Direct-Current (DC) Arc-Free Circuit Breaker for Utility-Grid Battery Storage System
Funded by NRCan (2012-2016)

Public Report:

English Version

French Version

Abstract:
This report highlights the concept, activities, conclusions and long term outcomes activities of the project ecoENERGY R&D # RENE-005 for the period of October 17, 2012 to March 31, 2016. This project is led by the University of Toronto. In addition to the project leader, three researchers, two graduate students and two Postdoctoral Fellow were the members of the project team.
The main objective of this Project was to research and develop a novel Direct-Current (DC) Circuit Breaker (DC-CB) technology for fast protection and/or isolation of utility-grade battery storage systems.

DC breakers protect and isolate a battery module, in response to internal failure modes and/or EMS (Energy Management System) commands, to guarantee reliable and safe operation of the battery storage system. There is neither a technically feasible nor a commercially viable DC-CB product in the market for battery system applications. In this regard, the developed DC-CB of this R&D project is new and the concept is novel and innovative. The main novelty of this product is the Auxiliary Suppression Circuit (ASC), which actively prevents stresses across electronic switches and prevents arcing of mechanical switches. Another novel aspect of the proposed DC-CB is its modularity, which provides (i) scalability and thus enables applications of different voltage levels based on an optimally designed building block; (ii) ease of maintenance and reduction in down time; and (iii) reduction in space, cost and management of spare parts. It should be noted that the application of DC-CB is not limited to storage and can be directly extended to low- and medium-voltage DC-microgrid systems.

The development of DC-CB eliminates one of the main technical challenges/barriers to the market-acceptance and integration of battery storage as an enabling technology to accommodate high depth of penetration of distributed generation and EV/PHEV in the context of smart distribution systems. This technology will be a key Canadian advantage, providing environmental and economic benefits to Canada. In addition, the University of Toronto will be offering graduate student training, at the Master’s and doctoral levels in research topics related to clean and renewable electricity and the integration of renewable resources and EV/PHEV based on utilization of battery storage systems, thus further developing competitive Canadian expertise in this area.