【作者】 许辉；

【导师】 杨晓萍；

【作者基本信息】 西安理工大学 ， 水利水电工程， 2004， 硕士

【摘要】 随着科学技术及社会文明的不断进步和发展，尤其是以信息技术为先导的知识经济的到来，人们越来越多的使用了对电能质量十分敏感的以计算机和微处理机等为核心的自动化生产设备，这就对电能质量提出了更高的要求。然而，随着电网中冲击性、非线性负荷的不断增加，导致电网电压波形发生畸变、波动、闪变和三相不平衡等电能质量问题却越来越严重。因此，对电能质量问题的改善就显得尤为迫切了。 用户电力技术(Custom Power)是基于现代电力电子技术、旨在改善配电网电能质量和提高供电可靠性的前沿课题。其目的是通过系统的方法，将配电系统改造成无电压波动、无不对称以及无谐波的实时控制的柔性化配电网，以满足电力负荷对供电质量和供电可靠性日益提高的需求。动态电压恢复器(Dynamic Voltage Restorer—DVR)是Custom Power家族的一个重要成员，它可以补偿电压的跌落、突升以及谐波，具有高性价比的优点。因此，对DVR进行研究是十分有必要的。 本文首先对DVR的主电路进行了讨论，再此基础上，对DVR的电压检测方法、电压补偿策略以及控制策略进行了研究。DVR的检测方法与谐波、无功电流的检测不同，不但需要检测出除基波分量之外的总畸变分量，还要检测出基波分量与基波基准值之差。本文对基于瞬时无功功率理论的谐波电压瞬时检测方法进行了改进，提出了适应DVR的电压检测方法。在分析了各种补偿策略的基础上提出优化补偿策略，这种方法兼顾了DVR的电压补偿能力和能量补偿能力两个方面，因此更具有实用价值。针对传统开环控制方式的不足，分析了电压环控制策略。 仿真结果表明，本文采用的电压补偿策略、检测方法和控制策略是正确、有效的。随着技术的成熟和成本的降低，DVR必将在配电网中得到广泛的应用。更多还原

【Abstract】 With the development of science and technology and social civilization, especially the coming of knowledge economy precursed by information technology, more and more automation production assemblies which have the computers and microprocessors as the core and are sensitive to power quality are used, higher requirements are put forward to power quality. Moreover, owing to rapid use of large numbers of nonlinear or impactive loads in power system, many power quality problems will be caused, such as voltage sag, swell, unsymmetry, flicker, fluctuation, harmonic and so on. Therefore, the betterment of power quality is utterly urgent.The application of Custom Power is quite promising in distributed systems. It becomes one of the research emphases in recent years. Its objective is to reconstruct distribution system into real time controlled and flexible one, which has no flickers, no asymmetry, and no harmonics. Dynamic Voltage Restorer (DVR) is an important member of Custom Power family. It can compensate voltage harmonic, fliker, sag, swell, unbalance, and has the advantage of high performance/price, so it is necessary to investigate the theory and operation of DVR.Firstly the main circuit of DVR is discussed in this paper, on the basis of which voltage detecting method, voltage compensation strategy and controlmode are studiedBased on the analysis of several compensation strategies, optimal compensation strategy is proposed which considers both voltage compensation capacity and energy compensation capacity of DVR, so it is more practical. The detecting method of DVR is different from harmonic and reactive current detecting methods. It need detect not only total harmonic distortion but also the difference between fundamental wave component and reference value. An DVR voltage detecting method is brought forward, which is improved from harmonic voltage instantaneous detecting method based on general instantaneous reactive power theory. Arming at the shortages of traditional control mode, voltage loop control strategy is analyzedThe simulation conclusion indicates that voltage compensation strategy, detecting method and control mode are correct and effective. Along with the mature of the technology and the decrease of the cost, DVR will have broad application in distribution system.更多还原