基于指数恢复模型的晶闸管阻容吸收参数设计

A Parameter Design of RC Snubber for Thyristors Based on Exponential Recovery Model

首先介绍了一种基于指数函数反向恢复特性的晶闸管Matlab仿真模型;然后利用该指数恢复模型建立了晶闸管RC吸收回路的仿真电路,通过大量不同RC参数组合情况下的仿真数据,得出了过电压倍数、电阻损耗与RC参数之间的关系曲线;并进一步分析这些曲线的变化规律,总结出了吸收电阻和吸收电容的参数设计原则。最后结合工程实例,给出了一个晶闸管阻容吸收参数设计的具体步骤。现场测试结果表明,该方法非常实用、有效。

First of all,a thyristor Matlab model with exponential reverse recovery current is introduced. Then a RC snubber branch of thyristor simulation circuit is built by the model. Through much simulation data of various R,C parameters,many relationship curves about ratio of over-voltage and power loss versus R,C is obtained. After analyzing these curves,the design principles of optimized resistance R and capacitance C are determined. At last,an parameter design of RC snubber for thyristors in a engineering project is presented. In practice,the over-voltage experiment result is fully proved that the approach is very practical and effectual.