for Conducting an Interlaboratory Study t
9、oDetermine the Precision of a Test MethodE772 Terminology Relating to Solar Energy ConversionE816 Test Method for Calibration of Pyrheliometers byComparison to Reference PyrheliometersE927 Specification for Solar Simulation for PhotovoltaicTestingE948 Test Method for Electrical Performance of Photov
10、ol-taic Cells Using Reference Cells Under Simulated SunlightE973 Test Method for Determination of the Spectral Mis-match Parameter Between a Photovoltaic Device and aPhotovoltaic Reference CellE1021 Test Method for Spectral Responsivity Measure-ments of Photovoltaic DevicesE1039 Test Method for Cali
11、bration of Silicon Non-Concentrator Photovoltaic Primary Reference Cells UnderGlobal Irradiation3E1040 Specification for Physical Characteristics of Non-concentrator Terrestrial Photovoltaic Reference CellsE1125 Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Referen
12、ce Cells Us-ing a Tabular SpectrumE1143 Test Method for Determining the Linearity of aPhotovoltaic Device Parameter with Respect To a TestParameterE1328 Terminology Relating to Photovoltaic Solar EnergyConversionG173 Tables for Reference Solar Spectral Irradiances: Di-rect Normal and Hemispherical o
13、n 37 Tilted Surface1This test method is under the jurisdiction of ASTM Committee E44 on Solar,Geothermal and OtherAlternative Energy Sources and is the direct responsibility ofSubcommittee E44.09 on Photovoltaic Electric Power Conversion.Current edition approved June 1, 2010. Published July 2010. Or
14、iginally approvedin 1995. Last previous edition approved in 2005 as E1362-05. DOI: 10.1520/E1362-10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Do
15、cument Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 DefinitionsDefinitions of terms u
16、sed in this testmethod may be found in Terminology E772 and in Terminol-ogy E1328.3.2 Definitions of Terms Specific to This Standard:3.2.1 junction temperature, nsynonym for cell tempera-ture. E13283.2.2 test light source, na source of radiant energy usedfor the secondary reference cell calibration,
17、 either naturalsunlight or a solar simulator.3.3 Symbols:3.3.1 The following symbols and units are used in this testmethod:Ccalibration constant, Am2W1,Eirradiance, Wm2,Ettotal irradiance, Wm2,Icurrent, A,Ipprimary reference cell short-circuit current, A,Issecondary reference cell short-circuit curr
18、ent, A,Iscshort-circuit current, A,Lcollimator length, m,Mspectral mismatch parameter,ntotal number of data points,rcollimator receiving aperture radius, m,Rcollimator opening aperture radius, m,Raabsolute spectral response, AW1,Rrrelative spectral response,Sstandard deviation,Ttemperature, C,atempe
19、rature coefficient of reference cell, C1,uocollimator opening angle, , andlwavelength, nm or m.3.3.2 Symbolic quantities that are functions of wavelengthappear as X(l).4. Summary of Test Method4.1 The calibration of a secondary photovoltaic referencecell consists of measuring the short-circuit curre
20、nt of the cellunder natural or simulated sunlight using a primary referencecell to measure the incident irradiance. In addition to theshort-circuit current, the relative spectral response of the cell tobe calibrated and the relative spectral irradiance of the lightsource must be determined. Errors i
21、n the short-circuit currentdue to the spectral irradiance of the light source and thespectral response of the primary reference cell are thencorrected by dividing the short-circuit current by the spectralmismatch parameter. Also, if the temperature of the cell is not25 6 1C, the temperature coeffici
22、ent for the short-circuitcurrent is needed. The list of necessary test methods is asfollows:4.1.1 The spectral response of the cell to be calibrated isdetermined in accordance with Test Methods E1021.4.1.2 The cells short-circuit current temperature coefficientis determined experimentally by measuri
23、ng short-circuit cur-rent at various temperatures and computing the temperaturecoefficient.4.1.3 Linearity of short-circuit current versus irradiance isdetermined in accordance with Test Method E1143.4.1.4 The relative spectral distribution of the light source isdetermined using a spectral irradianc
24、e measurement instrumentas specified in Test Method E973.5. Significance and Use5.1 The electrical output of photovoltaic devices is depen-dent on the spectral content of the source illumination and itsintensity. To make accurate measurements of the performanceof photovoltaic devices under a variety
25、 of light sources, it isnecessary to account for the error in the short-circuit currentthat occurs if the relative spectral response of the primaryreference cell is not identical to the spectral response of the cellto be calibrated.Asimilar error occurs if the spectral irradiancedistribution of the
26、test light source is not identical to the desiredreference spectral irradiance distribution. These errors areaccounted for by the spectral mismatch parameter M (TestMethod E973), a quantitative measure of the error in theshort-circuit current measurement. It is the intent of this testmethod to provi
27、de a recognized procedure for calibrating,characterizing, and reporting the calibration data for secondaryphotovoltaic reference cells.5.2 A secondary reference cell is calibrated to the samereference spectral irradiance distribution as the primary refer-ence cell used during the calibration. Primar
28、y reference cellscan be calibrated by use of Test Method E1125 or Test MethodE1039.NOTE 1No standards for calibration of reference cells to the extra-terrestrial spectral irradiance distribution presently exist.5.3 Asecondary reference cell should be recalibrated yearly,or every six months if the ce
29、ll is in continuous use outdoors.5.4 Recommended physical characteristics of referencecells are provided in Specification E1040.5.5 Because silicon solar cells made on p-type substrates aresusceptible to a loss of Iscupon initial exposure to light, it isrequired that newly manufactured reference cel
