October 28, 2011
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August 21, 2011
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A MODULAR FUEL CELL, MODULAR DC-DC CONVERTER CONCEPT FOR HIGH PERFORMANCE AND ENHANCED RELIABILITY
In this project a modular fuel cell powered by a modular dc-dc converter is proposed. A single phase inverter circuit is used to convert the input dc voltage from the fuel cell into desired ac voltage.
The voltage from the inverter is stepped up to desired voltage using a step-up transformer. A rectifier is used to convert the ac voltage from the transformer into dc voltage. This high dc voltage can be used in heavy loads. Fuel cell stacks produce a dc output with a 2:1 variation in output voltage from no-load to full-load.
Since fuel cells actively convert the supplied fuel to electricity, each cell requires proper distribution of fuel. Also stacking more cells in series decreases the reliability of the system. The proposed concept electrically divides the fuel cell stack into various sections, each powered by a dc-dc converter.
The proposed modular fuel cell powered by a modular dc-dc converter eliminates many of these disadvantages.
- Fuel cells are non toxic. Fuel cells eliminate pollution caused by burning fossil fuels; the only byproduct is water.
- This technique is Pollution free. If the hydrogen used comes from the electrolysis of water, then using fuel cells eliminates greenhouse gases.
- High power output. Since hydrogen can be produced anywhere where there is water and electricity, production of potential fuel can be distributed.
- Long life. Operating times are much longer than with batteries, since doubling the operating time needs only doubling the amount of fuel and not the doubling of the capacity of the unit itself.
- Can withstand high temperatures. Installation of smaller stationary fuel cells leads to a more stabilised and decentralized power grid.
- The maintenance of fuel cells is simple since there are few moving parts in the system.