VDE-QT-PV001:2012/01

Transcription

1 1 VDE-QT-PV001:2012/01 VDE-QT-PV001:2012/01 Combined IEC ed.2, IEC ed. 1, IEC ed.2 plus VDE addendums

2 2 VDE-QT-PV001:2012/01 CONTENTS 1 Scope and object 5 2 Normative references 5 3 Sampling 7 4 Marking 7 5 Testing 7 6 Pass criteria 7 7 Major Visual defects 7 8 Report 7 9 Modifications 8 10 Test procedure Visual Inspection Maximum power determination Insulation test Measurement of temperature coefficients Measurement of nominal operating cell temperature (NOCT) Performance at STC and NOCT Performance at low irradiance Outdoor exposure test Hot-spot endurance test UV preconditioning test Thermal cycling test Humidity-freeze test Damp-heat test Robustness of terminations test Wet leakage current test Mechanical load test Hail Test Bypass diode thermal test EL-measurement Dynamic mechanical load test Requirements for construction Requirements for safety testing Application classes Test categories Application classes and their necessary test procedures Sampling Test Report 18

3 3 VDE-QT-PV001:2012/ Testing Pass criteria Test procedures Visual Inspection MST Accessibility test MST Cut susceptibility test MST Ground continuity test MST Impulse voltage test MST Partial discharge test MST Dielectric withstand test MST Wet leakage current test MST Temperature test MST Hot-spot test MST Fire test MST Bypass diode thermal test MST Reverse current overload test MST Module breakage test MST Conduit bending test MST Mechanical load test MST Robustness of terminations MST Terminal box knock out test Thermal cycling test 200 cycles MST 51a Thermal cycling test 50 cycles MST 51b Humidity freeze test MST Damp heat test MST UV-resistance test MST In line testing Tests Documentation Off Line Testing (Quarterly testing) Sampling Tests for all modules Visual Inspection Maximum power determination EL-check Tests for 4 Modules Preconditioning Insulation test Wet leakage test 21

4 4 VDE-QT-PV001:2012/ Dynamic load test Thermal cycling test Hot-spot test Damp heat test Wiring compartment test Reverse current overload test Ground continuity test Test sequence Corrective actions Routine testing 100% Routine testing 1% / daily tests Quarterly testing 24

5 5 VDE-QT-PV001:2012/01 VDE-QT-PV-001 (Combined IEC ed.2, IEC ed. 1, IEC ed.2 plus VDE addendums) Crystalline silicon terrestrial Photovoltaic (PV) Modules DESIGN QUALIFICATION, TYPE APPROVAL AND PHOTOVOLTAIC (PV) MODULE SAFETY QUALIFICATION 1 Scope and object This test base lays down requirements for the design qualification and type approval of crystalline silicon terrestrial photovoltaic modules. It is based on IEC 61215, IEC , IEC and UL It is written because initial module design certification and snapshot-wise control of manufacturing processes are both critical in ensuring high quality and reliable products in mass production. The 3 core issues are: 1. Stricter module design and safety qualification requirements 2. Continuous inline quality monitoring during mass production 3. Continuous offline process and quality monitoring of production sites The core issues lead to: Higher confidence in product quality due to continuous product monitoring on a stable statistical data base (larger sample size, higher sample frequency, combination of inline and offline tests) Proven long-term reliability due to continuous product and production site monitoring Better return on investment due to proven high reliability and low power degradation, i.e. minimized investment risk Increased bankability 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61215: Crystalline silicon terrestrial photovoltaic (PV) modules Design qualification and type approval. IEC : Photovoltaic (PV) module safety qualification Part 1: Requirements for

6 6 VDE-QT-PV001:2012/01 construction IEC : Photovoltaic (PV) module safety qualification Part 2: Requirements for testing UL 1703 Flat-Plate Photovoltaic Modules and Panels VDE PM 434: Test instruction for Factory Surveillance of terrestrial photovoltaic (PV) modules in accordance with VDE , -30-2, -31, -32.

