DC bus voltage balancing of multi-inverter in photovoltaic system

Solar energy is a type of renewable resource, which is simply defined as any supply that occurs naturally within the environment, and can be replenished over time. In PV solar system dc-ac conversion is one of the important components; a five level neutral point clamping voltage source inverter NPC (VSI) converter is used. This paper presents a control system for a three phase five-level NPC connected to grid in photovoltaic (PV) system with storage. The maximum power point tracking (MPPT) is capable of extracting maximum power from the photovoltaic (PV) array connected to each DC link voltage level through DC-DC converter. For DC link voltage control, we proposed neuronal regulation with introducing clamping bridge circuit; it is needed to stabilize the voltage of the inverter input to insure a continuous flow of energy between the grid and the PV system. Simulation results are presented to validate the components models and the chosen control scheme.