Abstract:Due to the high specific impulse, the application of electric propulsion technology in GEO orbit transfer can greatly reduce the fuel mass, improve payload mass ratio and prolong mission life. In order to solve the trajectory optimization and guidance problem of all-electric propulsion GEO satellite, the indirect method is used to obtain the numerical solution of fuel-optimal GEO orbit transfer with low thrust, and a polynomial curve fitting method is proposed to fit the optimal trajectory. The polynomial curve is simple in form and can be stored and used onboard the satellite as a reference orbit. On the basis of polynomial reference orbit, a closed-loop guidance strategy using piecewise constant thrust by tracking the reference orbit is established. Under the condition of constant thrust, there is an analytic relationship between the control structure and the change of the orbit elements, which simplifies the design of guidance law. The multiple-revolutions transfer problem is decomposed into multiple single orbit optimization problems. The results show that the proposed guidance strategy has high tracking accuracy and consumes 7% more fuel than the optimal trajectory. The control structure of the guidance strategy is simple and easy to implement.