【作者】 许晓艳；

【导师】 王伟胜； 赵海翔；

【作者基本信息】 中国电力科学研究院 ， 电力系统及其自动化， 2009， 硕士

【摘要】 随着化石性燃料的日益消耗,能源危机和环境污染已经成为当今世界所面临的严峻问题,开发和利用可再生能源成为必然的发展趋势。在诸多的可再生能源利用中,太阳能光伏发电已经成为世界各国竞相发展的可再生能源发电方式之一,而并网型光伏电站也越来越受到重视并得到较快的开发和利用。本论文在综述国内外光伏发电发展概况、运行特性研究现状以及太阳能光伏发电系统工作原理的基础上,对大型并网光伏电站模型进行研究,并在Matlab/Simulink和电力系统分析软件DIgSILENT/PowerFactory中实现,为研究和解决大型光伏电站并网运行的工程问题奠定了基础。本论文包括以下主要内容：(1)并网型光伏电站模型及其控制系统研究。重点对光伏电池模型、逆变器模型及其并网控制策略进行研究,建立仿真平台；对不同并网控制策略下光伏电站的并网特性及短路电流特性进行仿真分析。(2)研究大型光伏电站对系统无功电压的影响。以实际工程为例,研究两种控制策略下光伏电站对电网无功电压的影响,提出利用逆变器自身调节能力以及在光伏电站进行集中补偿的改善措施。(3)研究光伏电站对孤立电网暂态稳定性的影响,并提出提高系统稳定性的技术措施。经过算例验证,表明频率控制环节可以有效抑制负荷变动和电网发生短路故障造成的频率波动,逆变器保护装置可保证光伏电站在故障期间不脱网,维持系统频率稳定,光伏电站电压源并网有利于电动机起动时的电网电压恢复。(4)研究光伏电站接入配电网对短路电流的影响,进而分析光伏电站接入后对配电网保护以及自动重合闸的影响及措施。更多还原

【Abstract】 Energy crisis and environmental pollution have been extraordinary severe with the increasing consumption of fossil fuel. It is highly necessary to exploit and utilize renewable energy to decrease such crisis. In the utilization of various renewable energy, photovoltaic (PV) has been one of the widely used and increasingly developing meods to generate power all over the world. Moreover, for this power generation method, grid-integrated PV stations are highly focused and rapidly extended.On the basis of summarizing the PV development worldwide, research works on operation characteristics, and the basic principle of PV generation system, the purpose of this dissertation is to model large grid-integrated PV stations in Matlab/Simulink and a integrated power system simulation software DIgSILENT/PowerFactory, providing a platform to study and analyze the problems after large PV stations are integrated in the existing power system. The main works of this dissertation are as follows:(1) Study the modeling methods and the control methods for large grid-integrated PV stations. The focus for this study is the mathematic description of PV cells, inverter and the control of inverter in consideration of the existing power system. Simulation will be done based on the proposed model and control method. Characteristics and short current for the grid-integrated PV stations will be thus achieved.(2) Study the effect on reactive power and voltage for integrated large PV stations. Taking a practical PV station as an example, the effect of the PV station on reactive power and voltage is thoroughly investigated. In order to improve the static voltage stability, two solutions are suggested, i.e., installing reactive power compensation devices and controlling the output power of the inverters in PV stations.(3) Analyze PV station’s effect on the transient stability of the small grid under different fault form, and put forward technique measures to improve the transient stability. By calculating a case, it is indicated that frequency controller can restrain frequency fluctuation after fault, and protection device of inverter can make PV stations connected to grid during fault, thereby, keep frequency stable, voltage source control mode can make voltage stable when motor starts.(4) Study PV station’s impact on protection of urban power network. Study the impact on short current of system and then analyze the impact on protection of system and automatic reclosure.更多还原