模块化多电平换流器测量失准的感知及定位  

Sense and Location Method of Measurement Failure in MMC

作　　者：金阳忻 徐习东[2] JIN Yangxin;XU Xidong(Marketing Service Center,State Grid Zhejiang Electric Power Co.,Ltd.,Hangzhou 311121,China;Department of Electrical Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]国网浙江省电力有限公司营销服务中心,杭州311121 [2]浙江大学电气工程学院,杭州310027

出　　处：《高电压技术》2023年第4期1495-1506,共12页High Voltage Engineering

基　　金：国家自然科学基金(51877188)。

摘　　要：由于子模块众多,直流电网模块化多电平换流器(modular multilevel converter,MMC)的测量系统复杂度较高,易出现个别传感器测量失准的问题。首先,基于MMC的控制模型,对电压、电流传感器测量失准造成的影响进行了定量分析,研究了MMC中电压及电流间存在的冗余关系,并利用离散积分首次推导了计及测量不确定度的子模块电容电压迭代估计值,该算法的收敛性可由不动点原理加以证明。然后,基于残差范数提出针对各种测量失准工况的感知判据,并给出其灵敏度。最后,通过PSCAD/EMTDC时域仿真进行验证,仿真结果表明:测量失准对MMC各层控制的效果均有不同程度的影响;该文提出的失准判据可在1s内精准感知及定位若干个失准的电压及电流传感器,有效降低其对系统安全稳定运行的影响。Due to the existence of a quantity of sub-modulars,the measurement system of modular multilevel converter(MMC)in DC grid possesses high complexity,thus the problem of sensor measurement failure may easily occur.First,the measurement failure effect of voltage and current sensors were analyzed quantitatively based on MMC mathematic module.The redundancy among the voltage and current in MMC were analyzed.With measurement uncertainty being taken into account,iterative submodule(SM)capacity voltage estimates were deduced by discrete integral,whose convergence is able to be proved by the fixed point principle.Furthermore,aimed at various measurement failure conditions,the sense criteria and their sensitivity were put forward based on residual norm.Finally,PSCAD/EMTDC time domain simulation was carried out.The results show that the MMC control effect of each layer can be affected by measurement failure to different extents,meanwhile,the proposed criteria are able to sense and locate several failed voltage and current sensors precisely in 1 s,which benefits the system safety and stability.

关 键 词：模块化多电平换流器 测量失准 离散积分 不动点原理 感知判据 灵敏度 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM46