PV-PACK RESEARCH PROJECT SUCCESSFULLY COMPLETED: REDUCING COSTS IN PHOTOVOLTAICS WITH NEW HIGHLY INTEGRATED INVERTER CONCEPTS
SMA Solar Technology AG (SMA), the Fraunhofer Institutes for Solar Energy Systems ISE and for Manufacturing Technology and Advanced Materials IFAM, and Phoenix Contact GmbH & Co. KG have completed the PV-Pack research project that focused on inverter concepts after three years of successful collaboration. The goal of the project was to develop alternative solutions in cooling and structure and connection technologies, characterize new materials and optimize these concepts in interactions with inverter system power electronics. With the project results achieved, significantly more compact and cost-effective PV inverters will be possible in the future. The collaborative project was backed by around €1.4 million from the German Federal Ministry of Education and Research (BMBF) as part of its “Power Electronics for Improved Energy Efficiency (LES) Part 2: Electronics for the Energy of the Future” initiative. SMA was responsible for coordinating the project.
Technologically, inverters are the most important components of PV systems. They determine the efficiency and reliability of the entire system. To further strengthen the international competitiveness of the German photovoltaic industry, the technology used in inverters must be continuously improved while innovations in a wide range of relevant areas are also needed to expand the technological advantage of the industry. Today, mechanical and electromechanical components of connecting, supporting and cooling structures make up 70% of a PV inverter. The goal of the PV-Pack research project was therefore to deal specifically with these elements of structural, connecting and cooling technology to facilitate significantly more compact and cost-effective PV inverters by means of new technologies, materials and optimization methods.
In the close collaboration between science and industry, a wide range of innovations were developed within the context of PV-Pack, and evaluated in a 50 kW technology demonstrator as well as an inverter experimentation platform with innovative silicon carbide semiconductor components. With new approaches to technology and methods, efficient ways for doubling the power density while also considerably reducing costs and maintaining the tried-and-tested SMA device reliability were successfully demonstrated. Initial partial results of the project, such as the innovative device structure concept, will be incorporated into series-manufactured solar inverters from SMA as early as this year. The knowledge gained about new technological approaches and methodology, and how these can be optimally combined, constitute an important foundation for further preparatory research and future series products created on this basis.
The project has impressively shown that, particularly in mechanical-thermal optimization based on new materials and technologies, there is still considerable untapped potential for further development and the urgently required cost reduction in inverter technology. In addition, the compactness and performance of the devices can again be considerably increased through the use of new silicon carbide components. This, coupled with the new technological solutions created in the project, was evidenced through the resulting fully-functional laboratory inverter. The outcomes achieved in the interdisciplinary PV-Pack research project will thus help German industry stand its ground against increasingly tough international competition and maintain Germany as a production site.