PCS: Maximum Efficiency when Converting Power from Renewable Energy Sources to Electricity

Nuremberg, October 21, 2013 – Leading power converter manufacturer SEMIKRON, converter developer and manufacturer PCS and the TU Dresden have successfully completed their cooperative research project after three years. Under the heading “More efficient use of regenerative energies with multi-level topologies – EEMT”, the project has resulted in the design of a new type of converter system. The research project was backed by the German Federal Ministry of Education and Research (BMBF) within the framework of the “Power Electronics for Improved Energy Efficiency” initiative, as well as the German government’s high-tech strategy and the “Information and Communication Technology 2020” (ICT 2020) initiative with a total endowment of around € 1.2 million.

During the course of the research project, SEMIKRON was tasked with designing an inverter system with new modular phase components, which would then be integrated into an innovative power converter by PCS. The driver circuitry and protective components were developed by the Electrical Engineering Institute’s Chair for Power Electronics at the Technical University of Dresden.

The original project focused on improving the efficiency of wind turbines applications. However the group was able to significantly expand upon this concept. In the future, these converters could also be used with highly robust drives for raw materials mining, with main drive and onboard power supply systems in rail vehicles, for 1500 V DC overhead lines as well as with solar inverters.

With the innovative converter system created as a result of this initiative, electrical energy that is generated using wind turbines or solar power modules can be efficiently and inexpensively converted for supplying the power supply network. Variable speed drives are an additional possible area of use. In order for the generated power to meet the minimum feed-in quality requirements, standard converters now available in the market require electrical filter switches which result in high loss levels. The multi-level topology applied as part of the EEMT project has resulted in a significant reduction in the role of these filters and the resulting losses. For low-voltage applications that have their own grid connection transformers, such as wind turbines or solar power modules, the voltage level can now be increased to just under the medium voltage level. This approach makes sense because it enables low losses, however it cannot be realized using IGBT converters with a conventional two-point topology. t, By using these more technologically advanced, intelligent three-point phase components, energy efficiency is improved and economic benefits can be realized. Other applications with DC steady-state voltage of over 1300 V already must focus on this kind of switching technology if 1200 V/1700 V standard IGBTs are used.

Communication between the phase components, which are equipped with 3-level IGBT modules, occurs on the basis of a decentralized modulator, which allows for plug-and-play integration in a conventional converter system. A central controller and decentralized phase components are synchronized via serial high-speed EtherCAT data bus connections.

To test the functionality and to check all of the technical features, a 1.0 MW prototype was also created as part of the project.

About SEMIKRON

SEMIKRON is an international manufacturer of power electronics components and systems, primarily in the medium power range (approx. 2 kW to 10 MW). Speed-controlled industrial gears, automation technology, welding systems and elevators are just some of their fields of application. Additional fields include uninterruptible power supplies (UPS), renewable energies (wind, solar) and the electrification of commercial vehicles, forklifts, sports cars and mobile machinery. The family-owned company is headquartered in Nuremberg, Germany. It was founded in 1951 and currently employs 2,900 people worldwide. A global network of 30 operational companies with manufacturing facilities in Brazil, China Germany, France, India, Italy, South Korea, Slovakia, South Africa and the United States guarantees fast and competent on-site customer care.

About PCS Power Converter Solutions GmbH

PCS is an independent, experienced manufacturer of power converters with approximately 240 qualified employees and, most recently, a turnover of 40 million euros. The electrical equipment produced by this Berlin-based company has proven itself more than 70,000 times worldwide – in rail vehicles (PCS Rail), in the field of wind energy generation (PCS Green Line), as well as for the highly dynamic requirements of industrial use (PCS Blue Line). PCS has been developing, producing and servicing electrical equipment for rail vehicles for over 100 years. The PCS Rail division’s product portfolio now includes not only onboard power supply systems, energy supply systems and battery charger units, but also pre-assembled components such as driver’s consoles and electrical cabinets for all types of rail vehicles.

About the Electrical Engineering Institute of the TU Dresden

The Electrical Engineering Institute (ETI) of the Technical University of Dresden is a teaching and research institute specializing in power electronics, drive engineering, and electrical engineering theory and boasts a more than 100-year-old tradition in these fields. The ETI is part of the Faculty of Electrical Engineering and Information Technology, which is one of top research faculties in the area of electrical engineering in Germany.