Resistive Ferroresonance Limiter for Potential Transformers

Abstract

The ferroresonance or nonlinear resonance is a complex phenomenon, which may cause overvoltage in the electrical power system and endangers the system reliability and operation. The ability to predict the ferroresonance in the transformer depends on the accuracy of the transformer model used. In this paper, the effect of the new suggested ferroresonance limiter on the control of the chaotic ferroresonance and duration of chaotic transients in a potential transformer including nonlinear core losses is studied. To study the proposed ferroresonance limiter, a single phase 100 VA, 275 kV potential transformer is simulated. The magnetization characteristic of the potential transformer is modeled by a single-value two-term polynomial. The core losses are modeled by third order power series in terms of voltage and include core nonlinearities. The simulation results show that the ferroresonance limiter has a considerable effect on the ferroresonance overvoltage.

Memristor emulator – a nonlinear load for reduction of ferroresonance in a single-phase transformer

“…However, with electronic or tuned circuits, the damping becomes effective only for the designed frequency. The various analyses of the literature revealed that the mitigation circuit damps the oscillations along with its own limitations (Ben et al , 1999; Kong and Ahoui, 2014; Tahir et al , 2013; Pattanapakdee and Banmongkol, 2007; Hamid et al , 2012; Hamid, 2012; Wenxima et al , 2014). The memristor emulator is designed as the load for the mitigation of ferroresonance.…”

Smart solid‐state ferroresonance limiter for voltage transformers application: principle and test results

“…Ferroresonance has occurred if CB and disconnector D S2 are opened, disconnector D S1 is closed and power system experiences no-load or lightly load conditions. In this model, the magnetisation current is modelled by two terms seventh-order polynomial, which has been obtained and introduced previously in [5,7,8,19,21] as…”

“…Ferroresonance has occurred if CB and disconnector D S 2 are opened, disconnector D S 1 is closed and power system experiences no‐load or lightly load conditions. In this model, the magnetisation current is modelled by two terms seventh‐order polynomial, which has been obtained and introduced previously in [5, 7, 8, 19, 21] as where, λ = Nφ , N is the number of VT coil turns and per unit value of coefficient a is 3.42 and b is 0.41 [5]. In this case, the power system equivalent circuit is a ferroresonance circuit as shown in Fig.…”

“…In this case, the power system equivalent circuit is a ferroresonance circuit as shown in Fig. 2 [5, 7, 8, 19, 21]. In this model, resistor R models the transformer core losses.…”

“…The inductance is usually related to a transformer and the capacitance belongs to a system capacitance or circuit breaker (CB) grading capacitance [1][2][3][4]. In some power systems, ferroresonance may include some types of nonlinear oscillations referred to fundamental, sub-harmonic and chaotic nonlinear resonance or ferroresonance [5][6][7][8]. This ferroresonance overvoltage may involve different frequencies in the power system and cause power quality problems.…”