In microgrid systems, the role of ATS (Automatic Transfer Switch) is to realize the automatic switching between two AC power sources (such as grid power and microgrid off-grid power).
It works with STS (Static Transfer Switch) to ensure the continuity of power supply: when the main power source (e.g., grid power) fails or needs to switch to off-grid mode, ATS can automatically switch the power supply to the backup power source (e.g., microgrid internal power supply), avoiding power interruption to critical loads.
In the microgrid system, ATS is one of the core internal components, cooperating with PCS, EMS and other equipment to support the flexible switching between grid-connected and off-grid modes of the microgrid. It normally used to connect Grid Power and Diesel Generator, and switch between this two power source.