A Lab Setup Illustrating Thyristor-Assisted Under-Load Tap Changers

This paper proposes a simple enough yet challenging lab setup illustrating the application of power electronics to power system devices through a thyristor-assisted under-load tap changer. After a preliminary analysis of the special switching concepts involved in this application, a thorough description of the main steps comprising the proposed experiment is carried out. This lab setup has been included in the electrical engineering curriculum (major in power engineering) of most senior undergraduate students (fifth year in several European countries).