The resonance overvoltages in EHV network

Resonance is a phenomenon that occurs in electrical power systems of all voltage levels. The necessary and sufficient conditions are the framework of scenarios where resonance develops. The capacitors of electrical networks are linear elements. Nevertheless, the inductances may be both type: linear and nonlinear (with ferromagnetic core). Only one resonance steady state may appear in a linear circuit with concrete value of capacitance and inductance. However, it is significant that resonance frequency may be different with the frequency of energy source. In this case, nonlinear inductance is not taken part in resonance circuit directly, but it generates harmonic components. The nonlinear resonance such as ferroresonance is excited in circuit with linear capacitors and nonlinear inductances. All these resonance variants may appear in EHV electrical networks. Some problems of resonance analyses, prediction and elimination in real network are considered in the report.