A dynamic model, a simulator, and an optimization procedure were developed for small oxygen pressure swing adsorption units with different equalization configurations, top-to-top equalization (TE), bottom-to-bottom equalization (BE), and cross equalization (CE), and three different commercial adsorbents, Oxysiv 5 and Oxysiv 7 from UOP and Sylobead MS S 624 from Grace Davison. These units' cycles have the peculiarity of having the pressure history dependent on the product flow rate, which makes them more difficult to simulate and optimize than the classic Skarstrom cycle. The units' performances (product recovery and power consumption) using each adsorbent and equalization type were compared for cycles with the same pressure ratio. The simulation results were shown to be in agreement with the experimental data obtained with Oxymat 3, an oxygen concentrator from Weinmann. The optimization procedure lead to an improvement of the unit's performance.