Design and Implementation of High Efficiency Control Scheme of Dual Active Bridge Based 10 kV/1 MW Solid State Transformer for PV Application

作者：Liu, Tao; Yang, Xu; Chen, Wenjie; Li, Yang; Xuan, Yang; Huang, Lang; Hao, Xiang

来源：IEEE Transactions on Power Electronics, 2019, 34(5): 4223-4238.

DOI：10.1109/TPEL.2018.2864657

• Dual active bridge (DAB)
• efficiency
• frequency-based analysis (FDA)
• modulation scheme
• solid state transformer (SST)

One promising topology for solid state transformer (SST) is a modular multilevel cascaded converter, in which submodule is composed of dual active bridge (DAB) and H-bridge. For SST application in PV system, the efficiency could be severely affected especially for DAB due to the wide voltage and power range of PV panels. Thus, the motivation of this paper is to deal with the control strategy to improve DAB efficiency inside SST for PV application. Instead of utilizing time-domain based analysis method, which requires complex modeling process, this paper models DAB under frequency domain by fully considering the effect of both fundamental and harmonic frequency component. To achieve high efficiency operation, a multiorder reactive-current suppression (MRS) strategy is proposed by controlling phase shift angle as well as the duty cycles of primary and secondary side Hbridges. In terms of DAB controller design inside SST, the small signal model under MRS is established and a notch filter is implemented to suppress the second order line frequency fluctuation in the control loop. Finally, a 10 kV/1 MW SST prototype is introduced along with the system control structure and implementation method. The experiment of the submodule and SST confirms the effectiveness of proposed method.

• 出版日期2019-5
• 单位西安交通大学