基于免疫算法的逆变器无死区控制优化  

Optimal Dead-Time Elimination for Voltage Source Inverters Based on Immune Algorithm

作　　者：袁佳歆[1] 费雯丽[1] 魏亮亮[1] 潘建兵[1] 陈柏超[1] 田翠华[1] 

机构地区：[1]武汉大学电气工程学院,武汉430072

出　　处：《电工技术学报》2013年第9期247-254,共8页Transactions of China Electrotechnical Society

基　　金：国家重点基础研究发展规划(2009CB724506);国家自然科学基金(50807041)资助项目

摘　　要：在电压源逆变器控制中为避免同一相桥臂上下两个功率器件发生直通,通常需要设置死区,但这易导致逆变器的输出电压和电流发生畸变。本文在分析各种减少或消除死区影响方法的基础上,针对单相全桥逆变器提出一种新的三电平死区控制策略。在不需要精确的电流极性检测条件下,该方法可以实现在电流零点附近以及各区域之间无缝过渡的无死区控制。并借助于免疫算法对满足死区消除方法的脉宽调制(PWM)控制序列进行优化,提高逆变器输出波形质量。本文对新控制策略进行仿真研究和搭建了基于数字信号处理器(DSP)控制器的试验平台进行小容量模拟实验。实验和仿真结果证明该算法所产生的无死区最优PWM控制序列与常规控制策略相比不仅能有效地消除死区影响,还能明显减小逆变器输出波形的总谐波畸变率(THD)。A dead time should be considered in a PWM gate signal in order to avoid the short-circuit of inverter legs. Such a dead time causes some problems such as output voltage and current waveforms distortion. Based on the analysis of the effect of eliminating the dead-time, this paper proposes a novel dead time elimination method for single phase full bridge inverter which employs the three-level PWM control strategy. The presented method can eliminate the dead time clearly and implement a smooth transition through the whole cycle without a precise current polarity detection circuit. In addition, by using the IA as the search method for finding the optimal control sequences accord with the no dead time rules, the algorithm can optimize the quality of an output current waveform. Furthermore, an experimental platform based on DSP and FPGA is built. The simulation and experimental results verify the best dead time elimination control sequences generated by IA compared with the existing conventional control strategies, not only effectively and safely eliminate the effect of dead time, but also significantly reduce the THD of the output waveform.

关 键 词：免疫算法 无死区 最优PWM控制 总谐波畸变率 

分 类 号：TM344.1[电气工程—电机]