<p>This paper presents a Thomson coil actuator (TCA) for high voltage direct current (HVDC) protection with emphasis on rapid interruption of fault current. An axisymmetric 2D finite element analysis (FEA) model with coupled electrical and mechanical dynamics and a time-difference scheme is developed for early design exploration and is shown to agree closely with a 3D reference for the initial configuration. With this validated 2D model, a genetic algorithm (GA) using the weighted-sum method and non-degradation constraints is employed to improve both closing and opening while keeping the original drive conditions. The optimized design delivers higher maximum force and shorter completion time. The optimization uses the 2D model in the loop and independently verifies the final geometry with 3D analysis. Flux density maps from 2D and 3D analyses exhibit similar saturation near the excitation coil and the mover, which are consistent with the adopted modeling approach. The results indicate an accurate and time-efficient approach to TCA design for HVDC protection.</p>