GRID INTEGRATION OF VOLTAGE SOURCE CONVERTER USING POWER SYNCHRONIZATION CONTROL

Abstract

Renewable Energy Sources (RES) are integrated with electric power systems around the world at an accelerated pace. Due to their intermittent nature, integrating RES into the power grid is a challenging task. Because of their good controllability and superior performance in weak AC grids, the three phase Voltage Source Converters (VSCs) are generally used for this purpose. The grid connected converter has to correctly detect the grid voltage signal during voltage distortion and unbalance condition. In this research work, a control method using power synchronization for grid integration of VSC is developed and simulated. In this control technique, the electricity fed to AC grid from VSC is controlled using the internal synchronization mechanism as like in conventional synchronous machine. Utilizing this type of control, the instability of VSC affected by a standard Phase Locked Loop during weak grid condition can be avoided. Moreover, a VSC terminal could support a weak AC system with strong voltage, just similar to an ordinary synchronous machine organizer. Simulations are done in Matlab/Simulink to validate the system performance of grid attached VSC with the Power Synchronization Control.