T26.1 - A Thyristor-Based Bidirectional Solid-State Circuit Breaker with Embedded Symmetrical RCD Snubber for DC Microgrid Protection

Thursday, March 26, 2026

8:20 AM - 8:40 AM CT

Location: 214B

Technical Lecture Presenter(s)

Yuxiao Yang (he/him/his)

University of Electronic Science and Technology of China

Presentation Paper

Co-Author(s)

ZW

Zhengxi Wang

University of Electronic Science and Technology of China
ST

Sasa Tong

University of Electronic Science and Technology of China
XL

Xudong Li

University of Electronic Science and Technology of China
HT

Hanbo Tu

University of Electronic Science and Technology of China
WC

Wanjun Chen

University of Electronic Science and Technology of China
Zekun Zhou, PhD (he/him/his)

University of Electronic Science and Technology of China
BZ

Bo Zhang

UESTC

In DC microgrids, conventional MOV-based solid-state circuit breakers (SSCBs) degrade under repetitive surge energy absorption, reducing clamping effectiveness and long-term reliability. This paper presents a thyristor-based bidirectional SSCB (TBCB) with an embedded symmetrical RCD snubber (ES-RCD), in which two capacitors interchange functions between voltage clamping and current commutation according to the direction of energy flow. This functional reuse reduces component count and cost, eliminates MOV-related degradation, and lowers peak thyristor voltage stress. It also prevents surge current reflection at the breaker ports and enables fast re-closing with immediate re-breaking if faults persist. A 400V/4kW laboratory prototype validates the TBCB’s reliable fault-interruption performance under various conditions, demonstrating its effectiveness in enhancing the safety and robustness of DC microgrid systems.