摘要
模块化多电平电压源换流器高压直流输电(modular multilevel converter high voltage direct current,MMC-HVDC)技术是一种新型的电压源换流器直流输电技术。计及交流系统与换流站交换功率的数学关系,应用图解法分析了交流电网强度对MMC-HVDC系统稳态特性的影响,同时分析了接入强、弱交流电网的直流系统在不同控制方式下设定值改变时的暂态特性。结果表明功率圆的大小及其相对位置可以直观地反映交流电网的强弱,以及控制方式对MMC-HVDC系统运行特性的影响。最后PSCAD电磁暂态仿真验证了上述结论的正确性。
High voltage DC (HVDC) transmission based on modular multilevel converter (MMC) is a new type of HVDC transmission technology based on voltage source converter (VSC). Taking mathematical relationship of the exchanged power between the AC system and the converter station into account, the influence of AC system strength on steady state characteristics of MMC-HVDC is analyzed by graphic method, meanwhile the transient characteristics of HVDC system connected to strong/weak AC system are analyzed while the setting values of the different converter control modes are changed. Analysis results show that the strength of AC system as well as the influence of converter control modes on operating characteristics of MMC-HVDC system can be reflected by the size of power circle and its relative position visually. The correctness of above-mentioned conclusion is verified by the results of the simulation based on PSCAD electromagnetic transient model.
出处
《电网技术》
EI
CSCD
北大核心
2011年第2期17-24,共8页
Power System Technology
基金
国家自然科学基金项目(50777058)~~
关键词
高压直流输电
模块化多电平换流器
功率圆
运行特性
交流电网强度
HVDC power transmission
modularmultilevel converter (MMC)
power circle
operationalcharacteristics
AC system strength