Abstract:
The application of photovoltaic (PV) systems increases dramatically since it is clean, sustainable,
and easy to maintain and can be applied on transportation, phone application, on and off-grid
energy production, satellite systems, and in any portable device that require energy. However,
Solar panels have a nonlinear voltage-current characteristic, with a distinct maximum power point
(MPP), which depends on environmental factors, such as temperature and irradiation. In order to
continuously harvest maximum power from the solar panels, maximum power point tracking
(MPPT) plays an important role for PV power pumping systems because it optimizes the power
output for a given set of conditions.
This thesis performs design and performance analysis of fuzzy sliding mode control (FSMC) for
MPPT PV water pumping system. The proposed method controls the duty ratio of a DC-DC boost
converter to produce maximum power from the solar panel and hence the speed induction motor
could rotate with its maximum capacity and more water quantity is obtained. In this work
mathematical modeling of the whole components such as PV panel, DC-DC Boost converter, DC-AC inverter, and the induction motor is individually modeled and then the proposed controller is
designed in MATLAB/ SIMULINK. These individually modeled components and controllers are
connected to generate 24KW power from the PV array and the performance is assessed under
different environmental conditions. The performance of the controllers has been evaluated under
uniform irradiation& temperature, rapidly varying irradiation, sudden change of ambient
temperature, and the sudden variation of load. The performance of the sliding mode control (SMC),
fuzzy logic control (FLC), and FSMC controllers for photovoltaic water pumping systems is
evaluated through simulation studies and compared. The proposed MPPT techniques are able to
track the MPP with the highest efficiency under dynamic and steady-state conditions. Based on
the simulation result FSMC has an MPPT efficiency of 99.13% compared with 80.21% in FLC
and 97.81% in SMC.
Keywords: Boost converter, Fuzzy logic control, FSMC, MPPT, Photovoltaic (PV), Sliding
mode control