US 12,270,715 B2
Method for estimating parameters of a junction of a power semi-conductor element and power unit
Nicolas Degrenne, Rennes (FR); Nicolas Voyer, Rennes (FR); and Stefan Mollov, Rennes (FR)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Appl. No. 17/781,220
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
PCT Filed Oct. 23, 2020, PCT No. PCT/JP2020/040733
§ 371(c)(1), (2) Date May 31, 2022,
PCT Pub. No. WO2021/124707, PCT Pub. Date Jun. 24, 2021.
Claims priority of application No. 19306719 (EP), filed on Dec. 20, 2019.
Prior Publication US 2023/0003586 A1, Jan. 5, 2023
Int. Cl. G01K 7/01 (2006.01); G01K 7/42 (2006.01); G01K 15/00 (2006.01); G01R 31/26 (2020.01)
CPC G01K 7/01 (2013.01) [G01K 7/427 (2013.01); G01K 15/005 (2013.01); G01R 31/2607 (2013.01); G01R 31/2619 (2013.01); G01R 31/2628 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A Method for estimating parameters of a junction of a power semi-conductor element comprising:
detecting at least one stable on-line operating condition through measurements of Von, Ion, Tc on said power semi-conductor element where Ion is a current for which on-state voltage Von of said power semi-conductor element is temperature sensitive and Tc is the temperature of the casing of said power semi-conductor element;
measuring and storing at least one set of parameters Von, Ion, Tc of said at least one stable operating condition;
minimizing error between a junction temperature estimation Tj of an electrical model Tj=F(Von, Ion, θelec) comprising a first set of unknown parameters θelec and another junction temperature estimation Tjmod of a thermal model Tjmod=G (Ion, Tc, θ mod) comprising a second set of unknown parameters θ mod and obtaining at least one set of parameters θelec and at least one set of parameters θ mod providing minimization of said error;
providing the calculated value of Tj with at least one of the calculated sets of parameters θelec and/or θ mod, and the measured Von, Ion, Tc;
storing the at least one set of parameters θelec and/or θ mod and/or Tj; and
estimating the parameters of the junction by comparing the stored at least one set of parameters θelec and/or θ mod and/or Tj, with the at least one set of parameters at another moment in time to provide maintenance warnings.