Novel structure for unbalance, reactive power and harmonic compensation based on VFF-RLS and SOGI-FLL in three phase four wire power system

CC‐ROGI‐FLL based control for grid‐tied photovoltaic system at abnormal grid conditions

“…I^L q = I^L α2 + I^L β1 (19) I^L α2 is also an estimated in-phase fundamental current component, which is obtained by shifting I^L α1 by 90° and I^L β2 is the estimated quadrature fundamental current component, which leads I^L β1 by 90°.…”

“…The low pass filters are used in d-q theory based control algorithm, consequently, the response of system becomes sluggish and has high settling time under the unbalanced loads as reported in the literature [17]. There are various phase-locked loop (PLL)-and frequency-locked loop (FLL)-based advanced control algorithms such as synchronous reference frame (SRF)-based PLL [18], second-order generalised integrator (SOGI)-based FLL [19], dual SOGI (DSOGI)-based PLL [20], which are used to achieve the good power quality with grid-integrated system. However, these controls have few demerits such as SRF-PLL has sluggish response and high complexity and SOGI-FLL has deteriorated response under higher order harmonics [21].…”

Current control based on limit cycle stability for photovoltaic arrays

“…One very popular non-PLL synchronisation scheme is the second-order generalised integrator-FLL, which has been combined with wavelet transform and fuzzy logic controller. They provide good synchronisation and acceptable harmonic content rejection [6,[26][27][28][29][30]. However, they have the cost of solving a high number of control states.…”

Simple and efficient control of DSTATCOM in three‐phase four‐wire polluted grid system using MCCF‐SOGI based controller

“…The authors of [26][27][28] present the use of SOGI for grid connected photovoltaic systems. The authors of [29,30] present that SOGI is implemented in TPFW systems.…”