An Isolated High Gain Quadratic DC-DC Boost Converter for Fuel Cell Application

An isolated high gain quadratic DC-DC boost converter for fuel cell application is proposed in this paper. The proposed converter has several advantages over other isolated and non-isolated DC-DC converters such as having relatively higher voltage gain at comparatively lower operating duty ratio. This not only helps to prevent the core saturation, but also lower the required turns ratio for a certain voltage boosting which prevents the drop in converter efficiency due to higher turns ratio. In addition to the aforementioned advantage, this converter has lower voltage stress on the active switches and diodes. The operating principle of the proposed converter has been explained and the relation between voltage gain in term of duty ratio is derived and presented in brief. Further, the expression for voltage stress across the active switches are presented. A control strategy of the proposed converter to control the load voltage of it only is also explained in brief. In order to validate the working of the proposed converter, a MATLAB Simulink model of it has been prepared, and exhaustive simulation study has been performed. The parameter of the proposed converter which are selected for the simulation study are as follows: input DC voltage: 24 V, load voltage: 400 V, operating duty ratio: 0.42, transformer turns ratio: 2, output power: 500 W.