Abstract: A self-centering variable friction damper is proposed to enhance structural seismic resilience. The damper employs helical springs and wedge blocks to achieve a positive correlation between self-centering capacity and energy dissipation. Based on its construction and working principle, a restoring force model was developed and validated through friction tests and damper experiments. 15 refined finite element models were established for the detailed parametric analysis after verification. Test results show that friction coefficients remain constant under 30 kN~60 kN preload, and that the damper exhibits typical "flag-shaped" hysteresis loops with excellent energy dissipation and self-centering capabilities. Simulations indicate that: energy dissipation and bearing capacity increase with wedge block sets, with friction coefficient \mu _2 , with spring stiffness and, with initial pre-compression length, but decrease with wedge angle, and with friction coefficients \mu _1 and \mu _3 ; increasing spring stiffness and pre-compression enhances both energy dissipation and self-centering. The sensitivity analysis identifies the friction coefficient \mu _2 (comprehensive sensitivity 1.38) and wedge block sets (1.11) as dominant parameters for hysteretic performance regulation.