Experimental Validation of Multiconductor Cell Analysis by Overhead Line Field Measurements

Multiconductor Cell Analysis (MCA) is a matrix algorithm computing the electrical steady-state regime of any asymmetrical multiconductor system. This paper presents two experimental validations of MCA, which are carried out by two measurement campaigns performed in two different areas of Italy: on the Extra High Voltage (EHV) double-circuit OverHead Line (OHL) Dolo-Venezia Nord (18 km long) and on Suvereto-Montalto di Castro (120 km long) EHV OHL. By considering the double-circuit configuration of these lines, it has been assessed the impact of one inducing circuit, kept in service, on the other circuit, kept out of service, for the evaluation of induced voltages and currents. The induced circuit experiences induced voltage magnitudes ranging from about 4 kV to 30 kV when it is open at both ends, whereas the induced voltages are negligible but the current magnitudes ranging from 10 A to 28 A when it is grounded at both ends. The maximum mismatch between measurements and MCA results is 8,6% of the induced voltage magnitude of the phase closest to the earth. This mismatch is theoretically explainable by considering that this phase is the more subjected to the presence of unknown proximity objects along the route which could alter the electric field. One more time, comparisons between computations and measurements confirm the very good agreement between MCA and the physical behavior of asymmetric multiconductor systems.