A Layered Modular Controller Structure for Multilevel Converters

Multilevel converter topology is considered to be one effective solution for high power applications. However cost, size and reliability limit its widespread implementation. The industrial demands for efficient and reliable power converter controllers give rise to modularized converter and controller design. In this paper, a layered model, which is inspired by the layered model in computer network, is introduced to the design of power converter controller structure. A local controller is developed to be integrated with the power converter and thus forms a new converter layer with intelligent functions including feedback and self-protection. The proposed controller structure is validated in a three phase STATCOM system. The experimental results prove the feasibility of this proposed modular controller structure.