This paper presents the positive feed-forward control (PFFC) scheme for the distributed buck conversion system with the multiple non-ideal voltage sources. Since the employed voltage sources are non-ideal, the output voltage level of the individual voltage source varies with the output current of the individual voltage source. Moreover, the employed voltage sources with the different electrical characteristics have different power ratings. With the use of the conventional negative-feedback control (NFBC) schemes, the maximum input power of the individual power module cannot be limited at the maximum output power rating of the corresponding voltage source. Therefore, the proposed PFFC scheme is used to ensure the maximum power harvesting function for the individual power module. Furthermore, the average current-mode control (ACMC) associated with PFFC is able to ensure the stability for the power converter. Finally, the experimental results show that the paralleled buck power module system achieves the maximum power harvesting function.