30、ls be lightsoaked at an irradiance level greater than 850 W/m2for2hprior to initial charcterization in Section 7.6. Apparatus6.1 Normal Incidence Tracking Platform (for calibrationsconducted in natural sunlight)A tracking platform used tofollow the sun that holds both the primary reference cell andt
31、he cell to be calibrated. The tracker shall be able to track thesun to within 60.5 during the calibration procedure.6.1.1 When the calibration is performed in direct naturalsunlight, each cell and the spectral irradiance measurement(see 6.7) shall have collimators that meet the requirements ofAnnex
32、A1 of Test Method E1125.6.1.2 When the calibration is performed in global normalconditions, no significant energy reflected from surroundingbuildings or any other surfaces in the vicinity of the test standshall be allowed onto the reference cells for the duration of thecalibration period. Care shall
33、 be taken to conduct the calibra-tion in a location or manner such that a condition of highground reflectance is avoided. If significant reflection canoccur, provision shall be made on the tracker to shield thereference cells by the use of a horizon shield. This horizonshield shall consist of a blac
34、k nonreflecting surface, and shall,E1362 102as viewed by each reference cell, block the view downwardfrom the local horizon to the lowest extremes of the field ofview.6.2 Solar Simulator A light source that meets the require-ments of a Class A solar simulator in terms of the nonunifor-mity and tempo
35、ral instability of the total irradiance, and meetsthe requirements of a Class B solar simulator in terms of thespectral distribution of irradiance performance, as specified inSpecification E927.6.3 Temperature Measurement EquipmentAn instrumentor instruments used to measure the cell temperature of b
36、oth theprimary reference cell and the cell to be calibrated that has aresolution of at least 0.1C, and a total error of less than 61Cof reading.6.3.1 Sensors used for the temperature measurements mustbe located in a position that minimizes any temperaturegradients between the sensor and the photovol
37、taic devicejunction.6.4 Current Measurement EquipmentInstruments used tomeasure the Iscof the reference cell to be calibrated and theprimary reference cell that has a resolution of at least 0.02 % ofthe maximum current encountered, and a total error of less than0.1 % of the maximum current encounter
38、ed.6.5 Temperature Control Block (optional)A device tomaintain the temperature of the reference cells at 25 6 1C forthe duration of the calibration.6.6 Spectral Response Measurement Equipment, as requiredby Test Methods E1021.6.6.1 The wavelength interval between spectral responsedata points shall b
39、e a maximum of 50 nm.6.7 Spectral Irradiance Measurement Equipment,asre-quired by Test Method E973.7. Characterization7.1 Cells being calibrated shall be characterized by thefollowing methods:7.1.1 Spectral ResponseDetermine the relative spectralresponse (optionally the absolute spectral response) o
40、f the cellto be calibrated in accordance with Test Methods E1021.7.1.2 Temperature CoeffcientDetermine the temperaturecoefficient, a, of the cell to be calibrated as follows:7.1.2.1 Using the electrical measurement equipment, mea-sure Iscat four or more temperatures over at least a 50Ctemperature ra
41、nge centered around 35C. The irradiance shallbe at least 750 Wm2and less than 1100 Wm2, as measuredwith a second reference cell.7.1.2.2 Divide each value of Iscby the normalized instanta-neous irradiance level at the time of each measurement, andplot the resulting data versus measurement temperature
42、.NOTE 2The normalized instantaneous irradiance can be determinedby dividing a reference cells Iscby its calibration constant.7.1.2.3 Determine the temperature coefficient by performinga least-squares fit of the data to a straight line. The slope of theline divided by the interpolated Iscvalue at 25C
43、 is thetemperature coefficient.7.1.3 LinearityDetermine the short-circuit current versusirradiance linearity of the cell being calibrated in accordancewith Test Method E1143 for the irradiance range 750 to 1100Wm2.7.1.3.1 For reference cells that use single-crystal siliconsolar cells, or for referen
44、ce cells that have been previouslycharacterized, the short-circuit current versus irradiance linear-ity determination is optional.7.1.4 Fill Factor Determine the fill factor of the cell to becalibrated from the IV curve of the device, which shall bemeasured in accordance with Test Method E948.8. Pro
45、cedure8.1 Mount the primary reference cell and the cell to becalibrated coplanar in close proximity. For natural sunlightmeasurements, orient the cells to within 60.5 of normal to thesuns direct beam.8.2 Verify that the following test condition requirements aremet:8.2.1 Total Irradiance The total ir
46、radiance shall be 750Wm2and 1100 Wm2at the time of the calibration, asmeasured by the primary reference cell.8.2.2 Irradiance StabilityThe irradiance shall be suffi-ciently stable so that variation in the primary reference cellshort-circuit current is less than 61 % during the calibration.8.2.3 Clou
47、ds and Haze For natural sunlight measure-ments, the sky must be clear with no observable cloudformations within a 30 half-angle cone surrounding the sun.8.3 Measure the Iscof both the primary reference cell andthe cell being calibrated during the same time period. Duringthis time period, measure the
48、 incident spectral irradiance inaccordance with Test Method E973.NOTE 3For calibrations using solar simulation, it is not necessary tomeasure the spectral irradiance at the same time as the short-circuit currentif it has been determined that the average relative spectral irradiance willnot change mo
49、re than 63 % over any 100-nm wavelength intervalbetween the two measurements.8.4 Measure the temperature of both cells.8.5 Perform 8.2, 8.3, and 8.4 at least three times. One datapoint will be obtained for each time 8.2, 8.3, and 8.4 areperformed.9. Calculation of Results9.1 Spectral MismatchDetermine the spectral mismatchparameter M for each data set in accordance with Test MethodE973.9.1.1 Reject any data points where the spectral mismatchparameter is not 1.00 6 0.20.9.2 Reference Cell Calibration ConstantFor each
