The momentum management controller is used for large spacecrafts with orbit maintenance of long life which only have small difference in three-axis main inertia. It should be guaranteed that one inertia axis of spacecraft is strictly perpendicular to the orbital plane. Then, an inertial reference coordinate system for momentum management is established. It is observed that the drift of long-period orbit factors has an approximate linear relation to time, which leads to a linear increase of output offset of the momentum control. Therefore, the failed reasons in the design of the optimal control law are analyzed, and the state equation is augmented with internal model principle to compensate the perturbation, then the optimal quadratic regulators with pole placement method is used to design the controller according to the state space equation. Finally, semi-physical simulation validates the controller. The results show that the design of the compensation method is feasible, and the long term stability of attitude and angular momentum are achieved.