Minimum-Output-Current-Ripple Control of Current-Fed Three-Level Phase-Shift Full-Bridge Converter

Abstract

Electrified ports using medium-voltage DC (MVDC) renewable energy microgrids require current-fed dc/dc converters in application scenarios such as battery or ultracapacitor charging units and hydrogen production systems. This paper designs a three-level phase-shift full-bridge (TL-PSFB) converter that interfaces with the MVDC microgrid. Its operation in the current source mode requires a wide output voltage range and small output current ripple. Firstly, the dual-output TL-PSFB topology is introduced, and the principle of phase-shift pulse width modulation (PS-PWM) is presented. Secondly, the principle of the traditional constant-conduction-duty-cycle (CCDC) strategy is analyzed. Then, a minimum-output-current-ripple (MOCR) strategy is proposed by analyzing the relationship between output current ripple, conducting-duty cycle, and phase-shift duty cycle, and a constant current control combined with the MOCR strategy is designed. The output current ripple of the MOCR strategy is smaller than that of the CCDC strategy in a full range of operating conditions. Under the same output current ripple design index, the value and loss of the filter inductor can be reduced with the MOCR strategy. In addition, the MOCR strategy can widen the output voltage regulation range and increase the bus voltage utilization without causing significant changes to the total harmonic distortion (THD) of primary voltage. Finally, experimental results verify the correctness of the theoretical analysis.

Phase Shift APOD and POD Control Technique in Multi-Level Inverters to Mitigate Total Harmonic Distortion

“…S1 and S2 only contribute when the output voltage is produced in the positive half cycle, while S3 and S4 contribute when the output voltage is generated in the negative half cycle. Below is a list of all switches and associated switching tables [26].…”

A Novel Second Harmonic Voltage Suppression Control for PSFB Converter in Dual-Stage Single-Phase Rectifier

“…As global concerns about rising fossil fuel prices and the urgent need to address climate change intensify, dual-stage single-phase rectifiers have garnered significant worldwide attention [1][2][3][4][5]. Among these rectifiers, the phase-shifted full-bridge DC-DC (PSFB) converter stands out as a crucial component in the subsequent stage due to its remarkable efficiency and unique galvanic isolation properties [6][7][8][9]. However, a significant challenge arises from the pulsating input power of the front-stage single-phase power factor corrector (PFC).…”