title: Fiber Bragg grating temperature sensors in a 6.5-MW generator exciter bridge and the development and simulation of its thermal model.
abstract: This work reports the thermal modeling and characterization of a thyristor. The thyristor is used in a 6.5-MW generator excitation bridge. Temperature measurements are performed using fiber Bragg grating (FBG) sensors. These sensors have the benefits of being totally passive and immune to electromagnetic interference and also multiplexed in a single fiber. The thyristor thermal model consists of a second order equivalent electric circuit, and its power losses lead to an increase in temperature, while the losses are calculated on the basis of the excitation current in the generator. Six multiplexed FBGs are used to measure temperature and are embedded to avoid the effect of the strain sensitivity. The presented results show a relationship between field current and temperature oscillation and prove that this current can be used to determine the thermal model of a thyristor. The thermal model simulation presents an error of 1.5 °C, while the FBG used allows for the determination of the thermal behavior and the field current dependence. Since the temperature is a function of the field current, the corresponding simulation can be used to estimate the temperature in the thyristors.
authors.affiliation: Graduate Program in Electrical and Computer Engineering, Federal University of Technology-Paraná, Curitiba-PR 80230-901, Brazil. kleitonsousa@utfpr.edu.br.
authors.forename: Kleiton
authors.initials: K
authors.lastname: de Morais Sousa
authors.affiliation: University of Applied Science, Munich 80335, Germany. werner.probst@bayern-mail.de.
authors.forename: Werner
authors.initials: W
authors.lastname: Probst
authors.affiliation: Electrical Engineering Graduate Program, Federal University of Technology-Paraná, Pato Branco-PR 85503-390, Brazil. fernando.bortolotti@copel.com.
authors.forename: Fernando
authors.initials: F
authors.lastname: Bortolotti
authors.affiliation: Graduate Program in Electrical and Computer Engineering, Federal University of Technology-Paraná, Curitiba-PR 80230-901, Brazil. cmartelli@utfpr.edu.br.
authors.forename: Cicero
authors.initials: C
authors.lastname: Martelli
authors.affiliation: Graduate Program in Electrical and Computer Engineering, Federal University of Technology-Paraná, Curitiba-PR 80230-901, Brazil. jeanccs@utfpr.edu.br.
authors.forename: Jean Carlos Cardozo
authors.initials: JC
authors.lastname: da Silva