Transient Stability of Power Generating Stations synchronously connected to Low Inertia Electrical Power systems
Citation:ZARIFAKIS, MARIOS, Transient Stability of Power Generating Stations synchronously connected to Low Inertia Electrical Power systems, Trinity College Dublin.School of Engineering.ELECTRONIC AND ELECTRICAL ENGINEERING, 2018
PhD Thesis, hardbound final, double sided, 20180214v01.pdf (ethesis) 11.64Mb
The ever-present requirement to decarbonize energy generation, consequently the impetus to increase energy levels from sustainable sources means that wind turbines and solar photovoltaic installations have become major contributors to the energy pool. All studies of isolated grids (e.g. Ireland) indicate that increase of these sources weakens the ability of the frequency in the transmission and distribution system to remain stable after transient disturbances because of the consequent decreased inertia in the electrical power system. The behaviour of the grid and in particular the grid frequency is manifested as an increase of the Rate of Change of Frequency (ROCOF) which may give rise to oscillations in the entire transmission system. Therefore, the goal of maximizing the renewable energy level on a transmission system when the grid inertia is low without compromising the safety and integrity of the existing generator assets should be attained. Hence a rigorous approach permitting quantitavie understanding of low inertia grids based on dynamical models is developed. These are torsional nonlinear oscillators which may oscillate about a temporary equilibrium orientation and so may describe the response of the grid and the grid connected assets to transient frequency changes. They are inspired by previous applications in statistical mechanics, and comprise two bodies rotating about a fixed axis connected by a nonlinear spring subject to external torques. This stimulus causes a change in the angular velocity of both masses resulting in a oscillatory motion of the entire coupled system. The models are verified by comparison with actual measurements in existing power generating stations so highlighting limitations to the operational range of synchronous generators. Thus one may identify the minimum system inertia and so the limit to the quantity of grid connected non-synchronous generation. The governing nonlinear equations of motion are solved by adapting techniques similar to those developed for stochastic differential equations (v. The Langevin Equation, 4th edition, W.T. Coffey and Yu.P. Kalmykov, World Scientific, 2017). The results allow simple analytic description of systems with high wind electricity generation or other asynchronous renewable energy sources and so support the overall goal of decarbonizing electricity generation.
Electricity Supply Board
Author: ZARIFAKIS, MARIOS
Qualification name:Doctor of Philosophy (Ph.D.)
Publisher:Trinity College Dublin. School of Engineering. Discipline of Electronic & Elect. Engineering
Type of material:Thesis
Availability:Full text available
Showing items related by title, author, creator and subject.
Organic farming and landscape structure: Effects on insect-pollinated plant diversity in intensively managed grasslands POWER, EILEEN; STOUT, JANE; KELLY, DANIEL; KELLY, DANIEL LUCIUS; POWER, EILEEN; STOUT, JANE CATHERINE (2012)12 Hide Figures Abstract Introduction Methods Results Discussion Supporting Information Acknowledgments Author Contributions References Reader Comments (0) ...
The potential for indirect effects between co-flowering plants via shared pollinators depends on resource abundance, accessibility and relatedness STOUT, JANE; POWER, EILEEN; POWER, EILEEN; STOUT, JANE CATHERINE (2014)Co-flowering plant species commonly share flower visitors, and thus have the potential to influence each other's pollination. In this study we analysed 750 quantitative plant–pollinator networks from 28 studies representing ...
POWER, EILEEN; POWER, EILEEN; STOUT, JANE (2011)1. Pollination interactions comprise a network of connections between ?owers and insect visitors. They are crucial for reproductive success in many angiosperms but are threatened by intensive agricultural practices. ...