IGCT的原理性电学模型与动态特性仿真

Principle-electrics Model of IGCT and Dynamic Characteristic Simulation

集成门极换向晶闸管(IGCT)因具有开关速度快、损耗低、容量大、导通管压降低等优越性能而正逐渐广泛地应用于中压大功率领域,但国内外仿真软件中尚无IGCT的器件仿真模型。为此根据IGCT的结构特点、工作原理、额定参数以及外总电学特性,应用两个Hu-Ki模型并联的优化模型及ORCAD建立了IGCT的原理性电学模型,给出了模型的电路图及元件参数,并应用该模型进行了IGCT的动态特性仿真与分析,给出了开通、关断电压和电流波形,关断功率脉冲波形,门极关断电压和电流波形。仿真结果显示仿真的IGCT器件关断时间2μs,关断能量约0.1J,关断时门极反向电流峰值25A,表现出明显的反向抽取作用,与实测波形保持了很好的一致性。该模型意义明确、描述准确、结构简单、仿真速度较快,且有一定的通用性,可用于IGCT器件与简单系统的仿真研究,为IGCT的选择应用、器件匹配与保护电路的设计提供研究手段与设计参考。

As one kind of power electronics elements with four-layer semiconductor and three PN junctions, the Integrated gate eommutated thyristor （IGCT） can be simplified to double-transistor equivalent circuit. The turn-on process of IGCT is similar to GTO, but its turn-off process is different from GTO because of the reverse drawing out action of gate pole during turning-off. In this paper, according to the conformation and principle stated above and extra electric characteristic of IGCT, the principle-electrics model of IGCT was investigated using ORCAD based on the two parallel Hu-Ki models. The schematics of the model and the parameters were presented in detail. Subsequently, the dynamic characteristics of IGCT was simulated using the principle-electrics model of IGCT, and the simulation results, including turn-on voltage, turn-on current, turn-off voltage, turn-off current, turn-off energy pulse, turn-off gate pole voltage and turn-off gate pole current, were presented respectively. The turn-off time of the IGCT simulated in this paper is 2 μs, the turn-off energy is 0.1 J, and the peak value of turn-off gate pole current is 25 A which represents markedly the reverse drawing out action. Additionally, the simulation results are consistent with the test waveforms provided by the ABB company. In conclusion, the principle-electrics model established in this paper has clear physical meaning, simple structure and wide universality, it can be used not only for simulation study of IGCT, but also for choice and application of IGCT, design for auxiliary or protect circuit. However, compared with physical model, the model proposed in this paper can not describe the physical process inside but merely depicts the extra electric characteristic of IGCT.