A Modified SOGI-PLL with Adjustable Refiltering for Improved Stability and Reduced Response Time

The controls of most power electronic inverters connected to an electrical system (EPS) rely on the precise determination voltage magnitude, frequency, and phase angle at point common coupling. One widely used approaches for measuring these quantities is phase-locked loop (PLL); however, precision this measurement affected during transients in EPS a function type event architecture PLL. PLLs based second-order generalized integrator (SOGI) are converter synchronization, offering adaptive or fixed-parameter prefilter with low-pass band-pass characteristics. This article proposes variant SOGI-PLL that offers improved stability faster response time. accomplished by decoupling effect SOGI’s gains adding feedback. modification carried out state space model SOGI. Manipulating attenuation moves poles SOGI improve stability. performance proposed PLL verified validated under processor-in-the-loop (PIL) approach.