Comparison of Nonlinear Excitation Controllers for Power System Stabilization

Abstract

The aim of this paper is to construct nonlinear synchronous generator excitation controllers and compare their effects on the dynamic performance of a single machine-connected-to-aninfinite-bus system. Two of these controllers are derived from the universal sliding mode control structure, while the third one is a modified form of the finite-time state homogeneity controller. The performance of the system under the action of these controllers is investigated through the application of a three-phase symmetrical fault at the infinite bus. Simulation results presented for various fault durations of 9, 14.5, 14.7, and 15 cycles show that all the controllers (which can be practically realized using fast power semiconductor devices in a staticexciter structure) perform well, with the homogeneity-based controller exhibiting the best robustness ability.

Control strategies in enhanced stand-alone mini-grid operations for the NESI–an overview

“…No inner-loop current regulation is required in both DTC and DPC, which makes it less sensitive to system parameter variations, i.e., they are more robust against system parameter mismatch. Classical DTC and DPC are achieved by non-linear hysteresis controllers (Maes and Melkebeek, 2000;Buja and Kazmierkowski, 2004;Poddar and Ranganathan, 2004) with an asymmetrical switching frequency dependent on the load, but interest in symmetrical switching in DTC and DPC have yielded promising results via feedback linearization techniques and proportional plus integral (PI) controllers (Nik Idris and Mohamed Yatim, 2004;Zhi andXu, 2007, Balogun et al, 2013;Awelewa et al, 2020, Awelewa et al, 2016Abdulkareem et al, 2022). A DTC for a DFIG that is applicable to both wind and small hydroenergy conversion systems is illustrated in Figure 9 with symmetrical switching frequency.…”

“…Moreover, with the proliferation of renewable energy sources (RESs) in the energy mix because of near zero carbon footprints, micro-/mini-grids are becoming more competitive and attractive for investors than legacy grids. The reason for such competitiveness is partly because most RESs are usually integrated at the distribution buses (Arfeen et al, 2019), which will not require huge capital investment on equipment and manpower because of lower voltage levels of integration (Lovejoy, 1992;Bidram and Davoudi, 2012;Hazelton et al, 2014;Mipoung et al, 2014;Dang et al, 2015;Singh et al, 2015;Unamuno and Barrena, 2015;Nasirian et al, 2016;Dehkordi et al, 2017b;Arcos-Aviles et al, 2018;Castilla et al, 2019;Flowers, 1997;Lasseter, 2002;Lasseter and Paigi, 2004;Lasseter, 2011;Olivares et al, 2014;Tahir and Mazumder, 2015;Chen et al, 2016;Fioriti et al, 2017;Li et al, 2017;Moayedi and Davoudi, 2017;Chen et al, 2018;Sen and Kumar, 2018;Xu et al, 2019;Jumani et al, 2020;Mujtaba et al, 2020;Shrestha et al, 2020;Abdulkareem et al, 2022;Anand et al, 2013;Awelewa et al, 2016;Awelewa et al, 2020;Buja and Kazmierkowski, 2004;Concari et al, 2016;De Carne et al, 2015;De Carne et al, 2018;…”

State of charge estimation based on a modified extended Kalman filter

“…where Ak, Bk, and Ck are Jacobean matrices derived from first order Taylor series approximation [28] of, V0…”