| Project Detail |
Today’s power grid relies primarily on alternating-current (AC) electricity as opposed to direct-current (DC). DC has advantages over AC such as lower distribution losses, higher power carrying capacity, and reduced conductor materials, which make it well suited to industrial applications, transportation, and energy production. However, the risk associated with electrical faults, such as short circuits, and system overloads, continues to hinder the growth of DC markets. Inherently, AC electricity periodically alternates direction, providing a brief “zero crossing,” where no current flows. This characteristic allows electrical faults to be interrupted by conventional electro-mechanical breakers. DC networks deliver power without zero crossings, which make conventional circuit breakers ineffectual in fault scenarios. To fully benefit from medium voltage (MV) DC usage, fast, highly reliable, scalable breakers must be developed for commercial deployment.
Project Innovation + Advantages:
Drexel University is proposing a solid-state MV circuit breaker based on silicon carbide devices, a resonant topology, and capacitive wireless power transfer that aims to significantly improve breaker performance for the MVDC ecosystem. The project combines innovations in using an active resonant circuit to realize zero-current switching, wireless capacitive coupling between the conduction and breaker branches to avoid direct metal-to-metal contact for rapid response speed, and wireless powering to drive the MV switches for improved system reliability.
Potential Impact:
The proposed breaker is installed close to loads to rapidly detect and react to the short-circuit fault. Thus, it could enable an increased number of electronic loads that operate using DC, such as ultra-fast electric vehicle charging stations and utility scale energy storage battery units, to connect to the MV distribution grid. This would improve overall power delivery efficiency. |
