Application of Equivalent Linearization Algorithm on Voltage Transformer Protection during Fundamental Resonance in Power System

Ferroresonance is a common phenomenon and the type of the fundamental resonance occurs frequently in the power system. The overvoltage and overcurrent generated by the resonance will damage the voltage transformer (VT) or other facilities, and lower the power quality in the power system. In this paper, an adapted equivalent linearization algorithm is applied to analyze the fundamental resonance of a typical resonance circuit in the power network for the VT protection. The resonance region and safe region of the circuit can be obtained by the algorithm. On the base of the equivalent linearization algorithm the fundamental resonance can be avoided, and VTs can be efficiently protected from the resonance