Impedance-based stability analysis and design considerations for DC current distribution with long transmission cable

TitleImpedance-based stability analysis and design considerations for DC current distribution with long transmission cable
Publication TypeConference Paper
Year of Publication2017
AuthorsWang, H., T. Saha, and R. Zane
Conference Name2017 IEEE 18th Workshop on Control and Modeling for Power Electronics (COMPEL)
Date Published07/2017
Conference LocationStanford, CA, USA
ISBN Number978-1-5090-5326-1
Accession Number17122079
Other NumbersPrint on Demand (PoD) ISBN: 978-1-5090-5327-8
KeywordsAnalytical models, capacitance, constant current input, control design, converter closed-loop input impedance, converter open-loop input impedance, current 1 A, current distribution, DC current distribution systems, dc distribution, dc distribution systems, dc voltage distribution systems, design considerations, Impedance, impedance expressions, impedance-based stability analysis, inductors, long transmission cable, Nyquist plot, power 500 W, Power cables, power converter stability, power distribution, power system stability, power transmission lines, regulated output current, resonant power convertors, series resonant converter, SRC, Stability analysis, system minor loop gain, transmission, voltage distribution

Stability is a major concern for dc distribution systems because the integrated system may become unstable even though the subsystems are stable individually. Significant analysis and design has been applied to dc voltage distribution systems, while stability and related control design are not well studied for dc current distribution systems, especially for the scenarios with long transmission cables. In this paper, impedance expressions for long transmission cables are derived and applied to analyze stability of power converters in dc current distribution systems. The relation between converter closed-loop and open-loop input impedance is discussed by taking a series resonant converter (SRC) with constant current input and regulated output current as an example. Impedance-based stability analysis and design considerations are proposed by employing the Nyquist plot of the system minor loop gain. The stability analysis and design presented are validated through experimental results based on a system with a 1 A current source, a 100 km cable emulator and a 500 W SRC.