Dual-inverter for grid-connected photovoltaic system: Modeling and sliding mode control

A fast and robust control strategy for a multilevel inverter in grid-connected photovoltaic system is presented. The multilevel inverter is based on a dual two-level inverter topology. There are two isolated PV generators that feeding each bridge inverter. The output of each inverter is connected to a three-phase transformer. The active and reactive powers flowing into the grid are controlled by a sliding mode algorithm. An alfa–beta space vector modulator is also used. The inverters DC voltages are also controller by a sliding mode controller. In this way, a fast and robust system controller is obtained. Several test results are presented in order to verify the effectiveness of the proposed system controller.

► A multilevel inverter based on a dual two-level inverter topology for grid connected photovoltaic system. ► There are two isolated PV generators that feeding each bridge inverter. ► A model of the multilevel system is presented. ► The active and reactive powers flowing into the grid are controlled by a sliding mode algorithm.