Recent advances in synchronization techniques for grid-tied PV system: A review

The contribution of solar photovoltaic (PV) in the electrical power sector is increasing expeditiously. Recent interest in the integration of solar PV into the grid raises concerns about the synchronization technique. Continuous research has successfully replaced the small stand-alone system with a grid-tied PV system. A grid-tied PV system is popular due to the abundance of solar light and advanced power electronics techniques. This paper helps to provide a basic conceptual framework to develop a superior grid-tied system. Synchronization is a crucial problem in grid-tied inverters operation and control research indicates that frequency, phase, and amplitude of voltage are the most crucial parameters that need to be measured and controlled for grid-tied application. This paper presents the state of the art of various synchronization methods for both single-phase and three-phase units. A phase-locked loop (PLL) is a popular grid synchronization approach, which needs to sustain power system oscillations as its vulnerability influences the produced reference signal. Traditional PLL catches the frequency and phase through feedback loop-filter (LF) to improve steady-state capability during adverse grid conditions. The review paper focuses on the power stages architecture of PV fed grid synchronization along with a comparison of various PLL techniques based on their merits and demerits. This paper will be the one-stop reference for the researchers in the area of PV-fed grid.