Microgrid Reliability Analysis Under Distributed Degradation of Semiconductor Power Switch Modules Through a New Stochastic Hybrid System Modeling

摘要

This paper presents a novel approach for reliability evaluation of an AC microgrid by integrating the power semiconductor switch degradation in the converters. DC/DC and DC/AC converters are extensively used in a microgrid as they integrate the renewable energy sources and battery storages with the system. Semiconductor switches utilized in these converters have a significant impact on the system level performance. These switches directly interface the distributed renewable energy generators within a microgrid system which are commonly designed with lower controllable margin due to ever increasing power and energy demand. Failure of semiconductor power switches is one of the most common faults in the microgrid which can lead to reduction of the microgrid's reliability. In this paper, to couple the semiconductor power switch degradation with the overall microgrid system reliability, System Average Interruption Duration Index (SAIDI) is evaluated under different combination of power converter semiconductor switch degradation. Stochastic Hybrid System (SHS) approach is utilized to model the microgrid to consider the uncertainties in renewable energy sources. The SHS model is then correlated with SAIDI. This fact supports to validate the dependency of microgrids reliability on component level performance.