Independent power decoupling method using minimum switch devices for single-phase current source converters

摘要

Independent power decoupling (IPD) topologies are used to mitigate the twice-line-frequency ripple power in single-phase systems. Then, bulky passive capacitors or inductors can be removed. This paper proposes an improved IPD topology for single-phase current source converters (SCSCs) to remove the bulky DC rail inductor. It only adds one active switch and one diode. When compared with existing IPD circuits, the required switch devices are minimum and control is flexible. In addition, due to the fact that two identical capacitors are used to buffer the ripple power, the buffer capacitor voltage stress and DC current ripple are significantly reduced. This paper introduces the operation mode and switching states of the proposed topology. Then, the modelling and control strategy are introduced. Moreover, the designs of the passive components are presented. Finally, the effectiveness of the proposed topology is verified by constructing a low-power experimental prototype.