IISB-ONE Electric Test Vehicle

The Erlangen Fraunhofer Institute for Integrated Systems and Device Technology IISB presents its electric sports car "IISB-ONE", an open for adjustments test vehicle for power electronic vehicle components. Builds in particular by the Project Objective Target Straßenzulassung the Institute its system competence in the field of electromobility further. For the realization of the electric powertrain systems were exclusively developed for use on IISB. The modular vehicle concept allows flexible integration of future developments.

For over ten years, Fraunhofer IISB developed power electronic components for battery and hybrid electric vehicles. The portfolio includes electric drive systems, integrated converter, insulating and non-insulating DC / DC converters and chargers and battery storage systems. In order to test these components in composite and under practical conditions, now the testing and demonstration vehicle "IISB-ONE" was presented. The vehicle is based on a chassis of the previous company Artega and is exclusively equipped with IISB components. These have been developed in various research projects and in cooperation projects with the automotive industry.

Through extensive component and vehicle testing, and compliance with relevant standards and regulations, the project aimed at the street legal "IISB-ONE" was achieved. The aim was not just to build a functioning vehicle, but also to provide a flexible research platform for everyday use. Scientists at the Fraunhofer IISB use the findings to build upon the existing system competence in the field of power electronic vehicle components and battery systems for electric vehicles further.

The vehicle-mounted integrated traction drive has been realized by the Fraunhofer IISB within the BMBF-funded joint research project FSEM. The system is characterized by two mechanically independent single wheel with integrated dual inverters and separate field-oriented control of the two electric motors. This makes possible a free distribution of torque to both drive wheels of the axle. In total, per wheel drive power of 80 kW and a peak torque of 2,000 Nm. The fully integrated in the drive power electronics reduces both space requirements and the costs and results in a significantly improved EMC performance. The power electronics uses novel first intelligent Umrichterbausteine. These eliminate many conceptual weaknesses of today's power modules.

The high-voltage electrical system of the IISB-ONE follows the institute's approach of a flexible, intelligent and secure energy deployment in electric vehicles. Centerpiece here is a work based on lithium-ion cell battery system with 355 V rated voltage. Developed at the Institute integrated battery management ensures reliable operation. The modular internal system design allows adaptation to a wide range of energy storage power, energy and vehicle classes.
A DC-DC converter 3.5 kW replaces the traditional alternator in the car and supplies the 12 V power supply-to-touch from the high-voltage battery. A non-insulative high-performance DC-DC converter provides the drive system in dependence on the driving state always the optimum operating voltage. The system is also open to the future inclusion of other energy storage, whether, for example, is an additional battery or a fuel cell.

The "IISB-ONE" is prepared for testing and demonstration of various contactless and cable-based charging technologies. An integrated in the energy storage proprietary AC charger allows a flexible "refueling" both at public charging stations as well as at any power outlet with up to 3.7 kW. The integrated high-performance DC-DC converter is also a DC quick-charging function of cost, since unregulated DC charging stations provided.

The highlight is an inductive charging system on the vehicle front, with a contactless charging of IISB-ONE with up to 3.5 kW is possible. The system is characterized by highest user comfort, a high position tolerance, low cost, high security and high charging efficiency of up to 97% off at a weight of only 3 kg.

Flexible vehicle control concept simplifies component integration
The integration of subsystems into a reliably functioning vehicle is due to the variance of available communication interfaces and protocols, a real challenge. For this reason, an adaptive vehicle control was developed at IISB which a simple communicative linking different (prototype) systems into an overall -Vehicle allows. An additional software abstraction layer makes this the individual control units for the user to handle. The vehicle control system coordinates and monitors the Antriebstrang- and energy storage systems, ensuring at all times a safe vehicle operating state.
The Fraunhofer IISB provides comprehensive research and development services for power electronic vehicle components. Beginning of system studies to the realization of prototypes for research vehicles of major OEMs the complete range is covered. Since the Institute the entire value chain of the chip processing on electronics and software development, mechanical design is available to system characterization and testing, the Fraunhofer IISB is able to offer its customers even very complex system solutions from a single source.

Source: IISB press

Gallery: IISB-ONE Electric Test Vehicle