Controller Hardware-in-the-Loop Validation of a Modular Control Architecture for a Composite DC-DC Converter

This paper presents a modular control architecture for a composite dc-dc converter topology. A composite converter comprises multiple dissimilar partial-power converter modules arranged and operated to minimize stresses and improve system efficiency over a wide range of operating points. This requires transitioning to different operating modes for different operating conditions. A control strategy is required to determine the optimal mode, and to achieve smooth mode transitions and fast closed-loop system dynamic responses. A modular control architecture capable of meeting these objectives is described. In this architecture, low-level module controls are decoupled from system-level operations. The resulting hierarchical control strategy is relatively simple, and highly scalable in nature. The approach is developed and validated on a controller hardware-inthe-loop (CHIL) platform. A frequency scaling strategy is applied to allow validations of high-switching frequency converters on bandwidth-limited CHIL platforms.