Influence of Long EHV AC Underground Cables on the Resonance Behavior of the Dutch Transmission System

Abstract

Application of long EHV XLPE underground cables has divers effects on the transient behavior of transmission grids, mainly due to their large capacitive shunt impedance. Low-order resonance frequencies are one of the features of long cables that deserve special attention. This paper investigates the
resonance behavior of partial cable-based EHV networks by simulating a 380 kV double-circuit mixed OHL-cable connection in the future Dutch transmission system. The Sweep Frequency Response Analysis (SFRA) is performed for the distributed frequency-dependent parameter model of the whole Dutch 380
kV grid with and without cables in the case study project. The analysis is carried out for different cabling scenarios (i.e. different cable lengths) and for several sensitivity analyses including the influence of shunt compensation size, shunt
compensation location, and mixed-line configuration on the resonance behavior of the grid. The results are compared in terms of order of first harmonic resonance frequency and number of resonance frequencies. The EMT studies are carried out in the PSCAD environment.