5SHX1060H0002 IGCT可控硅主板

5SHX1060H0002 通流能力，在DCB关断过程中，电流从机械开关支路转移至电力电子支路，开关管导通线路短路电流约3~5ms后关断。关断时的温度过高可能导致关断失败，而强开关管的通流能力在通流期间的温度上升较小，关断大电流的可靠性较高。IGCT具有较强的电导调制效应，通态压降远低于IGBT，且不会出现IGBT的退闸现象，在通流期间的温度上升远低于IGBT，因此具有更高的通流能力。

5SHX1060H0002 The through-current capability, during DCB shutdown, the current is transferred from the mechanical switching branch to the power electronic branch, and the switching tube conducts the line short-circuit current for about 3~5ms before shutting down. The high temperature during shutdown may lead to shutdown failure, while the through-current capability of strong switching tubes has a smaller temperature rise during the through-current period, and the reliability of shutting down large currents is higher.IGCT has a stronger conductance modulation effect, the on-state voltage drop is much lower than that of the IGBT, and the phenomenon of back-off of the IGBT does not occur, the temperature rise during the through-current period is much lower than that of the IGBT, and thus it has a much higher through-current capability.

5SHX1060H0002 换流能力对于自然换流型DCB，换流速度取决于机械开关触头间弧压与电力电子支路通态压降的差值。由于IGCT的导通压降终端，以9kA、125℃为例，相近电压电流等级的单体IGCT和IGBT的导通压降分别为3.2V和6V [ 25 ]，从而IGCT-DCB的换流速度更快。另外，对于相同电弧电压，在满足换流的情况下，相同电压等级的IGCT可串联数量较大的IGBT，自然换流混合式IGCT-DCB适用的电压等级较高。

5SHX1060H0002 Commutation Capability For a natural commutation type DCB, the commutation speed depends on the difference between the arc voltage between the mechanical switch contacts and the on-state voltage drop of the power electronic branch. Since the on-state voltage drop of IGCT is terminal, for example, for 9kA and 125°C, the on-state voltage drops of single IGCT and IGBT of similar voltage and current ratings are 3.2V and 6V, respectively [ 25 ], resulting in faster commutation speed of IGCT-DCB. In addition, for the same arc voltage, a larger number of IGBTs can be connected in series with IGCTs of the same voltage rating to satisfy the commutation, so that the natural commutation hybrid IGCT-DCB is applicable to a higher voltage rating.

5SHX1060H0002 过流工况，当电流转移至电子支路后，若在机械开关触头间隙达到绝缘强度之前，短路电流已上升至接近最大关断电流极限，为保证器件不损坏，IGBT必须迅速关断并建立电压，造成机械开关过压击穿而导致DCB关断失败。而IGCT则选择维持导通，当线路电流下降至可关断范围后再进行关断。因此IGCT-DCB处于过流工况下的关断具有较大的优势。

5SHX1060H0002 Overcurrent condition, when the current is transferred to the electronic branch, if the short-circuit current has risen to close to the maximum shutdown current limit before the mechanical switch contact gap reaches insulation strength, in order to ensure that the device is not damaged, the IGBT must quickly shut down and build up the voltage, resulting in the mechanical switch over-voltage breakdown and leading to the failure of DCB shutdown. The IGCT, on the other hand, chooses to maintain conduction and turn off when the line current drops to the turn-off range. Therefore, IGCT-DCB shutdown under overcurrent conditions has a greater advantage.