Expeditious Identification of IGBT Switch Fault in Bidirectional Microgrid Inverter Linked to Distributed Energy Resources

Abstract

In contemporary power electronics, Insulated Gate Bipolar Transistors (IGBTs) are extremely important for various reasons. IGBTs serve as vital components in microgrid inverters, providing the switching capabilities required to transform DC electricity from renewable sources into high-quality AC power for microgrid (MG) applications. A bidirectional inverter (BDI) is an essential component of a microgrid, allowing for the smooth integration of distributed energy resources (DERs) and supporting both gridconnected and islanded operations. In a bidirectional DC/AC inverter (BDAI), IGBTs play an important role in managing the flow of electricity in both directions. The consequences of bidirectional inverter's IGBT failures on a microgrid might vary from small power quality concerns to more serious interruptions in stability and system performance. Therefore, IGBT should operate without failure. This paper illustrates a method for identifying an early IGBT switch failure (ISF) in a bidirectional microgrid inverter that is linked to a photovoltaic (PV) and battery energy storage system (BESS). An analysis of the inverter output current signal using the Fast Fourier Transform (FFT) has been undertaken to discover faults. Afterwards, the impacts on the DC, fundamental current component, and harmonic distortions have been investigated for various levels of fault. A successful detection of the ISF has been attempted, based on the best-fit features. An ISF detection algorithm also has been proposed.