To achieve accurate localization of oscillation sources in direct-drive wind farms connected to the grid via a VSC-MTDC system

this paper proposes an oscillation source localization method based on interaction energy and Hamiltonian paths. First

a dynamic energy model of the grid-connected system is established. By analyzing the interaction energy between subsystems

positive and negative factors characterizing their connections are extracted to quantify the impact of each link on the system stability. Then

a Hamiltonian graph topology of the system is constructed

with each edge assigned interaction energy weights. The global optimal path is solved using a backtracking algorithm to identify the oscillation initiation and propagation links. Finally

experimental validation is carried out on the RT-LAB hardware-in-the-loop simulation platform. The results demonstrate that the voltage outer-loop d-axis subsystem of the sending-end converter VSC1 and the phase-locked loop (PLL) subsystem of the receiving-end converter VSC3 are identified as the key links causing system oscillations. This study provides a new analytical approach and a theoretical basis for oscillation tracing and suppression in complex power-electronics-dominated grid-connected systems.