A voltage-fed single-stage multi-input inverter for hybrid wind/photovoltaic power generation system.

A voltage-fed single-stage multi-input inverter for hybrid wind/photovoltaic power generation system is proposed, and its circuit topology, control strategy, and derivation of multiple duty ratios are studied in detail. Also, the methods to avoid turn-off voltage spike of selection switches and magnetic saturation of line-frequency (LF) transformer are fully investigated. The maximum power point tracking outer loop/grid-connected current (GCC) inner-loop control strategy decomposes the GCC according to the maximum power provided by each input source, to ensure the power distribution of each source and the direct control of GCC. By adjusting the drive signals of selection switches, the feedback path for inductor current is ensured and the voltage spike is intrinsically eliminated. The introduction of the DC bias correction loop for GCC restrains the magnetic saturation of the LF transformer. Simulation and experimental results of the designed 3 kW laboratory prototype verify the feasibility and validity of the theoretical analysis. [ABSTRACT FROM AUTHOR]