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Hybrid circuit breakers are a class of protection devices to facilitate fault current limitation and fast interruption in AC and DC power systems. They are one of the key enabling technologies of multi-terminal DC transmission and distribution systems. As the power rating of DC power systems increases, mechanical switches in the normal conduction path are chosen to provide low on-state loss in a hybrid circuit breaker topology. These mechanical switches require fast actuation to achieve sub- millisecond switching capability, for which only a few actuation mechanisms have been reported to be suitable. Besides electromagnetic repulsion methods like the Thomson coil, piezoelectric actuators also appear to be a good candidate. This paper provides a survey on potential mechanical switches for hybrid circuit breakers considering different actuation mechanisms. Performances of mechanical switches reported in the literature have been summarized and compared, such as response time, displacement, and required actuation energy.
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A Decentralized Adaptive Scheme for Protection Coordination of Microgrids Based on Team Working of Agents
A decentralized adaptive scheme is proposed for protection coordination of microgrids. In the proposed scheme, a set of agents around the fault location negotiate with each other to reach the best protection coordination strategy upon the occurrence of a fault. Adopting a protective layer, agents are arranged in a number of groups where the members in each group can interact with each other. Considering the operational uncertainties of the respective circuit breakers and communication links, the best fault clearance strategy is determined by analyzing the probability of correct operation of all proposed strategies and considering the least number of probable outages. This is done by calculating the fault currents flowing through the respective circuit breakers and the Latency of the communication links. The efficiency of the proposed scheme is demonstrated by comparing the simulation results of a sample network with those obtained using the conventional central adaptive protection approach.
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- Award ID(s):
- 1650470
- PAR ID:
- 10130891
- Date Published:
- Journal Name:
- International Conference on Renewable Energy and APplications
- Page Range / eLocation ID:
- 1315 to 1320
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/ICRERA.2018.8566886
