Design approaches for fast supercapacitor chargers for applications like SCATMA, SRUPS

The proliferation of electric vehicles (EV) creates a need for fast battery chargers. In order for systems of supercapacitors (SC) to reach adequate energy density levels to replace battery packs, fast SC chargers will also be required. However, when a fully discharged supercapacitor pack is charged from an ideal voltage source, the five-time-constant charging bottleneck comes into play. This issue can be addressed by using the high-voltage charging topology proposed here. The new approach partitions the SC bank into two parts. One part is charged by a high voltage charging source, and the other is replenished by the energy stored in a coupled inductor within the charging path used for the first half of the bank. Early experimental results for a 30 V, 15 F SC bank are presented.