7 7 VDE-QT-PV001:2012/01 3 Sampling This clause of IEC is applicable except the following modification: Number of samples: 14 modules. 4 Marking 5 Testing 6 Pass criteria This clause of IEC is applicable except the following modification: Pass / fail criteria is 5% max degradation between the single sequences and overall. 7 Major visual defects 8 Report

8 8 VDE-QT-PV001:2012/01 Table 1 Summary of test levels Test Title Test conditions 10.1 Visual inspection See IEC Maximum power determination See IEC Insulation test See IEC Measurement of temperature coefficients See IEC Measurement of NOCT See IEC Performance at STC and NOCT See IEC Performance at low irradiance (see note 1) See IEC Outdoor exposure test See IEC Hot-spot endurance test See IEC UV Preconditioning See IEC Thermal cycling test 50 and 2 times 200 cycles from 40 C to + 85 C with STC peak power current during 2 times 200 cycles Humidity-freeze test 10 cycles from +85 C, 85 % RH to 40 C Damp-heat test 1000 h and 500 h at +85 C, 85 % RH Robustness of termination test See IEC and UL 1703 Clause 42 Wiring compartment Securement test Wet leakage current test See IEC Mechanical load test See IEC Hail test See IEC Bypass diode thermal test See IEC EL-measurement See Mechanical cycling test 1000 cycles with 1000 Pa for front and rear side 9 Modifications The IEC and IEC retesting guideline is applicable except the following modification: The relevant test sequences of VDE-PV-QT-001 apply.

9 9 VDE-QT-PV001:2012/01 10 Test procedure

10 10 VDE-QT-PV001:2012/ Visual inspection 10.2 Maximum power determination 10.3 Insulation test 10.4 Measurement of temperature coefficients 10.5 Measurement of nominal operating cell temperature (NOCT) 10.6 Performance at STC and NOCT 10.7 Performance at low irradiance 10.8 Outdoor exposure test 10.9 Hot-spot endurance test UV preconditioning test Thermal cycling test This clause of IEC is applicable except the following addition: Final measurements After a minimum recovery time of 1 h, repeat the tests of 10.1, 10.2 and For TC 200, repeat the whole sequence Humidity-freeze test

11 11 VDE-QT-PV001:2012/ Damp-heat test This clause of IEC is applicable except the following modification: Final measurements After a recovery time of between 2 h and 4 h, repeat the tests of 10.3 and Repeat the tests of 10.1 and Repeat the whole sequence for additional 500 h Robustness of terminations test This clause of IEC is applicable with the following addition: Wiring compartment Securement test The tensile force required to separate a wiring compartment or box from a module shall not be less than 156 N ± 1 N (16kg) or 4 times the weight of the wiring compartment or the box, whichever is greater. For a test in which the superstrate or substrate fails prior to the adhesive, the force required to cause the superstrate or substrate to fail shall be used to determine compliance, and shall not be less than the specified minimum separation force The force is to be applied so as to separate the wiring compartment or box from the module. The force is to be applied for 2 minutes Final measurements Repeat the tests of 10.1, 10.2, 10.3 and Wet leakage current test Mechanical load test Hail test Bypass diode thermal test EL measurement Purpose Purpose of this test is to identify cracks in cells which are caused in the module manufacturing process that might influence the long term reliability of the module.

12 12 VDE-QT-PV001:2012/ EL-Setup CCD-camera or even better an IR-camera that is sensitive in the range of 1200 to 1000nm (c- Si). Resolution: 1 pixel in the image should represent not more then 1 mm² on the PV module (e.g. 1.6Mpix for a 1.6m² module): Wafer brick patterns, grain boundaries, grid-fingers, finger interruptions, contact pads from backside/front side, cracks etc. must be clearly visible. Image processing (stitching, cropping, contrast) can be done, but effects like antialiasing should be avoided UV-VIS filters to block unwanted light coming from the surrounding walls can be used A DC power supply shall be connected to the module with positive output connected to the positive terminal of the module. A current of I sc +/-10% must be driven through the module Integration time must be adjusted to reach best possible signal-to-noise ratio (typically between 5 and 100secs) EL failure catalogue Cell cracks a): Cracks w/o dark areas and possible finger interrupts. Not allowed: greater than 2 cracks in any one cell greater than 3 cracked cells within a 60 cell module dark lines/curves over one or several cells with "tree-pattern like cracks

