Optimizing voltage references in a 3-leg power VSC under single-phase-to-ground faults

Distribution grid deals with several challenges such as the integration of the electrical vehicle, connection of renewable energy resources, management of storage systems, etc. These new factors can often produce some non-desirable effects in the grid such as electrical faults, which can damage the electricity supply quality. In order to improve the supply quality during electrical faults, power converters with specific control algorithms can be connected that modify the voltage on the loads connected to the grid during the duration of the fault. An optimal control can be ensured if a proper estimation of the voltage in the load is carried on. This paper calculates the voltage drop between the output of the power converter and the fault point so as to optimize voltage references in the power converter during single phase-to-ground faults in islanded mode. Simulation results guarantee the successful performance of the proposal. Key words. Smart grids, power converters, electrical faults, islanded mode, distributed generation.