Abstract: A four-motor driven internal force loading mechanism was designed to meet the centric loading requirements of a cylindrical split-type component, which can apply a total loading force of over 15 000 N to the structural component. However, during the actual loading process, asymmetries in the structure can cause loading eccentricity, resulting in relative movement between the structural components and affecting the assembly quality. To address this issue, a PD control method is proposed based on model feedforward for synchronized motion control of multiple motors. The method establishes a dynamic model between the input signal and the angular velocity of an AC servo motor, and designs feedforward compensation based on the target speed from this model to enhance the response speed of synchronized operation control of multiple motors. Additionally, PD feedback control parameters are designed based on the model to achieve high-precision synchronized control. Experimental results indicate that compared to traditional cross-coupling synchronization algorithms, the PD synchronization control algorithm based on the model reduces synchronization errors by about 40% and effectively improves motor synchronization.