Bewley Diagrams Revisited via Visualization

The paper applies the well-known red-green-blue (RGB) coloring method to visualize traveling waves initiated by switching events or faults occurring in power systems. The three-phase voltage profile along a given transmission line is obtained first. This profile is then converted into a colored picture by assigning different colors to phase signals according to their intensity. An interesting outcome of repeating this process for each time step is the emergence of the Bewley diagram which is commonly used to illustrate the behavior of traveling waves in space-time. The main contribution of the paper is to show that RGB coloring of phase signals reveals essentially the same profile as the one obtained by using the aerial mode of the signals transformed into the modal domain. Furthermore, it discusses how this result can possibly be useful in applications such as fault location.

I. Introduction

Understanding the transient behavior of the power networks during a fault or switching is of critical importance for power system protection, control and power quality analysis. So far, studies focus on accurate modeling of various power system components such as transmission lines, transformers, switching equipment, rotating machines as well as the control systems that interact with them. Significant work also exists in the area of simulation methods, most of which are developed to be used in the time domain. The commonly used simulation tool which provides numerical solutions for power system electromagnetic transients in time domain is electromagnetic transients simulator [2]. Development and wide availability of this tool lead to better understanding of complex transients and their effects on power system operation.