A Comprehensive Study Approach for Evaluation of Resonance and Ferro-Resonance in HV Substations A Case Study: Khuzestan Regional Electric Company

Resonance and ferroresonance in power systems are categorized as two destructive phenomena especially in HV networks which their occurrence are being initiated in consequence of a power system event. Also, Ferroresonance phenomenon may be initiated by non-power system event such as lightning strike. Hence, the study of resonance and ferroresonance requires an exhaustive evaluation of possible network events in different network configurations. In each event, the analysis of network voltages is conducted based on identified allowable limits by IEEE 519 standard as an evaluation critera. In this paper, a novel comprehensive study approach is proposed for study of ferroresonance phenomena in power networks. The proposed approach comprises different steps including substation equipment modeling, EMT simulation of the probable switching events, evaluation of correspondence results, and finally detecting the probable ferroresonance occurrence. Furthermore, a novel approach for resonance study is also presented. Voltage and current limits are implemented to define an impedance criteria for performing resonance evaluation of network buses. Findings – The proposed method is implemented for study of resonance and ferroresonance in all HV substations of the Khuzestan regional electricity network. By performing the proposed evaluations, the probable condition which may lead to resonance and ferroresonance occurrence are identified. The results are highly valuable for network operators in prevention of unintended overvoltages occurrence.