Grid Load Mitigation in EV Fast Charging Stations Through Integration of a High-Performance Flywheel Energy Storage System with CFRP Rotor

Increasing the share of battery electric mobility in
the transport mix, while at the same time integrating more
renewable volatile energy sources in the grid, brings along a
variety of challenges such as possible power quality, voltage and
grid stability issues. Deploying decentralized energy storage
devices in electric vehicle (EV) fast charging stations as buffer
storage is one way to mitigate these problems and help store
renewable energy in the grid. This paper describes a system
integrating a high performance flywheel energy storage system
(FESS) in a fully automated fast charging station. A holistic
approach is pursued, determining the FESS’s energetic target
properties by analyzing user behavior in a variety of use cases in
conjunction with in-depth grid simulations. Based on these data, a
FESS design is proposed and approaches to reach the desired
energetic target properties are discussed. Critical components are
presented with a focus on CFRP rotor design, as it is crucial for
achieving the required energy content at lowest specific cost.