Active power regulation in low voltage grid-tied inverters for rooftop solar PV systems: Progress and future directions

The current global expansion of rooftop solar photovoltaic systems, exceeding 130 GW in the residential sector, is primarily driven by worldwide energy demands and government initiatives. Typically, grid-tied inverters used in rooftop systems are integrated into the secondary distribution network of the power system. The intermittent nature of solar energy leads to variations in solar photovoltaic power generation, resulting in potential fluctuations in grid frequency and voltage. Under specific conditions such as peak power generation periods and light-load scenarios, rooftop systems can cause grid voltage variations (Deviations from IEEE 929, IEEE1547 Rule21) in low-voltage grid environments. This review article aims to assist emerging researchers and industry professionals in understanding the current trends in Active Power Regulation (APR) for Low Voltage Grid-Tied Inverters (LV-GTIs). The review highlights the need for APR, the selection of appropriate configurations and topologies, and emphasizes the key technical requirements for LV-GTIs to ensure accuracy, high dynamic response, and stability at reduced power levels. This review is the first of its kind, addressing the challenges and potential solutions related to APR in LV-GTIs for rooftop solar photovoltaic applications.