Abstract: Taking the transfer orbit design of the geosynchronous orbit satellite as mission background, the hybrid chemical electric propulsion orbit transfer was designed and analyzed to address the problems of great fuel consumption of fully chemical propulsion and long transfer time of fully electric propulsion.  Firstly, the influence of inclination and argument of perigee of switching orbit on transfer performance was analyzed. Analysis indicates that inclination should be used as one of the optimization variables. Secondly, the perigee radius, apogee radius and inclination of the switching orbit were used as optimization variables to construct the search grid. Each point in the grid corresponded to one switching orbit. For each switching orbit, a chemical propulsion orbit segment and an electric propulsion orbit segment were computed separately. The chemical propulsion segment was achieved by Lambert transfer, and the electric propulsion segment was achieved by using hybrid method for optimization. Finally, taking fuel consumption and transfer time as design index, exhaustive search for the switching orbits in the search grid was implemented, and the trend of hybrid propulsion transfers in the entire solution space was analyzed. The method proposed provides a family of solutions, filling the gap between the fully chemical transfer solution and fullyelectric transfer solution. The solutions have different combinations of fuel consumption and transfer time, and can be used in future missions.

Key words: geostationary orbit, hybrid chemicalelectrical propulsion, trajectory optimization, orbital maneuver, low thrust