Canadian Solar Inc. has become one of the first providers to have passed two high voltage endurance tests. The Photovoltaic Institute (PI) Berlin tested the CS6-poly-series and the PV Evolution Labs assessed the CS5-mono-series and the CS6-poly-series. The tests measured the sensitivity of the module output parameters when exposed to high system voltages - formally known as Potential Induced Degradation (PID).
In compliance with the standard set by the PI Berlin, TUV Rhineland and the VDE (Association for Electrical, Electronic & Information Technologies), Canadian Solar modules were exposed to a negative socket voltage of 1,000 volt. During the test the grounded module front is covered in either aluminum foil or a layer of water. The-before-and-after performance rate was measured with a flasher under standard test conditions (STC). The Canadian Solar module performance rate was found to be still higher than 98 percent following the endurance test. Canadian Solar requested PI Berlin to double the standard stress time for the ultimate quality assurance.
All Canadian Solar modules demonstrated very little further degradation during the additional aging period and the final results were still qualified for the top rating, PID Class A, at PI Berlin.
"Such tests provide an important measure of orientation to our customers. The results demonstrate that they can count on the high quality of our products," said Dr. Shawn Qu, Chairman and CEO of Canadian Solar. "We believe that we have some of the most advanced and highest quality products available in the market today. One of the reasons for this is that we have never shied away from investing into this area. This has now paid off."
The Potential Induced Degradation phenomena in conventional crystalline cell technologies has recently gained industry attention.
While there is still no industry-wide acknowledged test standards available, Canadian Solar developed a test method together with the PV Evolution for this purpose, actively promoting the development of PID standards at the International Electrotechnical Commission (IEC). The PID test method applied by PI Berlin was developed by the TUV Rhineland, the PI Berlin, the VDE, and the Fraunhofer Institute for Solar Energy Systems ISE in conjunction with leading solar companies.