基于双层模型的可控电流源换流器损耗优化方法

Loss Optimization Method for Controllable Current Source Converter Based on Two-level Model

逆阻型集成门极换流晶闸管是构建可控关断电流源型换流器(current source converter,CSC)的可行器件之一。在换流器运行过程中,损耗的产生使得器件芯片结温上升,从而限制了换流阀的运行能力,因此必须明确并优化CSC中器件结温情况。该文提出了系统性的损耗特性、约束条件,建立了损耗抑制的双层模型,并给出了求解方法。提出了缓冲电路和损耗分析的综合设计方法,对缓冲回路及杂散参数范围进行了研究,对比了优化后的CSC与传统直流和柔性直流换流阀的损耗。结果表明,基于该模型的计算参数,器件损耗为5.7kW,电阻损耗约为1.8kW,器件结温增量为38℃,CSC的损耗与系统占比为0.54%。

The Reverse blocking integrated gate commutated thyristor(RB-IGCT)is the feasible devices for controllable turn-off current source converter.During the operation of the converter,the generation of losses causes the junction temperature of the chip to rise,thereby limiting the operating ability of the converter valve.Therefore,clarifying and optimizing the device's junction temperature in the current source converter(CSC)is necessary.In this paper,the systematic loss characteristics and constraints are proposed,and a two-level model of loss suppression is established,and the solution method is given.According to the results of this model,the comprehensive optimization methods such as snubber circuit design and loss analysis are given,the range of snubber circuit and stray parameters is studied,and the loss of optimized CSC is compared with that of line-commutated converter(LCC)and voltage-source converter(VSC).The results indicate that based on the parameter tuning of the two-level optimization model,the device loss is 5.7kW,the resistance loss is about 1.8kW,and the device junction temperature increment is 38℃.the ratio of CSC loss to system is 0.54%.