ECS-9810167 Czarnecki The project will employ the concept of a hybrid adaptive compensation for loads with nonsinusoidal currents developed, tested on prototypes and reported earlier. According to this concept, a compensator is built of an adaptive passive compensator, which compensates the reactive power and balances the system, and an active compensator, which compensates fast varying components of the load current. Such a hybrid structure is considered in the literature of the subject as the structure that could overcome power limitations while keeping compensation speed and reduce the cost of the compensator. The compensator is controlled by a hybrid algorithm, i.e., at the same time, in the frequency-,and in time-domain. A new control algorithm that will enable compensation of loads with non-periodic currents will be developed in this research project. Compensators for improving power factor and power quality are designed and specified in terms of active and reactive powers, rms values and harmonic rms values. These values have to be measured or calculated to provide input data for the compensator control. However, these quantities are not defined in systems with non-periodic waveforms. Therefore, the control will be based on a concept of time-varying quasi-powers measured over a time window of the duration of the supply voltage period. The research is a continuation of the PI's studies on power phenomena, measurements and compensation in three-phase nonsinusoidal systems and will rely on theoretical studies, computer modeling of circuits with non-periodic currents and energy flow in such circuits, as well as on laboratory experiments with laboratory prototype of a compensator of time-variant loads. Methods of compensation of loads with non-periodic currents developed in this project will contribute to more effective use of electric energy, to reduction of disturbances and increased reliability of equipment, and thus to reduction of extra cost involved with the supply of variable speed drives, industrial robots, arc furnaces or welders. Computer modeling of circuits with non-periodic currents, studies on properties of quasi-powers and their use in developing the control algorithm of a hybrid compensator will contribute to the knowledge base of electrical engineering. The results of this project will be disseminated through published reports. This project will provide the subjects for two M.Sc. and for one Ph.D. theses, thus three electrical engineers will acquire a deep knowledge and skill in compensating loads with non-periodic currents. Since a new course on power quality and its improvement was initiated at the ECE Dept. at LSU, with a laboratory under development, the prototype developed in this research will be used for education purposes. Also, Research Assistants in this project will be employed next in the development of the Power Quality Lab. All of this will contribute to dissemination of the research results, as well to enhancement of education on power quality. Moreover, the arrangement of a panel discussion at the PES IEEE Meeting on loads with nonperiodic currents and their compensation will be initiated to enhance a partnership between experts in this area.
