含分布式光伏电源的配电网短路电流仿真研究

发布时间：2018-06-06 14:17

本文选题：分布式发电 + 光伏电源模型　；参考：《华北电力大学》2015年硕士论文

【摘要】：目前,以太阳光能为能量来源的光伏发电技术已经日趋成熟,并且达到了大规模商业和工业化应用的水平。可以预见,在未来的一段时期内,各国电网中将会出现大量的光伏并网发电电源。光伏电源的接入,一方面有效地缓解了各国,尤其是以我国为代表的经济发展迅速、对能源需求量巨大的国家的用电紧张局面；另一方面又不可避免地造成了对传统电网的影响。由于光伏电源本身的输出电压低、单个装置的发电容量小,因此一般直接接入配电网络中,因而会对传统的配电网络造成各方面的影响。本专题从配电网络短路故障分析的角度出发,研究光伏电源并网后,对配电网络短路故障造成的影响,希望能为今后光伏电源的并网与运行规则制定提供参考意见。本文利用各种仿真实验来验证本文所提出的光伏电源模型及其控制器设计的正确性,研究了仿真结果是否与传统电力系统分析所得到的结论相符,在验证模型正确性的基础上,今后将把该模型推广至其他光伏并网项目的研究与应用中。其次,利用在仿真软件中搭建的光伏电源电路模型进行各种仿真实验,研究光伏电源并网后,对传统的配电网络短路电流计算与分析所造成的影响,仿真结果表明：短路故障期间,光伏电源的短路电流会迅速达到饱和值,短路故障期间,光伏电源模型的各个环节能够正确地响应外部扰动,通过对不同因素在短路故障期间对光伏电源输出电流的影响的分析可知,光伏电源所采用的模型、并网结构、出口处是否有并联滤波电容等因素并不会对光伏电源在短路故障期间的输出电流造成明显的影响,光伏电源并网后虽然改变了传统配电网络的结构,但其对网络中短路电流的分布与大小所造成的影响并不明显,且这种影响均符合传统短路故障分析所形成的已有结论：距离故障位置越近,短路期间输出电流越大；渗透率水平越高,贡献的短路电流越大；不对称短路故障时也会输出负序电流。
[Abstract]:At present, photovoltaic (PV) power generation technology with solar energy as energy source has become more and more mature, and has reached the level of large-scale commercial and industrial applications. It can be predicted that there will be a large number of grid-connected photovoltaic power sources in the power grid in the future. On the one hand, the access of photovoltaic power has effectively alleviated the shortage of electricity in all countries, especially in the countries where China is the representative of the rapid economic development and huge demand for energy. On the other hand, it inevitably causes the influence on the traditional power grid. Because the output voltage of photovoltaic power supply itself is low and the generating capacity of a single device is small, it is usually directly connected to the distribution network, which will affect the traditional distribution network in all aspects. From the point of view of short-circuit fault analysis of distribution network, this paper studies the influence of photovoltaic power supply on short-circuit fault of distribution network after grid-connected, and hopes to provide reference for future grid-connected photovoltaic power supply and operation rules. In this paper, a variety of simulation experiments are used to verify the correctness of the proposed photovoltaic power supply model and its controller design. The simulation results are in accordance with the conclusions of the traditional power system analysis. On the basis of verifying the correctness of the model, this paper studies whether the simulation results are consistent with the conclusions of the traditional power system analysis. The model will be extended to the research and application of other photovoltaic grid-connected projects in the future. Secondly, using the photovoltaic power circuit model built in the simulation software to carry out various simulation experiments, the influence of photovoltaic power grid connection on the traditional short-circuit current calculation and analysis of distribution network is studied. The simulation results show that the short circuit current of photovoltaic power supply will reach saturation value rapidly during short circuit fault, and each link of photovoltaic power supply model can respond to external disturbance correctly during short circuit fault. Through the analysis of the influence of different factors on the output current of photovoltaic power supply during the short-circuit fault, we can know that the model of photovoltaic power supply, grid-connected structure, Whether there are parallel filter capacitors at the outlet will not have a significant impact on the output current of photovoltaic power during short-circuit fault. Although the structure of the traditional distribution network has been changed after the photovoltaic power is connected to the grid, However, its influence on the distribution and size of short-circuit current in the network is not obvious, and this effect accords with the existing conclusions of traditional short-circuit fault analysis: the closer to the fault location, the greater the output current during short-circuit; The higher the permeability level, the greater the contribution of short circuit current, and the negative sequence current will be output when asymmetric short circuit fault.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM713

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