非对称运行状态下换流器改进开关函数模型  

Improved Switching Function Model of Converter Suitable for Asymmetric Operating State

作　　者：贠飞龙 刘崇茹 田鹏飞 李越 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206

出　　处：《电网技术》2016年第5期1301-1307,共7页Power System Technology

基　　金：教育部新世纪优秀人才支持计划项目(NCET-12-0846);高等学校学科创新引智计划("111"计划)(B08013);国网科技部重点科技项目(适应智能化发展需求的电网安全和充裕控制技术研究与应用)~~

摘　　要：传统的换流器开关函数模型应用于非对称运行状态分析时,精度显著降低。详细分析了三相非对称运行状态下换流器的换相过程,并着重考虑了直流侧2次谐波电流对换相持续时间的影响,提出了考虑2次谐波电流影响的换相角计算方法。基于分析建立了考虑阀导通偏移和换相角不等的换流器改进开关函数模型,并通过忽略非必要次谐波简化了模型的计算过程。在Matlab中编程实现了提出的开关函数模型,并采用PSCAD中搭建的Cigre-Benchmark直流标准模型的仿真结果进行检验。分别在逆变侧和整流侧设置换流母线三相不对称,通过对比直流侧直流电压、换流母线三相注入电流及注入功率,验证了提出模型的有效性。Accuracy of traditional switching function model of converter is significantly reduced in asymmetric operation mode.Commutation process in asymmetric operation mode is analyzed,considering impact of the 2^（nd） harmonic in DC side during commutation.A calculation method for commutation overlap angle is proposed considering the 2（nd） harmonic component.An improved switching function model of converter is established,where valve conduction effects and unbalanced commutation overlap angles are taken into account.Calculation process is simplified by ignoring non-essential harmonics.Comparison of simulation results in PSCAD and calculation in MATLAB on DC voltages,AC currents and injected active and reactive powers shows that the proposed model is effective in asymmetric operation mode.

关 键 词：非对称运行 换相过程 2次谐波电流 换相角计算 换流器 开关函数模型 

分 类 号：TM46[电气工程—电器]