Metodologia para modelagem de transformadores de potencial indutivo e capacitivos para estudos de transitórios em altas frequências

• Ano de defesa: 2015
• Autor(a) principal: Camargo, Matheus de Castro
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; BR; Engenharia Elétrica; UFSM; Programa de Pós-Graduação em Engenharia Elétrica
• Palavras-chave em Português: Transformador de potencial indutivo; Transformador de potencial capacitivo; Transitórios eletromagnéticos; Modelagem para altas frequências; Inductive voltage transformer; Capacitive voltage trasnformer; Eletromagnetic transients; High-frequency modeling; CNPQ::ENGENHARIAS::ENGENHARIA ELETRICA
• Link de acesso: http://repositorio.ufsm.br/handle/1/8577

This dissertation proposes a modeling methodology for Inductive and Capacitive Voltage Transformers (IVT and CVT) for high-frequency electrical transients analysis, up to 3 MHz. The model construction starts from the VT s sweep frequency test, carried out by a commercial Sweep Frequency Response Analyzer (SFRA) with special connections, in order to obtain its short-circuit Admittance Matrix. The SFRA is designed for another purpose, to detect displacement of windings or fault in the magnetic core of power transformers based on voltage transfer analysis. Therefore, due to this fact, the measured data needs to be corrected and recalculated, through and external routine, to adequately represent the proper and mutual admittance values of the Matrix. After its correction, the Admittance Matrix serves as input data to the Matrix Fitting method, a frequency-response approximation tool by means of modified rational functions, which is part of the Vector Fitting (VF) routine, freely available for non-commercial purposes in MATLAB®. The results are an approximated rational function, in state-space or pole-residue model, and a RLC equivalent network proper to be used in electromagnetic transients analysis software, such as the Alternative Transients Program (ATP). The models validation is accomplished based on the comparison between the transient responses of the created model, through simulation in ATP/EMTP, and the IVTs and CVTs laboratory tests when both are submitted to a step function excitation.