Defining and Constraining the Electrical Cardinality of Multiport Converter Mission Profiles

TL;DR

This paper introduces the concept of electrical cardinality in multiport converter mission profiles, showing how constraining it can simplify designs while maintaining performance in distribution systems.

Contribution

It defines electrical cardinality for multiport mission profiles and demonstrates how to constrain it within optimization, enabling simplified converter reconfiguration.

Findings

Reducing cardinality from four to two still supports congestion management.

Achieves 91.7% of loss reduction compared to conventional designs.

Demonstrates practical application in distribution system scenarios.

Abstract

Mission profiles describe a representative set of conditions that a power converter is designed to operate under, and are known to be more complicated for multiport converter applications due to a wider range of combinations of powers that can be transferred between ports. This paper studies the properties of mission profiles derived from operational optimization of multiport converters in distribution system applications (e.g., soft open points). The electrical cardinality of the mission profile is introduced as a useful, naturally varying property of multiport mission profiles derived from optimal operation within distribution system, with the cardinality equal to the number of non-zero power transfers at a given time. Furthermore, it is shown that the cardinality can be conveniently constrained within the framework of conventional mixed-integer conic optimization problems, yielding a family of mission profiles that can enable converter designers to simplify multiport designs via converter reconfiguration. Results demonstrate the potential to reduce the cardinality in a four-terminal multiport converter from four to two whilst still effectively supporting congestion management and achieving 91.7% of the loss reduction capabilities of a conventional design.