计及电能质量问题的低压配电网损耗计算模型研究

发布时间：2018-02-02 16:16

本文关键词： 电能质量三相不平衡电压偏差谐波网损 ETAP　出处：《郑州大学》2017年硕士论文　论文类型：学位论文

【摘要】：网损是反映电网经济性运行水平的一项重要指标。随着我国低压配电网电能质量问题的日渐严重,由电能质量问题引起的低压配电网附加网损也越来越多。由低压配电网产生的损耗,占我国配电网总损耗的一半以上,而其中电能质量问题对低压配电网损耗的影响更是不容忽视。低压负荷多以居民用电为主,目前我国居民用电占全国总用电的12%左右,美国为36%,因此我国居民用电还有很大的发展空间和节能空间。准确地计算低压配电网损耗,并分析出各种问题所引起损耗的大小,对于合理地选取治理方案,实现电力行业的节能降损将有十分重要的意义。首先,论文在进行配电网损耗计算前对三种低压配电网中最常见的电能质量问题(三相不平衡、电压偏差、谐波)进行了详细的分析。然后,为了研究电能质量问题对低压配电网损耗的影响,论文采用等值电阻法对低压配电网进行了简化,分别对三种电能质量问题影响下变压器和线路的损耗特性进行了深入的分析。在分析过程中引入了相角不平衡、动态不平衡、谐波不平衡的概念,并给出了相应的计算方法。然后,为了使低压配电网损耗计算的准确度更高,论文对传统的等值电阻法进行了改进,推导出了考虑电压偏差和谐波的等值电阻计算方法。论文采用ETAP电力分析软件搭建了简单的0.4 kV低压配电网仿真模型,分别分析了三种电能质量问题对低压配电网损耗的影响。接着,论文对代表日的选取方法进行了介绍,分析了考虑特殊负荷日的代表日Q型聚类分群法。最后,在分析三种电能质量问题对低压配电网损耗影响的基础上,提出了同时考虑三相不平衡、电压偏差和谐波的低压配电网损耗计算模型,并通过实例验证了该模型能提高低压配网损耗计算的准确度。此外,论文还对每种电能质量问题所造成的配电网损耗的大小进行了分析,对于电能质量问题的治理具有指导意义。
[Abstract]:Network loss is an important index to reflect the economic operation level of power network. With the development of power quality problem in low-voltage distribution network in China, the problem of power quality is becoming more and more serious. The additional network loss of low voltage distribution network caused by power quality problem is more and more. The loss caused by low voltage distribution network accounts for more than half of the total loss of distribution network in China. However, the influence of power quality problem on the loss of low-voltage distribution network can not be ignored. The low-voltage load is mainly used by the residents. At present, the consumption of electricity in our country accounts for about 12% of the total power consumption in the country, and in the United States it is 36%. Therefore, there is still a lot of room for development and energy saving. The loss of low-voltage distribution network is calculated accurately, and the loss caused by various problems is analyzed. The realization of energy saving and loss reduction in power industry will be of great significance. First of all, the most common power quality problems (three-phase imbalance, voltage deviation) in the three low-voltage distribution network before the distribution network loss calculation. Then, in order to study the influence of power quality problem on the loss of low voltage distribution network, the equivalent resistance method is used to simplify the low voltage distribution network. The loss characteristics of transformers and lines under the influence of three kinds of power quality problems are analyzed in depth. The concepts of phase angle imbalance, dynamic imbalance and harmonic imbalance are introduced in the process of analysis. Then, in order to make the loss calculation of low voltage distribution network more accurate, the traditional equivalent resistance method is improved. The calculation method of equivalent resistance considering voltage deviation and harmonic is deduced. A simple simulation model of 0.4 kV low voltage distribution network is built by using ETAP power analysis software. The influence of three kinds of power quality problems on the loss of low voltage distribution network is analyzed respectively. Then the method of representative day selection is introduced and the representative day Q clustering method considering special load day is analyzed. Finally. On the basis of analyzing the influence of three kinds of power quality problems on the loss of low voltage distribution network, a calculation model of loss of low voltage distribution network considering three phases imbalance, voltage deviation and harmonics is proposed. An example is given to verify that the model can improve the accuracy of loss calculation of low-voltage distribution network. In addition, the loss of distribution network caused by each power quality problem is analyzed in this paper. It is of guiding significance for the management of power quality problems.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM74

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