IGBT功率器件工作中存在的问题及解决方法

Problems occurred in IGBT and their resolvents

绝缘栅双极型晶体管IGBT(InsulatedGateBipolarTransistor)因其开关速度快、工作频率高、控制方便等优点得到广泛应用,但随着电力电子技术的高频、大功率化发展,开关工作时会造成较高损耗和严重的电磁干扰,甚至元件本身也会因过压、过流问题造成损坏。从IGBT的内部结构特点出发,讨论了IGBT工作中上述问题存在的原因,整理了目前国内外常用的一些处理措施,包括软开关技术、吸收电路技术以及研制新的开关元件等。软开关通过控制电压、电流状态,使其在开关过程中保持不变,抑制di/dt,du/dt;吸收电路是吸收开关过程中di/dt,du/dt产生的多余能量,然后反馈至其他地方。而采用新的开关元件集成门极换流晶闸管IGCT(IntegratedGateCommutatedThyristor),从开关本身出发解决问题是个有潜力的方案。

IGBT(Insulated Gate Bipolar Transistor) is widely used because of its merits of high swi-tching speed,high frequency and easy control. But along with power electronics technology deve-lopment for higher frequency and capacity,the switcher brings high losses and severe EMI,and the over-voltage or over-current results in component damage. The causes are discussed from the inner structure of IGBT and the typical countermeasures are summarized,including soft-switching,snubber circuit and new switching component. The soft-switching holds the states of voltage and current during switching period to restrain the d i / d t and d u / d t;the snubber circuit absorbs the extra energy produced by d i / d t and d u / d t and feeds back to another region. Application of new switching component IGCT (Integrated Gate Commutated Thyristor) is a challenging scheme.