Computer-aided methods of determining thyristor thermal transients

An accurate tracing of the thyristor thermal response for determination of the rating of the thyristor and prediction of its performance is investigated. Several alternatives to thyristors for thermal modeling and analysis by using an electrical circuit analog are offered. These methods are adaptable to numerical solutions and well suited to the use of the digital computer. The thermal analysis of thyristors was performed for the 1000 MVA converter system at the Princeton Plasma Physics Laboratory. Transient thermal impedance curves for individual thyristors in a given cooling arrangement were known from measurements and from manufacturer´s data. The analysis pertains to almost any loading case, and the results are obtained in a numerical or a graphic format