<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>A 4-level flying capacitor converter (FCC) operation is considered on a base of discrete state-space model. A transition matrix is obtained for a pulse width modulation (PWM) period for small normalised voltage command values [0, 1/3]. The transition matrix elements are expanded into power series by small parameters. The matrix eigenvalues are presented in the form of power series as well. Six separate transients are constructed for six possible initial FCC states on a PWM period. Inductor current and capacitors’ voltage transients are found for the voltage source power-up as the arithmetic average of the six separate transients. Finally, the discrete solutions are replaced by equivalent continuous ones. Simple and accurate formulas for inductor current and capacitors’ voltage transients demonstrate good agreement with simulation results.</p>
</abstract>

A 4-level flying capacitor converter (FCC) operation is considered on a base of discrete state-space model. A transition matrix is obtained for a pulse width modulation (PWM) period for small normalised voltage command values [0, 1/3]. The transition matrix elements are expanded into power series by small parameters. The matrix eigenvalues are presented in the form of power series as well. Six separate transients are constructed for six possible initial FCC states on a PWM period. Inductor current and capacitors’ voltage transients are found for the voltage source power-up as the arithmetic average of the six separate transients. Finally, the discrete solutions are replaced by equivalent continuous ones. Simple and accurate formulas for inductor current and capacitors’ voltage transients demonstrate good agreement with simulation results.

Analysis of Transients in a 4-Level Flying Capacitor Converter: Time Domain Approach. Part 2: Small Normalised Voltage Command

Department of Electrical and Computer Engineering

State University of Aerospace Instrumentation

Power Electronics and Drives

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

A 4-level flying capacitor converter (FCC) operation is considered on a base of discrete state-space model. A transition matrix is obtained for a pulse width...

Analysis of Transients in a 4-Level Flying Capacitor Converter: Time Domain Approach. Part 2: Small Normalised Voltage Command

Published Online: Oct 10, 2020

Page range: 41 - 57

Received: Oct 03, 2019

Accepted: Jan 05, 2020

DOI: https://doi.org/10.2478/pead-2020-0003

Keywords
4-level DC–DC converter, flying capacitor, natural balancing, transients

© 2020 Boris Reznikov et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Analysis of Transients in a 4-Level Flying Capacitor Converter: Time Domain Approach. Part 2: Small Normalised Voltage Command

Published Online: Oct 10, 2020

Page range: 41 - 57

Received: Oct 03, 2019

Accepted: Jan 05, 2020

DOI: https://doi.org/10.2478/pead-2020-0003

Keywords4-level DC–DC converter, flying capacitor, natural balancing, transients

© 2020 Boris Reznikov et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
4-level DC–DC converter, flying capacitor, natural balancing, transients