Synchronization of a microgrid with main network through static switch based on neural network controller

A microgrid in form of a distributed system must work in both modes of grid connected and islanding. With considering to the islanding mode of a microgrid, the synchronism conditions should be established to connect it back to the main grid. To synchronism this part of the network to the main power system, at first, phase estimation have to be performed by a static switch. The synchronizers those are used for three-phase systems are based on the use of phase locked loop (PLL) in synchronous reference frame. In this paper a static switch is designed which has a new PLL with neural network controller and can correctly diagnosis the phase angle for an unbalance input voltage vector. This type of PLL relative to the initiative and modified ones has more simple structure. Here, in order to verify the effectiveness of the proposed method, simulation is carried out on Davarzan area microgrid in Iran using MATLAB software.