含高渗透率风电的电力系统的电压稳定性研究

发布时间：2018-02-15 11:06

本文关键词： 双馈风机风电渗透率风电场等值静态电压稳定暂态电压稳定　出处：《华北电力大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着环境污染问题的日益严重及传统化石能源的逐渐枯竭,以风电为代表的新能源并网技术在世界各国迅速发展。随着风电渗透率的逐渐增大,风电的出力对电网的影响范围也相应增大。在风电渗透率较大的电网中,风电的并网改变了系统潮流的分布,影响了传输线路上的功率以及系统的惯量,同时由于风电的特殊性,风机特性使得电力系统原有的电压稳定性发生变化。本文主要研究风电渗透率的不断增加的电网的电压稳定性,主要内容包括： 1、推导了双馈异步风力发电机的稳态模型及动态模型,从理论上了解风机在静态与动态方面的特性。介绍了以风速为依据,基于K-means聚类算法的分群方法：稳态时只需要得出一个平均风速,即等值为一台机；而暂态情况下得到多个等值机并通过与详细风场的电压、功率等外特性的仿真对比,证明利用K-means方法等值后的风电场准确率较高。 2、用P-V、U-Q曲线的静态电压稳定分析方法,由于传统的P-V曲线是不能体现风电的波动性,通过计算了不同风电渗透率与2015年海南电网的静态电压稳定极限的关系,建立三维的P-V曲面构成的电压安全运行域来表征含风电系统的安全裕度,并利用这种方法确定该系统允许的最大接入容量；利用灵敏度分析指标,针对强、弱系统,考虑不同运行方式下分析风电渗透不断增加对系统电压稳定性的影响。 3、时域仿真是研究电压稳定问题的有效方法。推导了双馈风机对暂态电压的支撑作用,并在单机无穷大网络上证明分析了双馈风机对系统暂态电压的影响。通过在海南2015年运行网架上接入等值风电场,仿真分析改变风电渗透率对该系统暂态电压稳定的影响,结合风机机端电压表达式研究了风电渗透率、接地电阻、短路点位置,接入形式等因素对系统暂态电压的影响。
[Abstract]:With the increasingly serious problem of environmental pollution and the gradual depletion of traditional fossil energy, the new energy grid technology, represented by wind power, is developing rapidly all over the world. The influence of wind power on the power grid is also increased. In the power grid with high wind power permeability, the distribution of power flow is changed, and the power on transmission lines and the inertia of the system are affected. At the same time, because of the particularity of wind power, the characteristics of fan make the original voltage stability of power system change. This paper mainly studies the voltage stability of the grid with increasing wind power permeability. The main contents are as follows:. 1. The steady state model and dynamic model of doubly-fed asynchronous wind turbine are derived, the characteristics of fan in static and dynamic aspects are theoretically understood, and the basis of wind speed is introduced. The clustering method based on K-means clustering algorithm: only one average wind speed is obtained in steady state, that is, the equivalent is one machine, while under transient conditions, multiple equal-duty machines are obtained and compared with the voltage and power characteristics of detailed wind field. It is proved that the accuracy of wind farm with K-means method is higher. 2. By using the static voltage stability analysis method of P-V U-Q curve, because the traditional P-V curve can not reflect the fluctuation of wind power, the relationship between the different wind power permeability and the static voltage stability limit of Hainan power network in 2015 is calculated. A three dimensional P-V surface voltage safe operation region is established to represent the safety margin of the wind power system, and the maximum allowable access capacity of the system is determined by this method, and the sensitivity analysis index is used for the strong and weak systems. Considering the different operation modes, the influence of increasing wind power penetration on the voltage stability of the system is analyzed. 3. Time domain simulation is an effective method to study voltage stability, and the supporting effect of doubly-fed fan on transient voltage is deduced. The influence of doubly-fed fan on the transient voltage of the system is proved and analyzed on the single-machine infinite bus network. The influence of changing the wind power permeability on the transient voltage stability of the system is simulated by connecting the equivalent wind farm to the grid in Hainan on 2015. Based on the expressions of wind turbine terminal voltage, the influence of wind power permeability, grounding resistance, short circuit location and access form on the transient voltage of the system is studied.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM614

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