Purpose <p>The demand for controlled magnetic actuators is increasing, serving a wide range of applications that include structure resonance tuning, active suspension, and tunable vibration absorbers. This paper introduces an analytical model for a variable-flux permanent magnet actuator (VFPM), consisting of a diametrically magnetized permanent magnet (PM) assembled with two static ferromagnetic poles and a movable ferromagnetic core. The magnetic flux intensity is modulated by adjusting the angle of the PM.</p> Methodology <p>The mathematical model is derived based on Maxwell’s equations and incorporates the physical properties of the actuator, including its dimensions, geometry, nonlinear magnetic characteristics of the PM, and leakage factors. An experimental setup was built to evaluate the actuator’s performance and calibrate the model. The resulting model is both accurate and computationally efficient compared to the square-law relationship and finite element models commonly reported in the literature. The proposed VFPM is integrated with a cantilever beam structure for structural resonance tuning. An experimental setup is built to validate the resonance tuning concept, and a finite element model of the setup is used to calculate the natural frequency.</p> Result and Conclusion <p>The tested VFPM generates a controllable magnetic force of up to 35 N, successfully tuned by the PM orientation angle and air gap, without the need for continuous electric power. The agreement between the analytical and experimental results, with an average deviation of 5%, confirms the model’s suitability for actuator design and control. Furthermore, the VFPM’s capability for tuning the natural frequency of a cantilever beam is demonstrated. The close agreement between analytical and experimental results shows a tuning range of up to 44% of the original natural frequency, with average natural frequency deviation of 1%.</p>