Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title A Method to Improve the Performance of Phase-Locked Loop (PLL) for a Single-Phase Inverter Under the Non-Sinusoidal Grid Voltage Conditions
Authors Reyyan Ahmad Khan ; Woojin Choi
Page pp.231-239
ISSN 1229-2214
Keywords SRF-PLL(Synchronous Frame PLL) ; PLL(Phase Lock Loop) ; Synchronization ; Single phase grid-tie inverter
Abstract The phase-locked loop (PLL) is widely used in grid-tie inverter applications to achieve a synchronization between the inverter and the grid. However, its performance deteriorates when the grid voltage is not purely sinusoidal due to the harmonics and the frequency deviation. Therefore, a high-performance PLL must be designed for single-phase inverter applications to guarantee the quality of the inverter output. This paper proposes a simple method that can improve the performance of the PLL for the single-phase inverter under a non-sinusoidal grid voltage condition. The proposed PLL can accurately estimate the fundamental frequency and theta component of the grid voltage even in the presence of harmonic components. In addition, its transient response is fast enough to track a grid voltage within two cycles of the fundamental frequency. The effectiveness of the proposed PLL is confirmed through the PSIM simulation and experiments.