Testing and verification are key parts of the development process – and good test results have a positive effect on the entire value chain

PolyTech has one of the biggest laboratories in the world for tests using artificial lightning
It makes perfect sense to conduct tests and verification at multiple levels throughout the process to develop a new Lightning Protection System (LPS). Early testing improves the likelihood of the finished system passing the final verification – verification which is so incredibly important in assuring the high level of operational reliability that is expected in the wind power industry, and which is also necessary when a new wind turbine is to be certified.

All our laboratory tests are performed pursuant to the latest standards, and the test methods we use at PolyTech are accredited in accordance with the IEC 17025 standard.

Capture efficiency test
One important aspect to test is the capacity of the Lightning Protection System to capture a lightning strike and ensure that the lightning only hits dedicated strike points on a wind turbine blade, for example – and not conductive structural components or cables inside the blade.

In our Lightning Lab, we test the capture efficiency using special systems for high-voltage tests where the voltage during the test exceeds 2 million volts. The test systems thus simulate natural physical conditions that define the strike process.

Consequential discharge test
A lightning impulse is seldom isolated; it is typically followed by a number of consequential discharges that often strike the same point as the first impulse. It is extremely important to simulate this phenomenon during tests. It can have literally fatal consequences if a wind turbine blade is unable to withstand the impacts from the consequential discharges of a lightning strike.

Physical damage test
Once the capture efficiency of a Lightning Protection System has been tested and found sufficient, the next step is to subject the system to the electromechanical forces that are part of a natural strike.

These tests are performed using high current – in excess of 200,000 A – with the associated high levels of energy and charge.

Wear and service life test
As a final, but remarkably important, part of the work to test a Lightning Protection System, we measure surface erosion on all lightning receptors, transfer systems, etc. with the objective of expressing the scope of wear and the expected service life as firm figures. This makes it possible to define the intervals for servicing the Lightning Protection System and replacing its wearing parts.

PolyTech has equipment that can run tests with exceptionally high levels of current and energy, even on extremely large test objects such as entire blades, hubs and nacelles.

What is more, the test equipment is mobile. So in addition to running tests in our own accredited laboratories, we can perform tests on wind turbine components at external locations where this makes more sense on account of logistical considerations, etc.

Why have your lightning tests performed at PolyTech?

• The biggest Lightning Lab in the world
• Accredited by DANAK in accordance with the ISO 17025 standard
• Tailor-made flexible lightning tests for the wind power industry
• All relevant electrical tests and high-voltage tests
• Test objects of all sizes
• Mobile test equipment for running tests at external locations