| Abstract |
This paper proposes a novel modified third-order generalized integrator phase-locked loop (TOGI-PLL) for balanced, unbalanced, and distorted grid conditions. This technique also eliminates the error factors that cause in experimental such as DC-offset and removing the second-order oscillation noise by adding the low-pass filter when generating the estimated filtered frequency. A step-by-step controller design procedure, system stability analysis, and comparison with the traditional second-order generalized integrator (SOGI), dual second-order generalized integrator (DSOGI), and decoupled double synchronous reference frame PLL (DDSRF-PLL) are carried out. The proposed PLL approach is simulated and experimentally implemented on a three-phase 7.5kW grid-connected inverter system. |
