Redundant & Efficient DC/DC System for Electromobility

According to the data from Credit Suisse Global Auto Research team, production of the Electric Vehicles (EVs) is expected to rise from 11% in 2020 to 62% in 2030, come to a head at 63 million vehicles worldwide. As EVs are moved from niche to mainstream, governments and municipalities are trying to find sustainable ways of transportation that can match mobility needs and reduce environmental harm. Autonomous Mobility-on-Demand (AMoD) systems hold promise as a future mobility concept in urban environments, composed out of fleet of robotic, self-driving vehicles co-exist in the existing infrastructure, in a more efficient way. Soon to follow up are applications in the fields of agriculture, industry, airport and railway, as the price of implementation will be reduced, enabling return of investment in reasonable amount of time.
Increase in demand and continuous updated CO2 emission compliance standards have stimulated different OEMs to reconsider key aspects of how to power the electromobility again, however a harmonized approach for delivering electric power, not only to the motors but to all the subsystems in a vehicle has not emerged. The lack of direction is obviously amplified by the tremendous increase in power requirements and system reliability, as legacy electrical subsystem in combustion engine vehicles operates within power levels between 600W to 3kW. In today’s EVs low voltage (LV) on-board power supply exceeds power levels of 3kW, especially when considering power requirements of the autonomous driving systems. It is evident that 5 – 20x increase puts tremendous strain on complexity of the LV on-board power supply system. These demands negatively impact energy efficiency but especially reliability of the EVs, which could be considered critical in AMoD systems, implying need for new architecture designs.
This project research focus is directed towards investigating novel concepts and architectures for safe, reliable & efficient energy distribution in electromobility HV to LV on-board power supply system. Within the framework of industrial research, the aim of this project is to investigate and evaluate concepts for safe, reliable & efficient low voltage (LV) on-board power supply system, develop technical components of the power supply system and bring them together in the form of a demonstrator. This includes:
· Develop novel HV to LV on-board power supply system architecture having in mind high availability & redundant system supply.
· High availability requires multiple-input power electronic converter – a magnetic integration concept is planned to be used instead of increasing the number of the modules, therefore reducing size and weight of the power module. Further integration of different components and functions will be also investigated.
· Redundancy requires a safe disconnect function – a new system concept to use semiconductor switches instead of mechanical relays – further reducing size and weight.
Concepts will be evaluated for specific use conditions, for the application which requires highest reliability supplying all critical vehicle components – safety relevant or long usage vehicles. Proposed realizations will be evaluated on the merits of reliability and efficiency, bearing in mind the tradeoff between reliability and added size and weight. Additionally, comparison will show if the concept could have potential to replace the low voltage battery, reducing weight and improving overall efficiency of the EVs.