|
For Car Power module requirements, Infineon IGBT power by increasing circulation and temperature cycle characteristics, and to increase the structural strength of IGBT, IGBT greatly improved the life expectancy. Hybrid vehicles in the power Semiconductor Module requirements Poor working conditions (high temperature, vibration) IGBT in the inverter, the need for high temperature and mechanical impact, according to a specific vehicle drive conditions, the motor for the hybrid system to provide energy. Depending on vehicle design, the inverter may be placed in the vehicle rear, transmission in or near the internal combustion engine under the hood position, so IGBT module to withstand severe temperature (-40 ~ 150 ) and mechanical conditions (vibration, shock) test. IGBT modules are usually cooled by engine coolant, ambient temperature in the limit up to Ta = 105 , on the power module thermal design power density and a higher demand. Complex driving conditions Motor drag different industrial applications, hybrid vehicles driven more complex conditions, such as the corresponding cities, the need to frequently switch on acceleration, deceleration, cruising the states, so the current through the IGBT, the voltage and the great quantity, but with the repeated cycle of fluctuations in traffic conditions, IGBT modules required current, voltage, reliable operation under the impact cycle. High reliability requirements IGBT power module failure will result in immediate loss of vehicle power, seriously affected the credibility of vehicle manufacturers and user experience. Car manufacturers need to HEV IGBT modules without changing the whole life cycle, the durability of the IGBT put a higher demand (automobile design life of 15 years.) Cost control requirements Mass production of vehicle traction application is different from the train, in the performance of demanding conditions, the method can not increase the cost for reliability, the need to balance cost and performance, the design of the product made a higher demand. Thus, for automotive applications, the constraints required to meet the demanding special IGBT applications. IGBT structure Figure 3 shows the power module with the structure of the substrate. Both sides of the copper with a thin layer of ceramic substrate to be welded on the substrate. IGBT Chip Welded copper layer in the designed. Chip's surface through the binding wire (bondingwire) bonding to the copper layer. Most of the standard modules use this production method. At present 70% to 80% of the power modules are manufactured according to the standard module structure. Commonly used ceramic Al2O3, using copper as the substrate material. IGBT base plate through the thermal grease to install the radiator. Automotive Infineon IGBT reliability improvement IGBT reliability is the biggest challenge used in cars, in addition to voltage, current and other conventional parameters of the design considerations involved in the reliability of IGBT main parameters are: temperature cycles (thermalcycling) and power cycle times (powercycling ), determines the IGBT's life, other parameters such as mechanical reliability characteristics of IGBT also require additional attention. Power cycle Typically, the main inverter design considerations IGBTTjmax (maximum junction temperature) limit, but in the hybrid application, the inverter is less constant conditions, acceleration, cruising, deceleration will bring current , voltage changes, resulting Tj (junction temperature of rapid change) will be greater impact of the life of IGBT, IGBT turn-on current volatility, the binding line will swing along on the binding line and IGBT chips connection reliability has significant influence, repeatedly swing life may lead to depletion of bound line (EOL, End ofLife), such as binding wire and welding IGBT chip off, binding wire breakage, a direct result of IGBT damage. Order to simulate the vehicle running condition, often against HEV accelerating, decelerating, cruising to bring the current impact, Infineon defines a "second stage power cycling test" (powercycling second, current heating, external water cooling), through the accelerated aging test, simulation Electric Impact the reliability of binding wire welding, automotive Infineon IGBT to sustain Tj = 60k, the largest section of temperature 150 , 0.5s <tcycl <5s, 150kc times power cycling without damage. Compared to traditional industrial applications, hybrid vehicle (HEV) in the IGBT poor working conditions, and therefore long-term reliability of the IGBT has put forward higher requirements. Relatively traditional industrial modules have the following major improvements: binding wire material improvement; chip structure strengthened; bind cable loop optimization; optimized welding process. We are high quality suppliers, our products such as investment precision casting Manufacturer , China sand metal casting for oversee buyer. To know more, please visits lost wax casting.
Related Articles -
investment precision casting Manufacturer, China sand metal casting,
|
