1、Designation: E 2527 09Standard Test Method forElectrical Performance of Concentrator TerrestrialPhotovoltaic Modules and Systems Under Natural Sunlight1This standard is issued under the fixed designation E 2527; the number immediately following the designation indicates the year oforiginal adoption
2、or, in the case of revision, the year 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 the determination of the elec-trical performance of p
3、hotovoltaic concentrator modules andsystems under natural sunlight using a normal incidencepyrheliometer.1.2 The test method is limited to module assemblies andsystems where the geometric concentration ratio specified bythe manufacturer is greater than 5.1.3 This test method applies to concentrators
4、 that usepassive cooling where the cell temperature is related to the airtemperature.1.4 Measurements under a variety of conditions are al-lowed; results are reported under a select set of concentratorreporting conditions to facilitate comparison of results.1.5 This test method applies only to conce
5、ntrator terrestrialmodules and systems.1.6 This test method assumes that the module or systemelectrical performance characteristics do not change during theperiod of test.1.7 The performance rating determined by this test methodapplies only at the period of the test, and implies no past orfuture per
6、formance level.1.8 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.
7、2. Referenced Documents2.1 ASTM Standards:2D 6176 Practice for Measuring Surface Atmospheric Tem-perature with Electrical Resistance Temperature SensorsE 772 Terminology Relating to Solar Energy ConversionE 816 Test Method for Calibration of Pyrheliometers byComparison to Reference PyrheliometersE 1
8、036 Test Methods for Electrical Performance of Non-concentrator Terrestrial Photovoltaic Modules and ArraysUsing Reference CellsE 1328 Terminology Relating to Photovoltaic Solar EnergyConversion2.2 IEEE Standard:IEEE 929-2000 Recommended Practice for Utility Interfaceof Photovoltaic (PV) Power Syste
9、ms3. Terminology3.1 DefinitionsDefinitions of terms used in this testmethod may be found in Terminology E 772, TerminologyE 1328, and IEEE Standard 929.3.2 Definitions of Terms Specific to This Standard:3.2.1 Concentrator Reporting Conditions, nthe ambienttemperature, wind speed, and direct normal s
10、olar irradiance towhich concentrator module or system performance data arecorrected3.2.2 system, na photovoltaic module or array connectedto an inverter.3.3 Symbols: The following symbols and units are used inthis test method:E = direct normal irradiance, Wm-2Eo= reporting direct normal irradiance o
11、f 850 Wm-2P = maximum power, WPo= maximum power at concentrator reporting conditions(Eo, To, and Vo), WTa= ambient temperature, CTo= reporting ambient temperature of 20Cv = wind speed, ms-1vo= reporting wind speed of 4 ms-11This test method is under the jurisdiction of ASTM Committee E44 on Solar,Ge
12、othermal and Other Alternative Energy Sources and is the direct responsibility ofSubcommittee E44.09 on Photovoltaic Electric Power Conversion.Current edition approved Jan. 15, 2009. Published February 2009. Originallyapproved in 2006. Last previous edition approved in 2006 as E 2527-06.2For referen
13、ced 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 Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West C
14、onshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 Determining the performance of a photovoltaic moduleor system under natural sunlight consists of measuring themaximum power over a range of irradiance and air tempera-ture.4.2 Amultiple linear regression is used to rate the maxim
15、umpower3at standard concentrator reporting conditions, definedas To= 20C, vo=4ms-1, Eo= 850 Wm-2.4.2.1 A direct normal irradiance of 850 Wm-2was selectedfrom a resource assessment study4that showed when the globalnormal solar irradiance is near the 1000 Wm-2used in ratingflat-plate photovoltaic modu
16、les, the direct normal irradiance isabout 850 Wm-2.4.3 The actual test data and the performance results are thenreported.5. Significance and Use5.1 It is the intent of this test method to provide a recog-nized procedure for testing and reporting the electrical perfor-mance of a photovoltaic concentr
