Active Power Control for Grid-Connected Photovoltaic System: A Review

The penetration of grid-connected photovoltaic systems (PVSs) shows a trend of ever-increasing, which yields potential risk in power system. To further enhance the integration penetration, the power from PVSs is required to obtained advanced functionalities, such as peak power limitation, voltage fluctuation elimination and frequency regulation capacity. Hence, kinds of functional ancillary services are developed and standardized in grid codes. Meanwhile, the approaches should be cost-effective, which is benefit to the competitive strength of solar (a) energy. In this paper, a compressive review on modified MPPT-based active power controls for grid-connected PVSs is giving out. The basic concept of these controls is to move the operation point away from maximum power point, which is suitable to exist PVSs and no extra requirements are needed. Besides, detailed analysis of some key issues in control designs, such as the determination of available power and the selection of operation point, are carried out in this paper.