Abstract: Abstract：This paper is mainly concerned with the closedloop drive control of flexible solar arrays. Based on a modal identity of the flexible structure, the generalized statespace formalism of the flexible solar array drive system is derived. By the Lyapunov’s method, an outputfeedbackbased PD control is developed, and the regularity and impulsefreeness of the closedloop system are investigated in the framework of generalized system theory, followed which the admissibility of the control system is guaranteed. The effectiveness of the closedloop control algorithm is verified by the numerical simulations and comparison with the openloop algorithm. Finally, conclusions are drawn and a possible research topic is proposed.

Key words: Keywords：solar array drive assembly, flexible solar array, modal identity, generalized system, admissible control