17、ator module or system.5.2 If an inverter is used as part of the system, this testmethod can provide a dc or ac rating or both. The dc or acrating depends on whether the inverter input or output ismonitored.5.3 The test results may be used for comparison among agroup of modules or systems from a sing
18、le source. They alsomay be used to compare diverse designs, such as products fromdifferent manufacturers. Repeated measurements of the samemodule or system may be used for the study of changes indevice performance over a long period of time or as a result ofstress testing.5.4 The test method is limi
19、ted to modules and systemswhere the concentrated irradiance on the component cells isgreater than 5000 Wm-2at Eo. This limitation is necessarybecause the total irradiance is measured with a radiometer witha field of view less than 6 and because the correlation betweenthe direct irradiance and the po
20、wer produced decreases withincreasing concentrator field of view.5.5 This test method assumes that the regression equationaccurately predicts the concentrator performance as a functionof total irradiance with a fixed spectral irradiance, wind speed,and air temperature. The spectral distribution will
21、 be seasonaland site specific because of optical air mass, water vapor,aerosols, and other meteorological variables.6. Apparatus6.1 Test FixtureA platform that maintains an incidenceangle to the sun of less than 0.5. If the manufacturersspecifications require more accurate tracking than 0.5 inci-den
22、ce angle, the manufacturers specifications should be fol-lowed. Concentrator systems shall be tested as installed.6.2 Air Temperature Measurement EquipmentThe instru-ment or instruments used to measure the temperature of the airshall have a resolution of at least 0.1C, and shall have a totalerror of
23、 less than 61C of reading. The instrument sensorshould be between 1 and 10 m upwind from the geometricalcenter of the receiver and be mounted at least 2 m above theground. Further details on air temperature measurements canbe found in Practice D 6176.6.3 Irradiance Measurement EquipmentA secondary r
24、ef-erence pyrheliometer calibrated according to Test MethodE 816.6.4 Wind Speed Measurement EquipmentThe instrumentused to measure the wind speed should have an uncertainty ofless than 0.5 ms-1. The instrument should be between 1 and 10m away from the nearest edge of the receiver and be mountedat le
25、ast 2 m above the ground. Ideally, the instrument should beat the center height of the receiver and located in the directionof the prevailing wind. Care should be taken that the instru-ment readings are not affected by the test fixture or nearbyobstacles.6.5 Power Measurement EquipmentExamples of ac
26、cept-able instrumentation to measure the output power of themodule or system under test include:6.5.1 Current-voltage measurement instrumentation re-quired by Test Methods E 1036,6.5.2 ac or dc current and voltage measurement instrumen-tation, and6.5.3 ac or dc power meter.7. Procedure7.1 If require
27、d, mount the module or system to be rated onthe tracking platform7.2 Connect the module or system to be rated to the powermeasurement equipment.7.3 Measure the direct solar irradiance E, air temperatureTa, and the wind speed v.7.4 Measure the maximum power according to 7.2.9 of TestMethods E 1036. I
28、f an inverter is part of the system, measurethe ac or dc output power of the system.7.5 Ensure the maximum interval between data points is 5min.7.6 Reject data when the direct normal solar irradiance isless than 750 W m-2, the irradiance varies by more than 10 %from the maximum value to the minimum
29、value recordedduring any 10 min interval, or the wind speed is greater than 8ms-1. If the wind speed exceeds 15 m s-1, reject all data duringthe succeeding 10 min interval.7.7 Repeat 7.3 through 7.6 until at least 20 valid points areobtained. For best results the data points should be distributedaro
30、und the standard concentrator reporting conditions (To, vo,and Eo).3Hester, S. I., Townsend, W. T., Clements, W. T., and Stolte, W. J., “PVUSALessons Learned from Startup and Early Operation,” Proc. of the 21st IEEEPhotovoltaics Spec. Conf., IEEE, New York, NY, 1990, pp. 937-943.4Kurtz, S., Myers, D
