The built-in voltage overshoot, slow response speed, poor voltage stability and load disturbance exist in the aerospace three-stage generator. To solve these problems, a two-degree-of-freedom fractional order PID (2DOF FOPID) voltage regulation controller optimized by gray wolf hybrid particle swarm optimization (GWO-PSO) is designed on the basis of double loop voltage regulation structure. The two-degree-of-freedom control is used to enhance the ability of anti-interference and target tracking. The fractional order control is used to make the parameter setting more flexible and insensitive when the parameter of the controlled object changes, and the control performance of the system is improved. The improved GWO-PSO starts the search process with the mechanism of GWO algorithm, and then uses PSO algorithm to improve the position of grey wolf, so as to balance the ability of local search and global development of the algorithm. Then the improved algorithm is used to optimize the parameters of 2DOF FOPID controller. Simulation results show that the designed controller has the advantages of fast response and small overshoot. It improves the dynamic and static performance and anti-interference ability of the generator.