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

• Applicant: Professor Dr.-Ing. Peter Schegner
• Subject Area: Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
• Term: from 2009 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 115465649

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.

• DFG Programme: Research Grants
• Participating Person: Dr.-Ing. Jan Meyer