GE’s Power Conversion business has signed a turnkey contract with the Lindoe Offshore Renewables Centre (LORC), a Danish facility for testing renewable energy technology, for the construction, commissioning and handover of what it says is one of the world’s most advanced facilities to test wind turbine nacelles. It will be able to handle output power of up to 10 MW. The Lindoe Nacelle Testing project (LNT) will be located in the Lindø Industrial Park on Funen, and will be ready for first tests in 2014.
The function tester will incorporate GE’s drivetrain, grid simulation, control systems and foundation work. It is comprised of medium-voltage switchgear, transformers, inverter system DDPM (direct drive permanent magnet) motor, HMI (human-machine interface) and foundation. GE will carry out the installation, commissioning and remote service for the project. The medium-voltage inverter system is a further development of GE’s existing MV7000 series and is based on tried-and-tested technology using dynamic control properties and low grid interference.
The new nacelle tester will enable LORC to test the functionality and performance of wind turbine nacelles by using a specially designed adapter that enables the turbine hub and all field operational software and hardware – including pitch control – to be included in the test. It will open up a wide range of opportunities to test wind turbine controllers inside the nacelle, using realistic test conditions at 33 kV level, which is unique in the test system business.
"Users will be able to carry out a full range of tests on their equipment without having to adapt their turbine software or hardware". said Ove Poulsen, chief executive officer at LORC. "Because the test bench can be connected to a ‘virtual’ wind farm (created by a separate system), it will be able to operate as HIL — Hardware in the Loop."
The test bench has a modular design that will enable it to be adapted to future needs. For example, its grid simulator power can be increased at a later date to increase its ability to carry out extended FRT (fault ride through) tests — simulations of wind turbine systems to remain connected to the supply during grid malfunctions and to help stabilize it.
LNT will be able to meet the demand for testing offshore wind turbines in a facility where national grid codes can be tested in combination with loads caused by rapidly changing wind speed conditions. Electrical malfunctions and turbine protection systems have historically led to unforeseen excessive loadings of mechanical components and thereby reduced expected lifetime. At LNT, it will be possible to verify the stress levels under numerous different load cases.