Feedforward control of parallel resonant DC-DC converter with capacitor input source

Double-layer capacitors, with their high energy storage capability, may be utilized to supply peak power requirements in systems such as electric vehicles. As energy is drawn from a bank of double-layer capacitors, the voltage at the terminals of the capacitor bank decreases. Seventy-five percent of the initial energy stored in the capacitor bank can be utilized if the voltage is allowed to decrease to one-half of its initial value. The capacitor bank can be augmented with a DC-DC power converter to present a constant voltage to an external system as the capacitor bank voltage decreases. This paper describes the design and control of a parallel resonant power converter to be utilized with a double-layer capacitor bank. Regulation of the power converter output voltage as the capacitor bank voltage decreases is achieved through a feedforward of the capacitor voltage and the feedback of the power converter output voltage. Operation of the power converter with a capacitor bank has been verified through simulation with Simulink and experimentally in a 12 V laboratory system.