Systematic Analysis of Electrical and Climatic Environment and their Impact on Power Quality in Public LV Networks

电能质量分为电压质量和电流质量。两者都是时间和地点相关的，可以用不同的参数和指标来表征。影响电能质量的不同因素可分为电气环境和非电气环境。电力环境一方面由所连接的用电和发电设备的类型和数量（用户拓扑和发电拓扑）来描述，另一方面由低压配电网的拓扑和技术参数（网络拓扑）来描述。非电环境包括气候参数的影响，如温度或太阳辐射。该项目的目标是基于合适的参数，系统地识别和分类环境影响因素与电能质量之间的相关性。这项工作的一个基本要求是一个由协调的度量活动创建的综合数据库。最后，对基于上述电气和气候环境影响因素的电能质量估计器的可行性进行了评估。在之前的研究中，成功地实现了基于拓扑和天气指数的特定地点的电流质量表征。因此，介绍了一种确定拓扑和天气相关质量曲线的新方法。最初的研究表明，对于仅由一种类型的消费者（例如仅住宅）和具有明显不同天气条件的天数（例如仅太阳）组成的消费者拓扑，预计最重要的关系。因此，迄今为止的研究活动仅限于这些条件。在进一步的工作中，分析扩展到由不同消费类别混合组成的地点（例如住宅和办公室或商店），以及天气条件不太明显的日子。此外，应通过比较具有类似消费者拓扑结构的测量站点的特定站点质量配置文件，开发特定于消费者拓扑结构的质量配置文件。测量活动的继续能够对评估长期趋势的方法进行详细的分析。此外，这还允许对可伸缩性效应进行研究。该效应描述了用户数量与特定电能质量参数（例如电流谐波）水平之间的关系。主要重点放在住宅拓扑上，因为不同地点之间的客户（家庭）数量的差异是最显著的（从10个到几百个）。这些结果为从表征电力和气候环境的指标推断电能质量的方法的可行性研究提供了坚实的基础。这个所谓的电能质量估计器可以基于专家系统，人工神经网络。

Power Quality is divided in voltage and current quality. Both are time- and site-dependent and can be characterized by different parameters and indices. The different factors with impact on Power Quality can be assigned either to the electrical or the non-electrical environment. On one hand the electrical environment is described by the type and number of the connected consuming and generating equipment (consumer topology and generation topology) and on the other hand by the topology and technical parameters of the low voltage distribution grid (network topology). The non-electrical environment includes i.a. the impact of climatic parameters, like temperature or solar radiation. Goal of the project is the systematic identification and classification of correlations between the environmental impact factors and Power Quality based on suitable parameters. An essential requirement for the work is a comprehensive database that is created by a coordinated measurement campaign. Finally the feasibility of a Power Quality estimator based on the above mentioned impact factors of electrical and climatic environment is assessed.In the previous research a site-specific characterization of current quality based on topology and weather indices was successfully realized. Therefore a new method for the determination of topology- and weather-dependent quality profiles was introduced. Initial studies had shown that most significant relationships are expected for consumer topologies consisting of only one type of consumers (e.g. only residential) and days with distinctively different weather conditions (e.g. only sun). Therefore the research activities up to now were limited to these conditions. In the further work analyses are extended to sites that consist of a mixture of different consumer categories (e.g. residential and office or shops) as well as to days with less distinctive weather conditions. Furthermore consumer topology-specific quality profiles shall be developed by comparing the site-specific quality profiles for measurement sites with similar consumer topology. A continuation of the measurement campaign enables in-detailed analyses of methods for assessing long-term trends. In addition this allows the research on scalability effects. This effect describes the relation between the number of consumers and the level of a particular power quality parameter (e.g. current harmonics). Main focus is put on residential topologies, because the variance of number of customers (households) between different sites is most significant (some ten up to several hundred). Altogether the results provide a substantial basis for a feasibility study on methods to infer from indices characterizing electrical and climatic environment to power quality with an adequate accuracy. This so called Power Quality estimator can e.g. be based on expert systems, artificial neural networks.