2023 article

Bidirectional Three-phase Current Source Converter based Buck-boost AC/DC System using Bidirectional Switches


By: R. Narwal n , S. Bhattacharya n , B. Baliga  n & D. Hopkins n 

co-author countries: United States of America πŸ‡ΊπŸ‡Έ
author keywords: Bidirectional switches; four-quadrant switches; current source inverter; interleaved buck converter; modulation; commutation; SiC bidirectional FET; BiDFET; CSI; CSC
Source: Web Of Science
Added: October 10, 2023

The 1.2 kV 4H-SiC BiDirectional Field Effect Transistor (BiDFET) is the first monolithic SiC bidirectional switch, which offers a lower voltage drop and semiconductor devices count alternative to the reverse-voltage-blocking (RB) switch used in the current-source converters (CSC). The bidirectional switch based CSC also allows DC-link current reversal for bidirectional power flow and provides multiple system-level benefits in a buck-boost AC/DC system consisting of buck-type DC/DC converter and CSC. This paper discusses the selection of buck converter duty cycle and CSC modulation index for the system's buck-boost operation with a wide variation in DC voltage. CSC modulation schemes categorized based on the number of hard-turn-on transitions per switching cycle are also analyzed along with the three-step and four-step commutation schemes that are essential for the CSC commutation cells. Finally, the different schemes are evaluated and compared through the experimental results of a 10 kW, 480 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{V}_{\mathbf{RMS},\mathbf{LL}}/$</tex> (400 - 800) V AC/DC system.