In this work the maximum power point tracking of solar photovoltaic panels that are
operating in the same area for a common load but subjected to an unequal solar insolation levels.
It is proposed that a separate DC to DC converter is used for each of the panels. Sliding mode controller
is adopted for the MPPT. The MATLAB SIMULINK simulation and the experimental verification
validates that the proposed idea harvests more power than the common optimised duty
cycle that is used in a single power converter.
Methods: In the existing scheme where a number of panel are operating in parallel a common DC
to DC converter is used. For the purpose of MPPT and optimisation technique is used to arrive at
the duty cycle to be adopted in the common DC to DC converter. Such a method guarantees the
overall maximum possible power output for that particular method using a single DC to DC converter
with a single duty cycle. It does not guarantee the maximisation of the power output of the
individual solar PV panels which is the actual maximum power harvestable for the given environmental
condition. In the proposed technique, applicable to solar trees where a number of panels
are physically arranged in different angles so as to harvest maximum power all through the day, it
is more effective to use individual dc to dc converters with individual duty cycles. In this work the
sliding mode control based on the PV terminal voltage is adopted.
Results: The proposed idea is simple, no rigorous mathematical implications, requires less number
of sensors, and requires no explicitly PWM circuits. It can be used readily in real life applications.