This paper addresses the optimal impulsive control problem of the coplanar formation reconfiguration in a near-circular orbit using impulsive-thrust. This paper introduces a semi-analytical approach of primer vector analysis. For three or four-impulse transfers, semi-analytical solutions of optimal primer vector histories are derived from the necessary conditions of local optimality. The semi-analytical approach is different from the conventional heuristic primer vector analysis in that it utilizes the semi-analytical solutions of optimal primer vector histories. This approach reduces the number of unknown transfer parameters because the necessary conditions of optimality are already satisfied. If the solution exists, boundary conditions determine remaining unknown transfer parameters for given optimal primer vector history. Based on the semi-analytical approach, a global search algorithm has been developed to find global optimal solutions. Various simulations demonstrate that the semi-analytical global search algorithm discovers global optimal solutions satisfying the well-known Lawden's necessary conditions. Moreover, it is found that two different approximate solutions satisfy Lawden's necessary conditions.