Power applications signal power

Applications of signal processing tools in a power systems course
Francisco Jurado and Manuel Valverde Department of Electrical Engineering, University of Jaén, Linares (Jaén), Spain E-mail: fjurado@ujaen.es, mvalver@ujaen.es
Abstract The scope of a modern electrical engineering curriculum presents a challenging problem. It is quite difficult to design a well rounded and all-encompassingcurriculum in a rapidly evolving field such as electrical engineering. In this paper, signal processing tools are presented that allow the student to see immediately the advantages and limitations of these techniques for electric power ‘quality’. Three signal processing techniques are considered: discrete Fourier transforms, wavelet filters, and discrete short-time Fourier transforms. The paper explainshow the course material and teaching style respond to various requirements for an integrated design experience. Keywords harmonics; power engineering education; power quality

The electric power industry is undergoing a major change, both technically and politically. To prepare future engineers for the challenges they will face, educators must upgrade the power engineering curriculum to reflectchanging trends in the industry. One way to respond to the needs of industry is to introduce engineering students to technologically current approaches while students are still in the classroom setting. This may be accomplished by combining traditional and new material. Electric power quality can be loosely defined as a measure of how well electric power service can be utilized by customers.1–6 Whenwave shapes are irregular, voltage is poorly regulated, harmonics and flicker are present, or there are momentary events that distort the usually sinusoidal wave, and power utilization is degraded. One refers to these conditions as degradation of power quality. The subject of power quality engineering truly encompasses most areas of electric power engineering, from generation to utilization, andpower quality engineering has been a topic of interest from the inception of the power engineering field. Some contemporary factors have made it the subject of more focused interest, however. The advent and widespread use of high-power semiconductor switches at utilization, distribution, and transmission levels has made non-sinusoidal load currents more common. Deregulation of the power industry hasmade power quality a distinguishing feature of distribution service. Losses in transmission and distribution systems have come under greater scrutiny in recent years, and certain types of power quality degradation result in losses. For all these reasons, electric power quality has become an important topic in power engineering. At the graduate level, research needs, more advanced application areas,and university hiring have added impact the doctoral programme. At master level, there is a special need in the electric power quality area: this is a subject that relates to maintaining sinusoidal voltage wave shape at all load buses. Increasing reliability and selling power quality related services, such as unbundled services, are specialized
International Journal of Electrical EngineeringEducation 41/1

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niche needs in industry. Equipment manufacturers have also entered the commercial sector in the marketing of new power system components for power quality enhancement. Power quality has special importance in an educational programme because it teaches modelling and interactions of large-scale systems. Measurement and instrumentationalso come into play. Power quality issues are relatively new in power education programmes because of commercial interest in these areas and because the advent of high power electronic switched loads has resulted in power quality degradation in some cases. The role of modeling in power quality assessment and analysis is crucial. For this reason, modelling is one focus of graduate level power...