Photovoltaic power generation and grid-connected inverter

As the key interface between new energy generation and power grids, a PV grid-connected inverter ensures that the power generated by new energy can be injected into the power grid in a stable and safe way, and its power grid adaptability has also received more and more close attention in the field of new energy research.

Grid-interactive solar PV inverters must satisfy the technical requirements of PV energy penetration posed by various country's rules and guidelines. Grid-connected PV systems enable consumers to contribute unused or excess electricity to the utility grid while using less power from the grid.

The different solar PV configurations, international/ national standards and grid codes for grid connected solar PV systems have been highlighted. The state-of-the-art features of multi-functional grid-connected solar PV inverters for increased penetration of solar PV power are examined.

As an important part of power conversion in distributed generation, grid-connected inverters can convert the DC power generated and converted by new energy sources such as solar energy and wind energy into AC power. According to their output characteristics, they are divided into grid-forming inverters and grid-following inverters.

Grid-connected PV inverters have traditionally been thought as active power sources with an emphasis on maximizing power extraction from the PV modules. While maximizing power transfer remains a top priority, utility grid stability is now widely acknowledged to benefit from several auxiliary services that grid-connected PV inverters may offer.

State-of-the-art features of grid-interfaced solar PV DC-AC power inverters Reactive power management to keep the grid voltage steady. By regulating the active power injected into the grid in accordance with the droop characteristic, this control function is intended to maintain a constant grid frequency.