31、., Townsend, T., Whitaker, C., Maish, A., Hulstrom, R., andEmery, K., “Outdoor Rating Conditions for Photovoltaic Modules and Systems,”Solar Energy Mater. Solar Cells 62, 2000, pp. 379-391.E25270928. Calculation of Results8.1 Compute the regression coefficients a1, a2, a3, a4byperforming a multiple
32、linear regression of P as a function of E,v, and Tausing:5P 5 Ea11 a2 E 1 a3 Ta1 a4 v! (1)8.2 Calculate the maximum power at the concentrator re-porting conditions:Po5 Eoa11 a2 Eo1 a3 To1 a4 vo! (2)8.3 If the standard error of estimate for Pois greater than 3% repeat 7.3 through 7.5.9. Report9.1 The
33、 end user ultimately determines the amount ofinformation to be reported. Listed below are the minimum,mandatory reporting requirements:9.2 Concentrator Test Module or System Description:9.2.1 Identification,9.2.2 Physical description, and9.2.3 Aperture area.9.3 Radiometer Description:9.3.1 Identific
34、ation,9.3.2 Physical description,9.3.3 Calibration laboratory,9.3.4 Calibration procedure,9.3.5 Date of calibration, and9.3.6 Calibration constant.9.4 Description of power measurement equipment andmethod.9.5 Test Conditions:9.5.1 Geographical location, and9.5.2 Date and time of tests.9.6 Test Result
35、s:9.6.1 Table of P, E, v, Taused in the regression or graph ofthe data and fit,9.6.2 Number of days, and number of points used in theregression analysis, and9.6.3 Regression coefficients and standard error of estimate.9.6.4 If range of Todoes not encompass the reportedambient temperature, To, then t
36、he report should include a notethat the reporting data is extrapolated and the maximum andminimum of Toshould be reported.10. Precision and Bias10.1 PrecisionIt is not practicable to specify the precisionof the concentrator performance rating using results of aninterlaboratory study, because the res
37、ults are site and timespecific (see 5.5) and such a study would require circulating atleast six stable concentrator modules and associated trackinghardware between all participating laboratories. Factors thatcontribute to the total precision include:10.1.1 Temporal variations of the solar spectrum a
38、nd totalirradiance during the measurement of the total irradiance andmaximum power.10.1.2 Variation of the direct normal spectral irradiancefrom data point-to-data point will introduce an error becausethe data is not being referenced to a fixed reference spectralirradiance distribution.10.1.3 Temper
39、ature variations in the device under test notcorrelated with E, v, and Ta. This may arise from the finite massof the concentrator assembly or thermal gradients between thecell junction temperature and the rest of the concentrator.10.1.4 Electronic instrumentation used to measure the out-put power.10
40、.2 The contribution of bias to the total error will dependupon the bias of each individual parameter used for thedetermination of P, E, v, and Ta.10.2.1 The location of the temperature sensor used tomeasure Tawith respect to the concentrator will appear as abias error.10.2.2 An absolute accuracy of
41、0.45 % for terrestrial radio-metric measurements has been established for absolute cavityradiometers that have been compared with the World Radio-metric reference. If a secondary reference pyrheliometer isused, a 1% transfer error from the cavity radiometer should beexpected when utilizing procedure
42、s of Test Method E 816.10.2.3 Misalignment between the sun and concentratormodule will introduce a bias error that will depend on theconcentration ratio.11. Keywords11.1 concentrator; modules; performance; photovoltaic; rat-ing; reporting; systems; testingASTM International takes no position respect
43、ing the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This stan
44、dard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internatio
45、nal Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.
46、This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).5Burden, R. L., and Faires, J. D., Numerical Analysis, 3rd ed., Prindler, Weber& Schmidt, Boston, MA, 1985, p. 42 ff.E2527093
