Influence of Cables on Power Transmission Network Frequency Response

Harmonic resonance is an important factor to be considered in a power transmission networks during connection of remote generation units with high-voltage cables (e.g. wind or solar power plants etc.). It is known that cable characteristics differ from characteristics of conventional overhead lines. Cable capacitance is far higher than capacitance of an equivalent overhead line, what can potentially lead to the low resonant frequencies which may be triggered by various switching events, such as transformer or shunt reactor energization etc. In this paper, possible consequences of power plant connection to transmission network with long HVAC cable are analysed, with regard to harmonic resonance and frequency response of the network. The research has been conducted on developed model of the power transmission network in the software for calculation of electro-magnetic transients EMTP-RV.