抽水蓄能机组背靠背变流器中点电压平衡控制  

Neutral-point Voltage Balance Control of Back-to-back Converter in Variable Speed Pumped Storage Units

作　　者：孙静 邵宜祥[1,2] 周百灵 朱菲菲[2] SUN Jing;SHAO Yixiang;ZHOU Bailing;ZHU Feifei(State Grid Electric Power Research Institute,Nanjing 211106,Jiangsu,China;NARI Technology Company Limited,Nanjing 211106,Jiangsu,China)

机构地区：[1]国网电力科学研究院,江苏南京211106 [2]国电南瑞科技股份有限公司,江苏南京211106

出　　处：《电气传动》2018年第10期64-69,共6页Electric Drive

摘　　要：研究了三电平二极管中点钳位变换器在可变速抽水蓄能机组中的应用。首先,建立机组的交流励磁系统。然后,重点研究三电平变换器的中点电位平衡控制,分析中点电位偏移的原因,在开环合成虚拟矢量的基础上,引入中点电位偏移值反馈,提出闭环合成虚拟矢量的控制方法,对于机组中的背靠背变流器,提出根据变换器交流电流有效值之比协调控制中点电位。最后,通过在Matlab中搭建仿真模型验证所提出的控制系统具有良好的控制性能。The application of three-level neutral-point-clamped converters in variable speed pumped storage units(VSPSU)was focused on.First,the AC excitation system of the VSPSU was presented.Then,the emphasis was on the neutral-point voltage balance control of three-level converter.The causes for the deviation of neutral-point voltage were analyzed,and on the basis of open-loop virtual space vector synthesis,a closed-loop virtual space vector synthesis algorithm was proposed by taking the deviation of neutral-point voltage as the feedback.For the back-to-back converter in the VSPSU,a coordinated control of its neutral-point voltage was proposed according to the effective values of its two sides alternating current.For verification,the simulation system of VSPSU with the proposed control system was built in Matlab/Simulink,and the simulation results prove that the proposed control system takes on good performance.

关 键 词：三电平变换器 中点电位平衡 虚拟空间矢量合成 

分 类 号：TM921[电气工程—电力电子与电力传动]