Overvoltage by Ferroresonance on a Rural Distribution Feeder: Case Report and Simulation

Abstract

-The objective of this work was to analyze an overvoltage case in a rural distribution feeder belonging to an electrical distribution company in the southeast of the Buenos Aires Province in Argentina. The network was modeled in the Electromagnetic Transients Program, based on the electrical parameters that make up the circuit, in order to evaluate its behavior under various switching and load states. The simulation analysis showed that during certain operation and load situations, the conditions for the overvoltage phenomenon occurred, causing a voltage increase in the single-phase transformer feeding. The guidelines for prevention and control of the phenomenon were provided taking into account the results obtained in the study.Keywords-Overvoltage, ferroresonance, rural electrical distribution, fuse opening, ATPDraw, nonlinear circuits.Resumen--El objetivo del trabajo presentado fue el de analizar un caso de sobretensión en un sistema de distribución de energía eléctrica rural (13,2kV) perteneciente a una Cooperativa de Electricidad del sudeste de la Policía de Buenos Aires, Rep. Argentina. A partir de los parámetros que componen el circuito eléctrico se modeló la red dentro del entorno del programa computacional Electromagnetic Transients Program, con el fin de evaluar su comportamiento ante distintas maniobras de interrupción y estados de carga. El análisis de la simulación demostró que, en ciertas situaciones de operación y carga, se conjugaron las condiciones para la ocurrencia del fenómeno de ferrorresonancia, ocasionando la elevación de tensión de alimentación en transformadores monofásicos. Considerando los resultados del estudio, se brindaron pautas a tener en cuenta para la prevención y control del fenómeno.

Diagnostic approach in assessment of a ferroresonant circuit

“…Moreover, a presented (R)LC circuit structure may be later adapted to many problems emerging when power system is modeled. The designed RLC circuit constitutes a fragment of simplified model of a power system [3,4,8,13].…”

“…n F max (13) where f i(m) , f i(s) voltage or current value for the ith time instance, F max maximum value of the respective waveform. The index m denotes measured values, while s denotes those obtained by simulations.…”

“…The nature of a phenomenon described above and referred to in many research papers [4,[8][9][10][11][12][13][14][15][16] leaves no doubt as to the constant need of studying low-loss circuits containing capacitors and saturable inductors. Taking into account their tendency to become prone to ferroresonance condition, a new and interesting approach to the problem focuses on developing of new detection, diagnostic and monitoring procedures.…”