IGBT Junction Temperature Estimation via Gate Voltage Plateau Sensing

• Published in: IEEE transactions on industry applications Vol. 54; no. 5; pp. 4752 - 4763
• Main Authors: van der Broeck, Christoph H., Gospodinov, Alexander, De Doncker, Rik W.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.09.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Circuits; Detection; Electric potential; Gate voltage plateau; Insulated gate bipolar transistors; insulated-gate bipolar transistor (IGBT); junction temperature estimation; Junctions; Logic gates; Phase current; Semiconductor devices; Sensitivity; Sensitivity analysis; Temperature measurement; temperature sensitive electrical parameters (TSEPs); Temperature sensors; Threshold voltage
• ISSN: 0093-9994; 1939-9367
• DOI: 10.1109/TIA.2018.2836362

A method for in situ high-bandwidth junction temperature estimation of insulated-gate bipolar transistors is introduced in this paper. The method is based on the acquisition of the gate voltage plateau during turn- on . It can be related to the junction temperature at any known device current, that can be effectively approximated using existing phase current measurements. This allows fast overtemperature protection of the power device or even active thermal cycle reduction via thermal control. This paper discusses, first, the physical mechanisms leading to the temperature sensitivity of the gate voltage plateau. Second, a rigorous sensitivity analysis of the gate voltage plateau is conducted. It allows to determine the maximal estimation error and provides information about the suitability of this method for various devices and applications. Finally, a sensing circuitry is presented, which allows accurate gate voltage plateau sensing every switching period as well as an easy integration into the gate driver. The performance of the proposed method is experimentally demonstrated with the sensing circuitry on a double pulse test bench over a wide operation range.