A Purely Decentralized Control System Based on Cascaded Power Electronic Traction Transformer

The cascaded power electronic traction transformers (PETT) based on neutral-point-clamped converter (NPC) and dual-active-bridge (DAB) has the advantages of small size, light weight, and high efficiency, which fully meets the development needs of lightweight, intelligent, and comfortable high-speed railway in the future. However, the problems of centralized control and quasi-distributed control such as heavy burden of master controller and poor failure protection are serious. A purely distributed control system based on cascade PETT is proposed in this paper, which completely distribute the algorithm in each submodule and has no single point of failure. The feasibility and stability of the control system are verified by simulation.