Fuel cell (FC) systems are appropriate candidates as alternative energy sources for use in stand-alone applications. However, the FC generates an unregulated voltage, which is not suitable in stand-alone application usage solely. This paper presents the control of stand-alone application based on fuzzy PID (FPID) controller. The aim of this paper is designing and controlling a suitable power conditioning unit (PCU) that consists of two DC/DC converter stages and DC/AC inverter. In addition, an analysis of cascade structure based on fuzzy PID controller for a single phase inverter is done and also two feedback control loops are comprised. Inductor current and capacitor voltage are measured and sent through feedback to the inner loop and the outer loop, respectively. Besides, to evaluate the proposed controller robustness, the PCU is considered under step loads as disturbance. Finally, it is shown that the proposed controller has a robust behavior and good transient response. (C) 2015 Elsevier Ltd. All rights reserved.