PWM Based Sliding Mode Control of a fast charger for supercapacitors

The paper deals with the design and control of a fast charger circuit for Energy Storage Systems based on supercapacitor. The proposed solution finds natural application in the recharge stations of electrical vehicles (e.g., electrical buses, forklift, etc.) typically alternating short runs to periodic stops. It performs the charge migration from a module to supercapacitors to another, following a constant current profile to minimize the charging time. The control law, designed to be implemented in a commercial microcontroller, exploits a sliding mode technique properly modified to operate in PWM mode. Numerical simulations in MATLAB/SIMULINK environment with SimScape have been performed to prove the effectiveness of the proposed control.