Non-PLL for fast grid-inverter synchronization in microgrids applications

In this paper, a fast-synchronization between grid and inverter based on virtual synchronous converter (VSCon) technique is achieved in single-phase inverter. Consequently, this technique is designed and simulated in Matlab/Simulink platform to perceive the significances during variation of grid load parameters. The VSCon is implemented for inverter output control that has a behavior of grid voltage and frequency synchronization using droop control mechanism. This technique has been tested in inverter-microgrid connection with several loads connected. In case of 0.1 Hz grid frequency changes in grid test, it takes nearly 230ms to synchronize between inverter and grid frequency even with loads connected to the test system. Hence, this proposed technique can be implemented in microgrids with several distributed generation sources without using the PLL for fast synchronization between grid-inverters.