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Reduced-order modelling and simulation of integrated AC-DC systems using GAM-type dynamic phasor solution approach Liang, Xing

Abstract

Modelling and transient simulation of electric power systems and their components is enabling field of research much needed for planning, design, and operation of present and future evolving electrical grids and systems. The line-commutated-rectifiers (LCRs) are commonly used in integrated AC-DC energy conversion systems, where they are also known as the source of harmonics. Recently, a full-order parametric dynamic phasor (PDP) modelling methodology has been proposed in the literature for efficient transient simulation of the LCR systems including harmonics. Although this modelling approach is able to capture any desired number of harmonics, this increased accuracy also comes at an additional computational cost. The main objective of this thesis is to improve the numerical efficiency of transient simulation of the LCR systems with harmonics using the parametric dynamic phasor (PDP) modelling methodology. In this thesis, a reduced-order PDP model is proposed to reduce the computational cost and enable faster simulations. The fundamental DPs are represented by differential equations, while high-order DPs are represented by algebraic equations. Moreover, the harmonic ripples that may exist in the DC subsystem have also been incorporated to increase the modelling fidelity of the new approach. The superior performance of the new technique is validated on several examples of integrated AC/DC power systems (including three-phase transformer and synchronous machine). Rigorous case studies demonstrate that the reduced-order PDP model of integrated AC/DC systems is capable of accurately tracking the steady-state and transient responses, while providing higher numerical efficiency compared to the conventional detailed model and the prior established full-order PDP models.

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Attribution-NonCommercial-NoDerivatives 4.0 International