Small Signal Stability Analysis of a four Machine System with Strategic Placement of Monopolar LCC-HVDC link

This paper presents a small signal stability analysis of Line Commutated Converter, High Voltage Direct Current (LCC HVDC) system when interconnected at different buses in a Kundur two-area four-machine system. The swing equation of a single machine, which was represented as a generator connected to a large infinite network and two incoherent two-area machines were analysed. A time domain simulation study was carried out on the system during a small signal disturbance on a synchronous generator to determine the damping characteristics and the amplitude of oscillations when LCC-HVDC model was connected at different strategic bus on the network. The results show a more quickly damped oscillation and more stable operating mode with HVDC link compare to HVAC lines.