Dynamic Modeling, Simulation and Control of Hybrid Energy Storage System Based on Compressed Air and Supercapacitors

In this paper, the dynamic modeling and the control design of hybrid energy storage system based on compressed air and supercapacitors (CAES-SC) is presented, which converts excess energy from the power supply to stored pneumatic energy by using a compressor. Efficient charging and discharging of the device is performed under maximum power conditions, so that the machine speed is adjusted for this requirement, and the energy delivered to the power system is controlled through an intermittent operation of the pneumatic converter. In order to smooth the desired output power of the system, a supercapacitors bank (SC) is utilized. In this context, power electronics and its control play a significant role in the integration of the CAES-SC system into the network. The dynamics of the power conditioning system (PCS) and the hybrid energy storage unit with SCs (SCES), affect the validity of the CAES-SC system for power system dynamic control, allowing controlling the energy exchange between all devices. The dynamic performance of the proposed systems is evaluated by digital simulation in SimPowerSystems of MATLAB/Simulink.