摘要由于日趋严重的环境与资源问题以及风能利用的成本低廉和技术成熟等原因,风力发电成为电力系统中相对增长最快的新能源发电技术,发展风电成为改善电力系统经济运行极为重要的措施。近几年,风力发电机组单机容量和风电场建设规模都日益扩大,但风力的随机性和间歇性会对电力系统稳定运行产生一定的影响,因此对于含有风电场的电力系统,需要建立正确的数学模型并对该系统进行仿真分析。66228
作为分析的基础,本文建立了风速、风电机组和风电场的数学模型。风电机组的数学模型主要包括风轮机模型、传动机构模型和异步发电机模型,仿真分析了风电机组对于风速四种分量的响应。风电场模型研究中,考虑到尾流效应和地理位置等因素,风电场中各台风机位置处的风速并不相同,因此研究了风能分布的 模型和 模型,结果表明了风能分布模型在大规模风电场模型分析中的重要性。
基于上述模型,本文对风电场一无穷大系统进行了简单的仿真分析,主要包括小干扰稳定分析,风电场的并网、负荷扰动以及联络线故障时的暂态分析。
最后,本文研究了双馈电机的数学模型,用电力系统静态分析和暂态仿真分析的方法比较双馈发电机和普通异步发电机的特性,研究表明双馈电机对提高风电场短路容量比和改善功率因数都有显著的作用。
毕业论文关键词:风电场,异步发电机,双馈电机,短路容量比
毕业设计说明书(论文)外文摘要
Title Modeling and simulation of wind farms
Abstract
Because of pressure of evironment protection and energy resources, wind energy is developing fastest among all kinds of renewable resources due to its low cost and technical maturity. Wind generation has been an important measure in improving economical operation of power system. In recent years, capacity of wind generators and the scale of wind farm are becoming larger and larger, but the randomicity and intermittence of wind will produce disturbance on power system. Mathematical model of wind generators and wind farm should be established.
As the basis of the analysis, wind speed, wind generators and wind farm are modeled. Wind generator model includes wind turbine model, transferring structure model and asynchronous generator model. Response of wind generators to four kinds of wind speed is simulated and analyzed. In the course of wind farm modeling, wind distribution Jensen and Lissaman model is established by reason of factor of wind wake effect and geographic location, the results show the important role of wind distribution model on large scale wind farm researching.
A simple wind farm connected to infinite bus is simulated and analyzed, which includes small signal disturbance analysis, transient analysis when wind farm starts to be connected, load fluctuates and fault of line in power system is occurred.
The model of doubly-fed induction mechanism is analyzed. Characteristics generators is established and operation of doubly-fed induction generators and normal asynchronous generators is compared by steady analysis and transient analysis. The results show that doubly-fed induction generators have remarkable role in enhancing wind farm short-circuit capacity ratio and improving power factor.
Keywords wind farm, asynchronous generators, doubly-fed induction generator, short-circuit capacity ratio
目 录
1 引言 1
1.1 选题背景及意义 1
1.2 并网风力发电发展情况 3
1.3 大型并网风电场接入电力系统的主要问题及研究现状 5