A study of electric double layer capacitors improving electric network voltage fluctuation for urban railway transit

This paper presents a state-averaged model and an effective control method of a regenerative power storage system to save energy and improve electric network voltage fluctuation in urban railway transit. The regenerative power is stored and then provided to a traction motor by the storage system that consists of an electric double layer capacitors (EDLC) and bi-directional DC/DC converter. We have designed a new control system using voltage and current control mode to achieve the stability and the quick response. The utility of the proposed method is examined through computer. Finally, we constructed an experiment equipment, which contains diode bridge rectifiers, a bi-directional DC/DC converter, EDLC and PWM inverter.