Ferroresonance Study in Voltage Transformers ConnectingMetal Oxide Varistor
Hamid Reza Radmanesh, Mahdi Jafari, Matin Nademi, Maryam Nademi · International Journal of Computer and Electrical Engineering · 2012
This paper studies the effect on Metal Oxide Varistor (MOV) on ferroresonance phenomenon in iron core voltage transformer (VT).It is expected that MOV generally cause ferroresonance 'dropout'.Time-domain study has been carried out to study this effect.Simulation has been done on a voltage transformer rated 100VA, 275 kV.The magnetization characteristic of the transformer is modeled by a single-value two-term polynomial with order seven.The core loss is modeled by linear resistance.The simulation results reveal that connecting the MOV in parallel to VT, exhibits a great mitigating effect on ferroresonance overvoltages.Phase plan, voltage waveforms, along with bifurcation diagrams are also derived.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.