A robust Phase-Locked-Loop approach for the generation system with power flow control

The main contribution of this paper is to describe a robust Phase-Locked-Loop approach for three phase generation system with power flow control. This method, which is used to synchronize the inverter and the network voltages, is based on a comparison between the grid and the inverter angular positions, and correction of modulator period. The Solution presented in this paper is applied to the three level three phases NPC inverter, which is connected to the grid, and using an open loop circuit for its power flow control. The limitation of the proposed method is presented, as well as the closed loop control strategy is discussed in this work, and visualizes fulfilling results. Extensive simulation and experimental results are presented to verify the effectiveness of the robust Phase-Locked-Loop approach and its application in three phase system, including the ability to operate with unity power factor and high efficiency.