13 13 VDE-QT-PV001:2012/01 Accept if Examples Cell type Mono c-si Cells Pass Fail Cell type Multi c-si Cells Pass Fail

14 14 VDE-QT-PV001:2012/01 b) Isolated cell area A part of the cell is isolated from the active area due to cracking. An isolated area is defined as one in which there is no redundant current path connecting it to the active area of the cell. Not allowed: Examples greater than 10% area isolated within any one cell greater than 3 cells with less than 10% area isolated within a 60 cell module Cell type Mono c-si Cells Pass Fail Cell type Multi c-si Cells Pass Fail

15 15 VDE-QT-PV001:2012/ Dark cells Cells uniformly dark due to a short through cell, damaged diode, or mismatched cell bins. Not allowed: Any cell that is completely dark (with or without halo) Any group/string of cells that is completely dark Generally not allowed, because of Hot-Spot risk Examples Cell type Mono c-si Cells Fail Cell type Multi c-si Cells Fail

16 16 VDE-QT-PV001:2012/ Native cell issues Native cell issues include: wafer repetitive patterns, ingot edge marks, scratches or other artificial structures. Modules are not rejected for any of these defects because they have no long term impact on module reliability or performance. Allowed: Scratches or artificial structures Finger interrupts caused by screen-printing issues (mostly repeatedly visible in one module) Examples Cell type Mono c-si Cells Pass Cell type Multi c-si Cells Pass

17 17 VDE-QT-PV001:2012/ Dynamic mechanical load test Purpose The purpose of this test is to ensure that the test module can withstand wind gust loading. It also enables the evaluation of power loss associated with broken cells Apparatus A rigid test base which enables the modules to be mounted according to the manufacturers specifications. The test base shall enable the module to deflect freely during the load application. Suitable equipment or pressure means that enable the load to be applied in a gradual, uniform manner Procedure Mount the module on the test base using the method prescribed by the manufacturer. If there are different possibilities, use the worst case, where the distance between the fixing points is at maximum. Across the surface of the module, uniformly cycle a load of at minimum ±1000 Pa, for 1000 times (1 cycle consists of a positive load of 1000 Pa and a negative load of 1000 Pa.) The rate of cycling shall be no less than 0.1 Hz and no more 1Hz Final measurements Repeat the tests of 10.1, 10.2, 10.3 and Requirements The requirements are as follows: No evidence of major visual defects, as defined in Clause 7; The degradation of maximum output power shall not exceed 5% of the value measured before the test; Insulation resistance meets the same requirements as for the initial measurement 11 Requirements for construction IEC applies without modification.

18 18 VDE-QT-PV001:2012/01 12 Requirements for safety testing 12.1 Application classes Clause 3 of IEC is applicable Test categories Clause 4 of IEC is applicable Application classes and their necessary test procedures Clause 5 of IEC is applicable Sampling Clause 6 of IEC is applicable Test Report Clause 7 of IEC is applicable Testing Clause 8 of IEC is applicable Pass criteria Clause 9 of IEC is applicable Test procedures Clause 10 of IEC is applicable Visual Inspection MST 01 Clause 10.1 of IEC is applicable Accessibility test MST 11 Clause 10.2 of IEC is applicable Cut susceptibility test MST 12 Clause 10.3 of IEC is applicable Ground continuity test MST 13 Clause 10.4 of IEC is applicable.

