Bidirectional three-phase high-frequency ac link dc–ac converter used for energy storage

In this study, a bidirectional three-phase high-frequency ac link dc-ac converter is proposed for energy storage with low dc voltage. The operation of the converter changes with the direction of power flow. The proposed topology has the following advantages: high voltage conversion gain, high power factor, high conversion efficiency and high power density. The operation principle of the general control strategy, mode analysis and gate signals generation are discussed. The proposed architecture and the general control strategy have been validated by experimental results of a 300 W laboratory prototype using supercapacitors as the storage device.