<p>Actuator dynamics introduce a synchronization disparity between commanded displacements transmitted to the actuator and the actual displacements generated by the actuator, thereby affecting its precision and potentially leading to instability in real-time hybrid simulation (RTHS). This study aims to elucidate the relationship between calculated and measured displacements by analyzing their magnitude and phase in the frequency domain via transformations. The physical implications of these relationships are explored in the context of frequency domain evaluation indices (<i>FEI</i>), the transfer function of actuator dynamics, and delay compensation. Formulations for achieving perfect compensation of actuator dynamics are developed, and an enhanced compensation approach, termed improved windowed frequency domain evaluation index-based compensation (IWFEI), is introduced. The efficacy of IWFEI is assessed using a RTHS benchmark model, with perturbed simulations conducted to validate its robustness. Uncertainties inherent in actuator dynamics are represented as random variables in these simulations. Comparative analysis of the mean values and variances of evaluation criteria demonstrates that IWFEI enables more accurate and robust compensation. Furthermore, strong correlations observed among criteria in the time and frequency domains underscore the effectiveness of the proposed frequency domain-based compensation method in mitigating amplitude errors and phase delays in RTHS.</p>