虚拟同步控制在MMC-HVDC无缝切换控制的应用  

Application of Virtual Synchronization Control to Seamless Mode Switch Control of MMC-HVDC Systems

作　　者：彭斌[1] 沈征[1] 帅智康[1] 尹新[1] 周猛[1] 

机构地区：[1]湖南大学电气与信息工程学院,长沙410082

出　　处：《电力系统及其自动化学报》2016年第11期88-94,共7页Proceedings of the CSU-EPSA

基　　金：国家自然科学基金资助项目(51377051);整晶圆特大容量IGBT器件研究项目(51277060);智能电网中宽频域谐波及其串并联谐振问题与对策研究项目(51207048)

摘　　要：针对MMC(modular multilevel converter)型VSC-HVDC(voltage source converter-high voltage direct current)在并网运行模式与孤岛运行模式相互切换过程中易于发生切换失败、冲击电流大的难题,将虚拟同步控制运用到MMC的运行模式切换中。在虚拟同步控制和MMC基本原理的基础上,提出基于虚拟同步控制的MMC-HVDC(modular multilevel converter-high voltage direct current)无缝切换控制方法。引入的虚拟同步控制无需采用专门的同步控制电路,并网前可自动与电网同步;并网后能准确跟随电网频率,实现友好并网。当电网出现故障或需要检修时,MMC仍可孤岛运行,从而实现了运行模式的无缝切换。PSCAD/EMTDC平台下的仿真结果验证了所述控制策略的可行性和有效性。Modular multilevel converter （MMC） based voltage source converter high voltage direct current （VSC- HVDC） systems are susceptible to large inrush currents or system failure when switching between the grid-connected and islanded operation modes. This paper introduces a virtual synchronization control to realize a seamless mode switch control method for the MMC to solve this problem. The virtual synchronization control method allows automatic synchro- nization with the grid without requiring any dedicated physical synchronization control units, and it follows the grid frequency accurately after being connected to the grid, realizing a friendly connection. When the grid fails or needs offline maintenance, the MMC can continue to operate in an islanded mode to realize a seamless switch between operation modes. The validity and effectiveness of the proposed control strategy is verified by simulaticns on PSCAD/EMTDC plat- form.

关 键 词：虚拟同步控制 无缝切换 模块化多电平直流输电 并网控制 孤岛运行 

分 类 号：TM464[电气工程—电器]