【作者】 王鹏；

【导师】 王奔；

【作者基本信息】 西南交通大学 ， 电力系统及其自动化， 2013， 硕士

【摘要】 随着大功率电力电子器件和PWM技术的发展,轻型直流输电(VSC-HVDC)技术越来越受到人们的关注。VSC-HVDC技术具有潮流翻转方便灵活,有功功率和无功功率可快速独立控制和可向无源网络供电等诸多优点,加强其相关课题的研究具有重要的现实意义。本文着重研究在模型不确定、控制器参数摄动和外部干扰情况下,VSC-HVDC系统的鲁棒控制策略。本文在分析了VSC-HVDC系统电压源换流器(VSC)结构图的基础上,考虑到模型参数的不确定性,建立了dq0坐标系下VSC被控对象的不确定模型,利用线性矩阵不等式(Linear Matrix Inequality, LMI)方法对不确定系统设计了状态反馈鲁棒H∞控制器,然后,分别完成了对VSC-HVDC系统整流端和逆变端控制器的设计。在此基础上,考虑到控制器参数发生加性范数有界摄动的情况,利用LMI方法对VSC的不确定系统设计了鲁棒非脆弱H∞控制器,接着分别设计完成了VSC-HVDC系统整流端和逆变端的控制器。最后,通过Matlab仿真实验验证了所设计两种控制器的有效性和优越性。本文还在分析了VSC-HVDC系统结构图的基础上,考虑到实际工程中存在的外部干扰,建立了VSC-HVDC系统在dq0坐标系下强耦合的非线性数学模型。然后,分别针对整流端和逆变端仿射非线性系统,采用精确线性化方法,将非线性系统变换为新坐标系下的线性系统,利用H。控制理论求取了线性系统下的状态反馈控制律,接着反演设计出原VSC-HVDC系统整流端和逆变端的控制器。最后,通过Matlab仿真实验验证所设计控制器能够实现有功功率和无功功率的独立控制,具有较好的动态性能和较强的鲁棒性。更多还原

【Abstract】 With the development of high-power power electronic elements and PWM technique, VSC-HVDC has more and more attention and has been successfully used in actual power system. VSC-HVDC has many advantages, for example, it can reverse the direction power flow flexibly, obtain the individual control of active power and reactive power, supply the power to passive network and etc. It has important practical significance to strengthen research on the subject of VSC-HVDC. The robust control strategies for VSC-HVDC are mainly studied in considering the uncertainty in the model, the controller parameters perturbation and the external interference in this paper.This paper analyzes the block diagram of voltage source converter of VSC-HVDC system firstly, and then establishes the state space equations for the controlled object in the dqO coordinate system in considering model parameters uncertainty. The paper designs state-feedback robust H∞controller for the uncertainty model by applying LMI(Linear Matrix Inequality) technology, and then designs robust H∞controllers for rectifying side and inversion side of the transmission system respectively. On that basis, the author focuses on that the controllers often exist parameters perturbation in the practical engineering application, and then designs robust non-fragile H∞controllers by applying LMI technology for rectifying side and inversion side of the transmission system respectively. At last, the Matlab simulation demonstrates that the proposed controllers poss good robust performance and non-fragile performance.This paper also analyzes the block diagram of VSC-HVDC transmission system, and establishes the nonlinear uncertainty system model of the transmission system in the dqO coordinate system in considering external disturbance. The paper turns the nonlinear model into the linear model in new coordinate system by exact linearization, then gets the control law of the linear model by H∞control theory, and then designs H∞controllers for rectifying side and inversion side of the transmission system respectively. At last, the Matlab simulation demonstrates the proposed controllers poss effective performance and good robust performance.更多还原