Abstract:
Industrial countries, such as South Africa, rely heavily on energy sources to function
profitably in today’s economy. Based on the 2008 fossil fuel CO2 emissions South Africa was
rated the 13th largest emitting country and also the largest emitting country on the continent
of Africa, and is still increasing. It was found that fuel cells can be used to generate electricity
and that hydrogen is a promising fuel source. A fuel cell is an energy generation device that
uses pure hydrogen (99.999%) and oxygen as a fuel to produce electric power. A
regenerative fuel cell is a fuel cell that runs in reverse mode, which consumes electricity and
water to produce hydrogen.
This research was aimed at designing and constructing an optimised control system to
control the hydrogen pressure in a proton exchange membrane regenerative fuel cell. The
hydrogen generated by the fuel cell must be stored in order to be used at a later stage to
produce electricity.
A control system has been designed and constructed to optimise the hydrogen pressure
control in a regenerative proton exchange membrane fuel cell. An experiment that was done
to optimise the hydrogen system included the effects that the cathode chamber pressure has
on the production of hydrogen and the most effective method of supplying hydrogen to a
storage tank. The experiment also included the effects of a hydrogen buffer tank on the
output hydrogen pressure and if the system can accommodate different output pressures.
It was found that the cathode chamber pressure doesn’t need to be controlled because it has
no effect on the rate of hydrogen produced. The results also showed that the flow of
hydrogen need not to be controlled to be stored in a hydrogen storage tank, the best method
is to let the produced hydrogen flow freely into the tank. The hydrogen produced was also
confirmed to be 99.999% pure. The system was also tested at different output pressures; the
control system successfully regulated these different output pressures.
Description:
Thesis (M. Tech. - (Engineering: Electrical, Department: Electronic Engineering, Faculty of Engineering and Technology))--Vaal University of Technology.
