New LeitDrive 4Q frequency converter to be installed in all Leitwind AG’s wind turbines

LeitDrive is one of the most remarkable innovations resulting from Leitwind AG’s continuous direct drive technology research and development.

The decision to make LeitDrive a standard configuration in Leitwind AG ’s wind turbines follows the successful operation of 5 prototype units in Italy in the course of 2012.

The first new 4Q frequency converters were installed in autumn 2012 in five of the Leitwind AG LTW77 1.5 MW wind turbines in Montecatini, Val di Cecina Tuscany.

LeitDrive is a modular converter offering a power range from 250 kW up to 3.000 kW. In a typical 1.0 MW turbine, Leitwind AG will install four 250 kW LeitDrive converters, each with independent electric circuits. This modular construction means higher availability and productivity since the turbine can continue to operate in the unlikely case of component failure of one converter. Each module is a fully functional unit including a grid and motor side inverter.

The custom made, water cooled power stack allows an extremely compact size of only 400 mm width per module. The simple and elaborate mechanical handling simplifies the service. LeitDrive operates quietly and sits smartly with the generator. The perfect interaction between the generator and the 4Q frequency converter leads to a better optimization of the wind turbine performance. Its’ very compact and modular construction guarantees high efficiency and flexibility.

LeitDrive uses highly efficient, latest generation insulated-gate bipolar transistors (IGBT). “Due to the customized power stack the IGBT selection can focus on the application without compromise, while at the same time avoiding uneconomic over-dimensioning.”, commented Günter Tschinkel, Head of Electrical Engineering.

In order to operate LeitDrive, no installation of cryptic service tools is needed: user access takes place simply by using the built-in web interface. The most common field busses are supported via extension cards. The control algorithm, optimized for Leitwind AG’s own generators, ensures unrivalled efficiency rates.

“Because LeitDrive has been developed and manufactured in house, we can guarantee a perfect service and client support. The LeitDrive is yet another significant milestone is Leitwind AG’s ongoing technology evolution. The knowledge that we have acquired during the development of the direct drive and the frequency converter has opened new technical and engineering possibilities for Leitwind AG ’s R&D”, commented Günter Tschinkel, Head of Electrical Engineering.

Leitwind AG  is one the leading gearless wind turbine manufacturers with a patented synchronous generator using permanent magnets. In just five years, Leitwind AG was able to install over 250 wind turbines worldwide. Almost half of these wind turbines were delivered in 2011 and are followed by further prestigious projects in Italy in 2012.  More than 700 employees work worldwide at the three main company sites in Italy, Austria and India.