Abstract:
A review of existing modular interleaved converters for turbulent renewable
energy sources including wind and solar power shows that with a small change
in environment factors such as wind speed and light intensity, there is a
much greater change in the power generation at the supply. Existing topolo gies largely discuss the use of static defined modular interleaved topologies,
where the relation between the input and output of each interleaved module
remains constant. This means that the conversion from the unstable input
supply to a stable reliable output requires large passive components with an
a similar variation in the duty cycle. In this thesis, we discuss the advan tages of different modular configurations including the Input Series Output
Series (ISOS), Input Series Output Parallel (ISOP), Input Parallel Output
Series (IPOS) and Input Parallel Output Parallel (IPOP). We then compare
existing techniques for power conversion and how each of the modular con figurations perform with these systems. We then propose a control scheme to
dynamically change between the configurations to best achieve their respec tive advantages. This helps reduce the size of the passive circuit components;
the capacitors and inductors, by reducing the current and voltage stress on
each component. The control scheme also reduces the control effort required
by the active components e.g. the switches. Specifically, the Quasi-Z Source
converter is interleaved due to its superior applicability over conventional
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converters. The use of Quasi-Z Source modules further simplifies the control
strategy, reduces source stress with lower passive component ratings. It also
requires a reduced number of the active components to operate which further
increases efficiency. The simulation is perform on MATLAB Simulink using
a turbulent input supply to verify the effectiveness of the proposed converter
and the results are then displayed.
