High Speed Thermal Imaging applied to a Long Pulse Resonant Converter Modulator for Power device Reliability Assessment

This paper considers the design of a modulator supply for RF tube applications. The supply is based on direct modulation of a series resonant parallel loaded power supply. The main aim of this work is to monitor semiconductor losses of the IGBT modules through calorimetry and the device temperature using high speed thermal imaging, during the pulse. The paper provides an overview of the technology and design used on the test rig prototype under study. The final experimental rig layout designed for internal device temperature and loss measurement will be presented. The overall goal of the work is to identify the limitations and reliability of the modulator technology proposed.