19 19 VDE-QT-PV001:2012/ Impulse voltage test MST 14 Clause 10.5 of IEC is applicable Partial discharge test MST 15 Clause 11.1 of IEC is applicable Dielectric withstand test MST 16 Clause 10.6 of IEC is applicable Wet leakage current test MST 17 Clause of IEC is applicable Temperature test MST 21 Clause 10.7 of IEC is applicable Hot-spot test MST 22 Clause 9 of IEC is applicable Fire test MST 23 Clause 10.8 of IEC is applicable Bypass diode thermal test MST 25 Clause of IEC is applicable Reverse current overload test MST 26 Clause 10.9 of IEC is applicable Module breakage test MST 32 Clause of IEC is applicable Conduit bending test MST 33 Clause 11.2 of IEC is applicable Mechanical load test MST 34 Clause of IEC is applicable Robustness of terminations MST 42

20 20 VDE-QT-PV001:2012/01 MST 42: must be performed in addition Terminal box knock out test Clause 11.3 of IEC is applicable Thermal cycling test 200 cycles MST 51a Clause of IEC is applicable together with the additions of clause of VDE- QT-PV Thermal cycling test 50 cycles MST 51b Clause of IEC is applicable Humidity freeze test MST 52 Clause of IEC is applicable Damp heat test MST 53 Clause of IEC is applicable together with the additions of clause of VDE QT-PV UV-resistance test MST 54 Clause of IEC is applicable. 13 In line testing 13.1 Tests The tests listed in PM 434 are applicable with the following additional tests: Additional Tests: Routine test 100%: EL testing in accordance with Routine test 1% of the modules produced per day: Wet-Leakage test in accordance with Routine test 1 sample per site per day: Grounding test in accordance with IEC , MST 13 except that I test >= Ir Reverse current overload test in accordance with IEC , MST 26 except that I test >= Ir

21 21 VDE-QT-PV001:2012/ Documentation The test results must be documented in MS-Excel and must be forwarded for inspection to VDE together with the samples for Quarterly Tested (clause 14). 14 Off Line Testing (Quarterly testing) 14.1 Sampling: Randomly sampled modules to get each laminator/stringer checked within a year (dependent on lines/sub lines). Min. 20 Modules or one standard shipping box/palette per quarter including the complete documentation about the Routine Testing (clause 13) in MS-Excel for the modules produced in the last quarter Tests for all modules: Visual inspection In accordance with clause 10.1 including check of the electrical sorting criteria (ESCs) Maximum power determination In accordance with Additionally compare the power measured at the initial power measurement with the power given on the label. The results must be within the tolerance specified by the manufacturer. Compare with original factory measurement and compare with label. (Should be shipped) EL-check In accordance with clause EL inspection for transportation failures and EL-sorting verification Tests for 4 Modules (plus control sample) Preconditioning Modules shall be exposed to sunlight (real or simulated) of an irradiation level of 5 kwh/m² to 5,5 kwh/m² Insulation test In accordance with clause Wet leakage test In accordance with clause Dynamic load test In accordance with clause 10.20

22 22 VDE-QT-PV001:2012/ Thermal cycling test In accordance with clause with the following modification: Number of Cycles Hot-spot test In accordance with clause Damp heat test In accordance with clause except the following modification: Testing time is 250 h Wiring compartment Securement test In accordance with clause Reverse current overload test In accordance with MST 26 of IEC Ground continuity test In accordance with IEC , MST 13

23 23 VDE-QT-PV001:2012/ Test Sequence

24 24 VDE-QT-PV001:2012/01 15 Corrective actions In this clause the corrective actions are described which must be taken in case of failures within the 100% routine testing, the routine testing 1% or the daily tests. Every failure must be reported to VDE immediately Routine testing 100% If only one module fail test check for the reason (e.g. defective j-box cable) and assume single event keep production running, check e.g. incoming goods inspection create report. If more modules are failing the tests assume process related or material related issue. Stop production and figure out / solve the problem. Create report Routine testing 1% / daily tests Check one module produced before and after failed module. If one of the 2 modules failed assume process related issue stop production and investigate the problem. Create report. If both modules pass, assume failure was a single event keep production running and create report for VDE Quarterly testing If one module fails, investigate the issue and create report. If only one module is tested in the sequence, test a second one. If the second one passes the relevant tests, take it as a single event. If more than one module fails the quarterly testing, a systematic problem must be assumed. The Quality-Tested mark is not valid anymore. Remove the label from last quarter s production and check if modules still fulfill IEC criteria, if not, recall modules.