Integrated DC ‑ AC Converter as Power Conditioner for Fuel Cell Based System

This paper presents a new integrated power conditioner topology for power supply systems based on fuel cells. The proposed converter is based in the ZVS active clamp full bridge boost converter but controlled with sinusoidal pulse width modulation technique. The proposed fuel cell power conditioner is intended for stand-alone ac power generation and low voltage fuel cell input. The main characteristic of the proposed topology is the use of fewer components when compared to the conventional two-stage power conditioners approach, so the cost is lower. In addition, the total efficiency is increased by reducing the power processing stages. Therefore, it is expected that the proposed integrated power conditioner topology could be effectively utilized for fuel cells applications. The paper presents a compressive analysis of the main characteristics of the fuel cell which will determine the design parameters for the power conditioner. Also, detailed operations of the integrated topology is introduced. In order to validate the proposed approach a 900 watts prototype was implemented. The paper presents experimental results under several operating conditions.