Abstract—Ferroresonance is a nonlinear resonance, which may cause overvoltages in the electrical power system. This paper studies the effect of circuit breaker shunt resistance on the control of ferroresonance in a voltage transformer while the core losses of the VT core are highly nonlinear. It is expected that this resistance generally can cause ferroresonance ‘dropout'. For confirmation this aspect simulation has been done on a one phase voltage transformer rated 100VA, 275kV. The magnetization characteristic of the transformer is modeled by a single-value two-term polynomial with q=7. The simulation results reveal that considering the shunt resistance on the circuit breaker in the case of nonlinear core losses, exhibits a great mitigating effect on ferroresonance overvoltages. Significant effect on the onset of chaos, the range of parameter values that may lead to chaos along with ferroresonance overvoltages has been obtained and presented.

Index Terms—Circuit breakers shunt resistance, nonlinearcore losses effect, chaos, bifurcation, ferroresonance, voltage transformers.

Hamid Radmanesh is with Electrical Engineering Department, Shahab Danesh Institute of Higher Education, ghom, Iran(e-mail: Hamid.radmanesh@aut.ac.ir).
Matin Nademi and M. Nademi are with Department of Electrical Engineering, Islamic Azad University, Takestan Branch, Takestan, Iran(e-mail: hrbscstudent@gmail.com; mam.nademi@gmail.com).

Cite: Hamid Radmanesh, Matin Nademi, and Maryam Nademi "Circuit Breaker Shunt Resistance Effect on Ferroresonance in Voltage Transformer Including Nonlinear Core Losses," International Journal of Computer and Electrical Engineering vol. 4, no. 5, pp. 743-747 , 2012.