Magnetic nano-particle based IGBG junction temperature measurement method

The invention discloses a magnetic nano-particle based IGBG junction temperature measurement method. The method comprises that magnetic nano-particles are arranged in a central area in the back of anIGBT chip casing, and a second-order heat transfer model of an IGBT junction, the IGBT chip casing and the work environment is constructed; a uniform AC excitation magnetic field is constructed, the IGBT chip with the magnetic nano-particles is placed in the magnetic field, and then a first harmonic amplitude of a response signal of the magnetic nano-particle is extracted; the temperature of the back of the IGBT chip casing is calculated according to the first harmonic amplitude; and the IGBT junction temperature is calculated according to the back temperature of the IGBT chip casing, the temperature of the work temperature and the second-order heat transfer model. The magnetic nano-particle approach the IGBT junction to improve the precision of IGBT junction temperature measurement; the temperature sensitive char