A computer based data acquisition system for teaching transients and switching phenomena and performing research on digital protection

The authors present a computer-based model for demonstrating and teaching fault-induced transients, switching phenomena, and power with particular reference to teaching and advancing the concepts of digital protection of power systems. The design and implementation of a digitally controlled switching circuit is described. A data-acquisition system for sampling the current and voltage waveforms used in conjunction with a special interface with a VAX 11/750 or a personal computer to analyze the data is presented. An example of qualitative study for inrush current and fault-induced transients in a power transformer is shown. A mathematical model for the inrush current in a power transformer that accounts for time-varying and random parameters and that offers a basis for developing methods for digital protection of power transformers is presented. Finally, the integration of the model in teaching senior and graduate-level subjects related to power-system transients and protection is summarized.<>