Power Decoupling Technique for Reducing DC-Link Capacitor of Switched Reluctance Machine Drive

Switched reluctance machine (SRM) imposes a high ripple in the battery current which increases the size of the dc-link capacitor and reduces the power density of the system. This paper presents a power decoupling technique to reduce the dc-link capacitor of SRM drive. A bi-directional cascaded buck boost (CBB) converter is used in parallel to the SRM drive to filter the ripple current with the use of low dc link capacitors. The proposed converter processes the partial power to decrease the size of the drive without having any effect on the machine's performance. This converter requires reference current for the inductor generated from the switching sequence of the main SRM drive. State variable feedback with integral controller is used to control the converter. Simulation results are provided to show the validity of the proposed method.