Grid-connected fully automatic solar inverter

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 control design of this type of inverter may be challenging as several algorithms are required to run the inverter. This reference design uses the C2000 microcontroller (MCU) family of devices to implement control of a grid connected inverter with output current control.

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.

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.

In the grid-connected inverter, the associated well-known variations can be classified in the unknown changing loads, distribution network uncertainties, and variations on the demanded reactive and active powers of the connected grid.