Systems and methods for synchronising islanded power grids with a main power grid

A system for synchronising an islanded power grid with a main power grid, the system comprising:

• at least one first phasor measurement unit (PMU) that in use, collects first phasor data associated with the main power grid, wherein the first phasor data comprises time-stamped voltage phasors and frequency values at an electrical node within main power grid close to a connection point;
• a plurality of second PMUs that in use, collect second phasor data associated with the islanded power grid, wherein the second phasor data comprises time-stamped voltage phasors and frequency values at a plurality of electric nodes which at least include a plurality of energy sources in the islanded power grid;
• a main controller of the islanded power grid that is communicably coupled to the at least one first PMU and at least one of the plurality of second PMUs, the main controller being configured to:
• receive the first phasor data and the second phasor data;
• receive a command from a device associated with an operator of the system;
• and then
• execute the frequency correction process iteratively using the first phasor data and the second phasor data, to match a frequency of the islanded power grid to a frequency of the main power grid;
• execute a phase and voltage magnitude correction process iteratively using the first phasor data and the second phasor data, to match a phase and voltage magnitude of the islanded power grid at the connection point to a phase and voltage magnitude of the main power grid;
• and
• send an activation signal to at least an electrical element arranged at the connection point, causing the electrical element to establish an electrical connection between the islanded power grid and the main power grid upon receiving the activation signal.