基于DMWPWM的三电平NPC变流器闭环控制策略研究  

Research on Closed-loop Control Strategy for Three-level Neutral Point Clamped Converter Based on DMWPWM

作　　者：张辉[1,2] 邓洋 李宁[1] ZHANG Hui;DENG Yang;LI Ning(School of Automation and Information Engineering,Xi’an University of Technology,Xi’an 710048,Shaanxi,China;State Key Laboratory of Safety Control and Simulation of Power System and Power Generation Equipment,Tsinghua University,Beijing 100084,China)

机构地区：[1]西安理工大学自动化与信息工程学院,陕西西安710048 [2]清华大学电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《电气传动》2018年第11期39-42,共4页Electric Drive

基　　金：国家自然科学基金项目(51507140/51277150/51307140);陕西省教育厅自然科学专项基金(15JK1508)

摘　　要：双调制波载波调制策略(DMWPWM)可实现三电平中点钳位(NPC)变流器在全调制度、全功率因数范围无直流电容电压低频波动。对比3类双调制波载波调制策略的直流电压利用率、器件开关损耗和输出电流谐波畸变率(THD),得到最优双调制波载波调制策略,但其本质为开环控制,难以抑制非调制因素引起的直流电容电压不平衡。应用一种基于双调制波载波调制的直流电容电压闭环控制策略,实现中点电位平衡。仿真结果验证了理论分析的可行性与有效性。Double modulation wave carrier-based PWM(DMWPWM)strategy can realize the neutral point voltage control under the entire modulation index and full power factor for three-level neutral point clamped(NPC)converter.In the aspects of DC voltage utilization,switching loss of the device and total harmonic distortion(THD),the three DMWPWM strategies were compared with each other to obtain the optimum DMWPWM strategy.But essential of the strategy was an open-loop strategy,non-modulated factor could not be inhibited to achieve neutral-point balance.Then,a neutral point voltage closed-loop control strategy based on double modulation wave carrier-based PWM was applied to achieve the neutral-point balance.The correctness of theoretical analysis is validated by results from simulation.

关 键 词：三电平中点钳位变流器 双调制波载波调制 闭环控制 中点电位平衡 

分 类 号：TM464[电气工程—电器]