Abstract: The forced sub-synchronous oscillation (FSSO) incident in Hami, Xinjiang, exhibits novel time-varying frequency characteristics, distinguishing it significantly from conventional negative-damping sub-synchronous oscillations and thus attracting widespread attention. This paper investigates the FSSO generation mechanism and proposes an oscillation suppression strategy based on an adaptive Hamiltonian model. First, the propagation process of inter-grid harmonic disturbances in doubly-fed induction generator (DFIG) systems is analyzed through mathematical modeling. Using an equivalent disturbance equation, we examine the FSSO generation mechanism under disturbance excitation, and through analyzing the relationship between bandwidth stability and damping state, we develop fundamental design principles for suppression strategies. Second, a rotor-side converter (RSC) control strategy is developed by incorporating generalized Hamiltonian theory, and based on the adaptive Hamiltonian model's disturbance suppression and damping compensation capabilities, we propose a comprehensive control framework and oscillation suppression approach. Finally, considering influencing factors including wind speed, line series compensation degree, and the number of operational wind turbines, we establish a wind farm FSSO simulation model that verifies the proposed suppression strategy's effectiveness. Moreover, the actual FSSO case in Hami demonstrates promising engineering application prospects.