Switching-Cycle-Based Startup for Grid-tied Inverters

This paper presents a novel switching cycle-based startup approach that eliminates the need for voltage sensors and phase-locked loops. The proposed method surpasses the bandwidth limitations inherent in traditional PLL-based synchronization techniques and attains grid synchronization of the inverter within two switching cycles. Despite the absence of voltage sensors and PLLs, this synchronization is achieved without inrush currents. Furthermore, the startup method does not necessitate the addition of any hardware or an increase in software complexity. Simulation and experimental results are presented to verify the effectiveness of the proposed method.