Abstract
This paper presents the development of a complete solution to enable transmission lines to operate asymmetrically (i.e. operation with disconnected phase) with and without pre-fault power restoration. First, a power line model for the analysis and control of current flow during asymmetric operation of transmission lines is developed. This model includes ground wires, which are used to facilitate zero-sequence current flow. For high fidelity modelling, each span of the transmission line is represented. A 200km, 500kV line is used as case study. Second, a phase-to-ground fault is then introduced at the midpoint of the line, after which the faulted phase is disconnected, and asymmetric operation is achieved using E-STATCOMs (located at the line extremities) equipped with advanced control methodologies that compensate the circulation of negative and zero sequence currents. The proposed solution is validated through simulation.