| Resumo: | A wider adoption of distributed generation sources and an increased interconnection of networks tend to increase the complexity of electric power grids, thus causing a surge in failures, especially short-circuits. The conventional solution against short-circuit currents, for example, the construction of new substations, splitting of busbars, even updating the technology of the existing current limiters may prove either economically or technically unfeasible. Fault current limiters, mainly the superconducting fault current limiters, have already demonstrated their viability in electric power grids. Fault current limiter devices at normal operation are invisible to the grid, acting almost instantly upon a fault, returning to their normal state upon its correction. To disseminate these technologies, the development of straightforward design tools is required. These tools must consider the properties of the available constitutive elements of the devices. Behind these design tools, the integrity of the fault current limiter should be assured during its operation. Problems regarding the electrodynamic forces developed under short-circuit events must be properly characterized because they can damage windings, causing device breakage and affecting the power grid. In this thesis, a design methodology that intends to model and optimise saturated cores superconducting fault current limiters is presented. This methodology considers the characteristics of each constitutive element of the limiter while addressing utility requirements and power grid characteristics. Genetic algorithms are used both to optimise the constitutive elements of the limiter and its performance in the power grid. In order to validate the present methodology, a three-phase superconducting fault current limiter is designed/optimised, built and tested. The electrodynamic forces analysis developed in superconducting tapes of an inductive transformer type superconducting fault current limiter, under short-circuit conditions is performed.
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