Skipped Adjacency Pulse Width Modulation: Zero Voltage Switching over Full Duty Cycle Range for Hybrid Flying Capacitor Multi-Level Converters without Dynamic Level Changing

TL;DR

This paper introduces a skipped adjacency PWM method that achieves zero voltage switching across the full duty cycle range in hybrid flying capacitor multilevel converters without dynamic level changing, improving efficiency.

Contribution

The paper presents a novel SAPWM technique enabling full-range ZVS in hybrid FCML converters without dynamic level adjustments or active re-balancing.

Findings

Achieves full-range ZVS in simulations

Reduces switching losses and improves efficiency

Compatible with various levels of hybrid FCML converters

Abstract

This paper proposes a method to achieve zero voltage switching (ZVS) across the full duty cycle range in hybrid flying capacitor multilevel (FCML) converters, eliminating the need for dynamic level changing and active re-balancing. Utilizing skipped adjacency pulse width modulation (SAPWM), this approach avoids the nearest pole voltage level, thereby increasing volt-seconds within specific duty cycle range. The method uses a modified PWM scheme, which preserves effective pole voltage by changing duty reference and employing digital logic processing. Simulation results verify the proposed method achieving full-range ZVS. This SAPWM technique is compatible with hybrid FCML converters with various levels, offering enhanced efficiency and reduced switching losses.