摘要
基于全桥MMC的柔性直流输电系统,能迅速隔离直流线路故障,得到了广泛的应用。损耗是衡量换流阀的重要指标,文中对基于全桥MMC换流阀的损耗进行分析,运用分段解析计算的方法给出具体的计算表达式。首先,将MMC换流阀的总损耗分为通态损耗和开关损耗两部分。然后,根据桥臂电流的方向,桥臂电压与投入子模块个数之间的关系,运用分段解析方法得到MMC换流阀的通态损耗;之后,根据每个子模块投切状态变化对应的能量损耗进行分段解析计算,求得MMC换流阀的开关损耗;将这两部分损耗进行综合,从而得出基于全桥MMC换流阀的总损耗。仿真结果验证了文中所提出的损耗分析方法的准确性。
The full bridge of MMC-HVDC (modular multilevel converter based high voltage direct current systems) can rapidly isolate DC line faults,which is widely used.Losses are an important indicator of converter valves.This paper analyzes the losses of the full bridge and proposes a piecewise analytical formula method for loss calculation of converters.Firstly,the total losses of MMC converter valves are divided into two parts:conduction losses and switching losses.Secondly,according to the direction of the bridge arm current and the relationship between the bridge arm voltage and the numbers of input sub-modules,we can get the conduction losses of the MMC converter by using the piecewise analytical method.Thirdly,according to each sub-module's energy losses in switching state,the specific expression of switching losses can be acquired by a piecewise analytical formula method.The total losses of the full bridge are obtained by the conduction losses adding the switching losses.Simulation results verify the accuracy of the proposed method in this paper.
作者
荣飞
田新华
饶宏
周保荣
黄守道
RONG Fei;TIAN Xinhua;RAO Hong;ZHOU Baorong;HUANG Shoudao(College of Electrieal and Information Engineering,Hunan University,Changsha 410082,China;State Key Laboratory of HVDC,Eleetric Power Researeh Institute,China Southern Power Grid,Guangzhou 510620,China)
出处
《高压电器》
CAS
CSCD
北大核心
2019年第1期1-7,14,共8页
High Voltage Apparatus
基金
国家重点研发计划(2016YFB0901001)~~
关键词
换流阀
柔性直流输电
通态损耗
开关损耗
分段解析方法
converter valve
flexible DC transmission
conduction losses
switching losses
piecewise analytical method
