17-04-2013, 04:22 PM
Interleaved Boost DC-DC Converter for Fuel Cell Application
Interleaved Boost.docx (Size: 139.69 KB / Downloads: 30)
Abstract
Fuel cell converts chemical energy into electrical energy. A fuel cell electric vehicle has higher efficiency and lower emissions when compared to internal combustion engine vehicles. Fuel cells are a major part of fleet of low emission vehicles. For more optimisation of fuel cell dc-dc converter is used. In this paper, it is proposed a way to overcome the drawback of poor output voltage in fuel cell by adjusting the duty cycle of boost converter. In order to meet the voltage, current and power requirements dc-dc converter is used. The major challenge in designing a boost converter is how to handle high current at the input and high voltage at the output. Thus an interleaved boost dc-dc converter topology is proposed for stepping up high voltage for high power application. In this paper a new approach for interleaved boost converter controller’s synthesis, based on dynamic evolution control theory is presented. Then the performance of the proposed topology is tested through simulation.
Introduction
Fuel cell is mainly used in fuel cell powered electric vehicle. To meet the voltage requirements of electric vehicle, fuel cell is interfaced with the interleaved boost dc-dc converter. Interleaved boost converter differs from conventional boost converter in handling high input current and high output voltage efficiently at various duty cycles. Especially at lower duty cycles Rms ripple current in the input inductor and output capacitor is very high which causes in increasing the losses. And makes the conventional boost converter inefficient. Moreover an additional emf is induced in the practical circuits due to the parasitic inductance and capacitance which makes the design of devices complicated as they have to withstand the emf induced due to parasitic ringing. An effective way to overcome this is by using an interleaved boost dc-dc converter in which total input current is divided into two parallel paths, and thereby reducing voltage stress across each switch.
Conclusion
The performance of conventional and interleaved boost converters is observed and compared. The voltage ripple in interleaved boost converter is found to be less than that of conventional. Through dynamic evolution control output voltage is maintained constant irrespective of duty cycle.