# A High-Conversion Ratio Multiphase Converter Realized with Generic Modular Cells
## 1 Introduction
This work presents a full architecture analysis and generalization of a series-capacitor buck to higher orders, increasing both the conversion ratio and current output capabilities. In addition, this work covers advanced topics and analyzes those such as soft charging, boundary operation, voltage versus duty cycle evaluation, component stress analysis, and a modularization method using a generic cell. From a design perspective, many power converters can be analyzed as being constructed around a fundamental cell [10; 45; 46; 47]. This fundamental cell enables the implementation of several different topologies, which share a mode of operation and provide various conversion ratios by reconfiguring its connection orientation. For instance, common converter topologies such as buck, boost, and buck-boost share a core structure comprising a single inductor and two switches [48; 49; 50]. Despite utilizing the same basic components, these converters achieve different functionalities through distinct topological arrangements. A power design methodology based on a fundamental cell provides numerous advantages, including modularity, which simplifies the design process and supports easy scalability. It promotes standardization, reducing design complexity while ensuring consistent performance across various applications. This approach enhances effectiveness by enabling component reuse, minimizes development time, and streamlines validation and testing efforts. Furthermore, it improves manufacturability by maintaining uniformity during fabrication and reduces costs through shared design and testing efforts, making it a highly effective strategy for power system development. The objective of this study is to introduce a modular construction approach of a very-high conversion ratio multiphase converter, based on a generic, switched _LC_ cell. The converter (Figure 1) is constructed from a chain of identical building blocks, each consisting of a switched inductor-capacitor pair that forms a stacked series-capacitor converter frontend whereas the backend of the converter is a set of parallel or interleaved inductors. This modular stacking of generic cells allows flexibility in the design, enabling high-power and high-conversion ratio without sacrificing the end-to-end efficiency of the converter, since the operation relies on single-cycle power processing from source to load, regardless of the number of modules stacked. Current sharing is maintained throughout the multiphase backend, allowing state-of-the-art performance in terms of power considerations and converter sizing for operation in both steady-state and transient modes. The rest of the paper is organized as follows. Section 2 presents the operation principle and the construction methodology of modular stacking of identical switched inductor-capacitor cells. In Section 3, a full steady-state analysis of a three-level converter is delineated. The generalization of voltage and power stacking is analyzed in Section 4. Simulation and experimental results are provided in Section 5, and Section 6 concludes the paper.