非对称混合多电平逆变器功率均衡方法  

Power Balance Strategy for Asymmetric and Hybrid Multilevel Inverter

作　　者：张云[1] 孙力[2] 王要强[2] 

机构地区：[1]天津大学电气与自动化工程学院,天津市南开区300072 [2]哈尔滨工业大学电气工程及自动化学院,黑龙江省哈尔滨市150001

出　　处：《中国电机工程学报》2010年第18期15-20,共6页Proceedings of the CSEE

摘　　要：针对非对称混合多电平逆变器特点,提出一种锯齿载波交错相移混合调制方法,分析各功率单元输出电压的基波幅值关于调制度的非线性曲线,重构功率均衡约束曲线。以功率均衡约束曲线,推导出H桥单元导通角关于调制度的约束方程,在高低调制度阶段分别对功率单元进行动态的功率均衡调节。仿真对比数据表明,功率均衡后,消除了低调制度阶段功率单元输出分配的极端现象,在输出线电压质量不变的情况下实现了功率均衡。高调制阶段,在输出线电压总谐波畸变率(total harmonic distortion,THD)略有增加的情况下,解决了功率单元负荷不均问题。实验结果验证了功率均衡方法的可行性与有效性。According to the characteristics of the asymmetric and hybrid multilevel inverter,the phase-shifted staggered saw-tooth carrier hybrid modulation method was proposed.The nonlinear curves of the basic fundamental amplitude corresponding to modulation depth from each power cell were analyzed.Then the restricted track of power balance was established.In addition,the switching angle function corresponding to modulation depth for H bridge cell is deduced with it.Therefore the power balance control can be carried out dynamically with both lower and higher modulation depths respectively.Contrastive simulation results make it clear that it eliminates the distributing extreme phenomena of the power cells outputs after power balance control with lower modulation depth,while power balance is achieved with the changeless quality of the output voltages.With higher modulation depth,the unbalanced charge of power cells is solved in the case of increasing total harmonic distortion（THD） of the output voltage just a little.Finally,the experimental results verify the feasibility and validity of the proposed power balance control.

关 键 词：电力电子 多电平逆变器 调制方法 脉宽调制 功率均衡 非对称混合 

分 类 号：TM46[电气工程—电器]