现代控制理论论文重庆理工大学.doc

三相三电平逆变器的最优控制 （重庆理工大学，重庆市，400054） 摘要：摘要内容基于近年来三相三电平逆变器在中高压调速领域、交流柔性供电系统的无功补偿中的广泛的应用，本文将针对二极管箝位拓扑型三相三电平逆变器进行研究。我们首先将对三相三电平逆变器进行状态空间的数学建模，并在此基础上对研究对象的稳定性及能控能观性等一系列控制特性进行了计算和研究；之后，本文采用基于人工智能的免疫算法（IA）来计算相关状态矢量的最优作用时间，进一步产生最优的PWM控制序列，来控制开关管的开通和关断，以进一步改善三相三电平逆变器的输出特性。本文给出了免疫算法的具体操作步骤和在逆变器最优控制中的具体实施方法，建立了三相三电平逆变器输出波形的数学模型和免疫算法中的各个评价函数。接着通过编写C程序, 并调用Matlab 进行仿真试验, 实验和仿真结果证明，该算法所产生的最优PWM控制序列与常规空间矢量控制策略相比能有效地减小逆变器输出波形的总谐波畸变率，证明了本算法在逆变器最优控制中应用的可行性和有效性。 关键词：三相三电平逆变器；状态空间；免疫算法；最优空间矢量控制 The optimal control of three-phase three-level inverter (Chongqing University of technology, Chongqing, 400054, China) Abstract：Based on the widely use of three-phase three-level inverter in medium-high voltage ac drive systems and FACTS equipments in recent years, in this paper we will do a research of Diode-clam- ped-topological type three phase three-level inverter. Firstly，wo will build a mathematical modeling on state space of the three-phase three-level inverter,and then, the study of the stability and the properties of controllability and observation can proceed with it. After that, this paper based on artificial intelligence immune algorithm (IA) ,we can calculate the optimal effect time of related state vector, further to produce the best PWM control sequence, to control the electronic switch tube to open or shut off, in order to further improve the output characteristics of three-phase three-level inverter. We also give a immune algorithm concrete operation steps and the specific implementation method of optimal control in the inverter application, a mathematics model of output current waveform and evaluation functions in the immune algorithm are also built.Then by programming C language and call Matlab simulation, it is proved that compared with conventional space vector control strategies ,this algorithm has the best PWM control sequence and minimize the THD of inverter output waveform, confirm the feasibility and availability of this algorithm in the optimal control of the inverte