This case study describes the design and analysis of a support structure for a braking system that was used for a huge flywheel generator. The flywheel generator was designed as a motor generator unit used by the Max-Planck-Institut für Plasmaphysik (IPP) in Garching, Germany, to provide a considerable amount of power for their experiments. IPP is investigating the physical principles underlying a plasma fusion power plant, to produce energy.
Piper Test and Measurement were required to supply a braking system for the flywheel generator. A combination of a hydraulic dynamometer and a water-cooled disc brake was the only possibility as nothing else would have fitted into the building. This braking system allowed the flywheel to come to a standstill in less than ten minutes, without it the generator would have taken a considerable time to slow down and stop. The motor-generator was positioned on a concrete isolation block, connected to the floor of the building by damper elements. As a flexible shaft connection did not exist in the required size through which the new brake could have been connected, the braking system had to somehow be fixed onto the concrete foundation. However, the foundation did not have enough space for the new brake assembly simply to be placed onto it. Therefore, a cantilever supporting structure had to be designed for the braking system, which was to be fixed to the concrete block using some pre-existing holes drilled through the front face of the concrete block. IDAC were required by Piper Test and Measurement to carry out Finite Element Analyses (FEA) to evaluate the design of a support structure for the braking system.