Energy storage is key topic for sustainable development gaining more and more attention in research, industry and power grids. However, any available technology (batteries, fuel cells, flywheels and so on) can cover a limited part of the power-energy plane, known as Ragone Plot, and is characterized by some inherent drawbacks. Supercapacitors (also known as ultracapacitors, double layer capacitors, pseudo capacitors or electrochemical capacitors) are a relatively new class of devices characterized by high values for the specific capacitance, even orders of magnitudes higher than traditional capacitors. This allows using supercapacitors as effective energy storage systems offering a trade-off between the high specific energy of batteries and the high specific power of traditional capacitors, opening the way for new performances and applications.
One of the main problem in exploiting supercapacitors is the difficulty to define an accurate and comprehensive model of their behavior in the different situations. The presentation introduces the approaches and the parameters available to model circuits including supercapacitors. However, instead of presenting a general model and method, the problem is approached by a specific application: the calculation of the optimal size and configuration of an energy storage system for a complex load, as a required in a large experimental facility for the study of nuclear fusion reactions. The facility operations are based on power converters (H-bridge inverters) for arbitrary currents exceeding 30 kA and including energy recovery. The design optimization is performed by PSIM simulations including Renewable Energy module.
Dr. Alessandro Lampasi