Device and method for measuring fretting displacement in power cycle of press-pack IGBT

An in-situ measurement method for a fretting displacement in a power cycling experiment of a press-pack insulated gate bipolar transistor (IGBT) module,

• wherein the in-situ measurement method for the fretting displacement in the power cycling experiment of the press-pack IGBT module is measured by a device for measuring a fretting displacement in a power cycling of a press-pack IGBT,
• the device for measuring the fretting displacement in the power cycling of the press-pack IGBT comprises:
• a bracket;
• slide bars slidably mounted on the bracket and at least four slide bars are arranged along a circumferential direction of the bracket;
• sensors respectively slidably installed on the bracket and the slide bars;
• and a power cycling experiment device arranged inside the bracket;
• the power cycling experiment device comprises an IGBT chip layer, wherein the IGBT chip layer transversely corresponds to the sensors on the slide bars;
• at least two sensors are arranged on the bracket, and longitudinally correspond to the sensors on adjacent slide bars, and moving directions of the slide bars and the sensors are perpendicular to each other;
• the sensors adopt picometer laser displacement sensors;
• there are six picometer laser displacement sensors, wherein four, a first picometer laser displacement sensor, a second picometer laser displacement sensor, a third picometer laser displacement sensor and a fourth picometer laser displacement sensor , are used to measure the fretting displacements in an X direction and a Y direction;
• the first and third picometer laser displacement sensors are installed on sliders in the X direction, and the second and fourth picometer laser displacement sensors are installed on the sliders in the Y direction;
• the remaining two picometer laser displacement sensors are used to measure displacement zero positions in the X and Y directions, and are a fifth picometer laser displacement sensor and a sixth picometer laser displacement sensor respectively, and are installed on the sliders on chutes of a bottom frame;
• the first and third picometer laser displacement sensors have the same coordinates in the Y direction and a Z direction, the second and fourth picometer laser displacement sensors have the same coordinates in the X direction and the Z direction, the first and fifth picometer laser displacement sensors have the same coordinates in the Y direction, and the second and sixth picometer laser displacement sensors have the same coordinates in the X direction;
• and
• the in-situ measurement method for the fretting displacement in the power cycling experiment of the press-pack IGBT module comprises:
• S1, controlling the sensors to positions of the chip layer where the fretting displacements need to be measured by motors, and fixing the picometer laser displacement sensors by electromagnetic switches;
• S2, since reflected lights of the sensors change when the chip layer frets, transmitting electrical signals to a computer through an acquisition card after a photoelectric conversion;
• and
• S3, calculating a thermal expansion rate, a micro-sliding amount and a micro-sliding angle through the electrical signals received by the six sensors.