Low voltage ride-through operation of single-phase PV systems

Due to the continuously declining price of photovoltaic (PV) modules, the penetration of grid-connected PV systems is becoming higher and higher. In modern power grids, the power generation from PV systems takes a significant part of the total power production. In this case, the PV systems should be more active in grid regulation. Practically, the grid voltage may experience various disturbances, e.g., voltage sags and frequency variations. In this chapter, the requirements on PV systems in response to voltage faults are reviewed. Advanced control strategies for single-phase PV systems (single-stage and double-stage configurations) are presented with simulations. At the end of this chapter, the reactive power injection issue is discussed, and three strategies for single-phase systems are presented. This will enable the full capability of the PV systems in the low voltage ride-through operation.