A control system for an onboard oxygen generating system (OBOGS) includes a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS. The gain control selectively switches between unbalanced and balanced bed cycling modes of the OBOGS to produce a target oxygen concentration based on demand. A corresponding method includes providing a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS, controlling the OBOGS to operate in the unbalanced bed cycling mode when a low demand is placed on the OBOGS whereby the gain control provides a short bed cycle and a corresponding long cycle of a fixed cycle time, and switching the OBOGS to operate in the balanced bed cycling mode when a high demand is placed on the OBOGS. The balanced bed cycling mode operates at a decreased bed cycle time.