Fault Diagnosis and Reconfiguration for H6 Grid-Tied Inverter Using Kalman Filter

This paper presents an IGBT open-circuit fault diagnosis method based on Kalman filter model and reconfiguration algorithm for H6 grid-tied inverter. This method can detect open-circuit fault by only sampling the inductor current through Kalman filter model. Then, through the reconfiguration algorithm, the H6 grid-tied inverter is reconfigured as a Boost-type converter to identify the faulty IGBT device. The Kalman filter model can also predict the grid voltage provided to the control loop, thus saving the ac voltage sensor for the system. This method does not require extra sensors and diagnostic circuits, so it can be easily embedded in the DC/AC inverter system.