One of the market leaders in hydrogen injection systems for internal combustion engines has developed double acting direct injection technology for a wide range of fuel pressures. This thesis outlines the development and validation of a solenoid model which predicts static magnetic forces as well as the development of a dynamic lift model which predicts injector motion and impact forces. The solenoid force model found that iron cobalt can be replaced by iron silicon materials as there performance is comparable. The dynamic lift model shows that the seat and stop impact forces can be calculated which allows engineers to optimize injector designs before prototypes are built. These models allow engineers to optimize the performance and geometric parameters of the double acting technology in preparation of series production.