基于MMC-UPFC对称分量控制的输电线路三相不平衡治理  

Suppression of Three-phase Unbalanced Current of Transmission Lines Based on Symmetrical Component Control of MMC-UPFC

作　　者：满九方 郝全睿[1] 高厚磊[1] 李正[1] 王淑颖 

机构地区：[1]电网智能化调度与控制教育部重点实验室(山东大学),山东省济南市250061 [2]国网山东省电力公司济南供电公司,山东省济南市250012

出　　处：《中国电机工程学报》2017年第24期7143-7153,共11页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51507093);中国博士后基金项目(2015M572029)~~

摘　　要：该文采用基于模块化多电平换流器(modular multilevel converter,MMC)的统一潮流控制器(unified power flow controller,UPFC),提出一种通过在线路中串联负序电压来治理输电线路三相不平衡的通用控制策略,建立MMCUPFC在正、负序同步旋转坐标系下的双环控制器,分析不同变压器接线方式对于零序分量的抑制效果,并设计相应的环流抑制控制器。定量分析MMC-UPFC在常规运行方式和三相不平衡治理时的潮流运行范围,给出其运行范围准确的数学解析式,并采用逐点扫描法进行验证。最后,在PSCAD/EMTDC中搭建MMC-UPFC及相关控制系统模型,进行不同情况下三相不平衡治理的仿真。仿真结果表明:所提出的控制方法具有良好的控制通用性和鲁棒性,能够有效地治理多种原因造成的线路三相不平衡。In this paper, a general control strategy based on modular multilevel converter（MMC）-unified power flow controller（UPFC） was proposed to control the three-phase unbalance of transmission line by series negative sequence voltage in the line. The dual-loop controller of MMC-UPFC in positive and negative synchronous rotating reference frame was established and the effect of different transformer connection modes on zero sequence components was analyzed. In addition, the corresponding circulating current suppressing controller was designed. The operation range of MMC-UPFC was analyzed quantitatively under the balanced conditions and three-phase unbalanced suppression control, and the mathematic analysis formula of the operation range of MMC-UPFC was given. The accuracy of the formula was verified against the point-by-point scanning method. MMCUPFC and related control system model were built in PSCAD/EMTDC, and simulation of three-phase unbalanced control was carried out in different situations. The simulation results show that the control method proposed in this paper has good control universality and robustness, and can effectively deal with the three-phase unbalance caused by various reasons.

关 键 词：统一潮流控制器 模块化多电平换流器 三相不平衡 环流抑制控制器 潮流调节 

分 类 号：TM72[电气工程—电力系统及自动化]