Short circuit fault diagnosis in switches of a single-phase full-bridge inverter

This paper presents a method of short circuit fault diagnosis in switches of a single-phase full-bridge inverter, which feeds an inductive load. To diagnose failures, a current limiter and measurements of the variables were used: control voltages, currents in switches and the load current. With these measurements there were yielded a set of tables. These tables describe the behavior of the inverter. From this set of tables a simplified table is extracted. It includes the minimum information necessary for the establishment of a fault diagnosis. Based on the combinations of their critical information, functions and logic circuits that detect and locate short circuit faults of the inverter were designed. Simulation results confirm the proposed diagnostic method.