Stopping PID at 1500 volts

• Researchers in Germany have actually created a "sturdy" examination to offer understanding right into the long-term results of capacity generated destruction in PV modulescomponents. The examinations work out past those developed by IEC criteria and also look for to direct makers and also financiers on the very best selection of products-- encapsulants specifically-- when it pertains to long-term PID resistance.

Researchers at Germany's Center for Solar Energy and also Hydrogen Research Baden-Württemburg (ZSW) today presented brand-new screening procedures made to offer PV capitalists as well as project programmers assurance concerning photovoltaic panel resistance to capacity generated destruction (PID).

The examinations were created to work out past those specified by the International Electrotechnical Commission in its common IEC TS 62804-1 routine, which usually calls for components to go through moist warm screening at 85 levels Celsius and also 85% moisture for 96 hrs at the module's ranked voltage-- 1,500 V most of the times-- as well as to preserve a minimum of 95% of first efficiency after the test.

PID is triggered by leak currents in between a panel's semiconductor product as well as various other system aspects and also can decrease a module's open-circuit voltage and also optimum power factor gradually, in many cases considerably.

' PID-free'.

Anti-PID steps exist and also suppliers have actually been offering 'PID cost-free' components for several years yet the flaw still stands for a substantial hazard to long-lasting efficiency and also a fear for insurance firms as well as capitalists. While aspects outside the module can add to PID, one of the most efficient method to preventing it seems design for far better resistance in tools.

The ZSW, collaborating with various other European institutes and also module makers under the EU-funded Solar EraNet project, looked for to exceed the IEC requirement and also subject components to "the deterioration of years in operation" to much better comprehend PID sensitivity. For the scientists, that indicated boosting the voltage to 2,500 V and also running the examination for 1,000 hrs with a conductive steel aluminum foil supplying call to the components. The examination likewise thinks a 'worst instance' situation and also did not think about healing results-- recognized to take place in the hrs of darkness.

Evidence of principle.

To verify its brand-new 'sturdy' method, the ZSW evaluated 2 kinds of solar battery-- one recognized to have solid PID resistance as well as an additional which was a lot more prone to the problem-- as well as integrated them, independently, with 3 various encapsulant products: typical EVA (ethylene plastic acetate); an EVA developed for added PID resistance; as well as a polyolefin compound. All the encapsulants had actually passed the basic IEC examination at 1,500 volts.

Components with typical EVA shed around 5% of efficiency after ZSW screening equal to 2 years in the field. Those with the specifically crafted EVA encapsulant withstood the matching of 22 years prior to losses passed 5%, and also the polyolefin enveloped components, according to the ZSW, revealed almost no indicators of PID also after the matching of 60 years in operation.