Single-phase string inverter systems convert the DC power generated by the photovoltaic (PV) panel arrays into the AC power fed into a 120 V / 220 V single-phase grid connection.
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.
A micro inverter operating in grid-connected mode should satisfy the grid connection standards in terms of power quality, THD ratios, islanding detection, grid interfacing limits for voltage and frequency, and grounding.
There are numerous standards defining the interconnection and disconnection of single-phase inverters to utility grid available. The solar inverters are one of the most extensively researched topics in emerging power electronics due to their variety in circuit and control architectures.
What is a grid-connected inverter?
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.
Therefore, grid side controller of solar inverter should meet grid interconnection requirements, provide secure grounding, and power decoupling features. The inverters improved for operating in single-phase grids should comply with grid requirements described by several international and regional standards.
The user must not touch the board at any point during operation or immediately after operating, as high temperatures may be present. Do not leave the design powered when unattended. Grid connected inverters (GCI) are commonly used in applications such as photovoltaic inverters to generate a regulated AC current to feed into the grid.