RV COLLEGE OF ENGINEERING TOPIC : MAXIMUM POWER POINT TRACKING
PRESENTED BY Shashikumar v ROLL/USN NO : 52 MAXIMUM POWER POINT TRACKINGR V COLLEGE OF ENGINEERINGDepartment of electronic and communication
Objective What is a solar cell ? a solar cell converts optical energy directly into electrical energy. It is essentially a semiconductor device fabricated in a manner which generates a voltage when solar radiation falls on it.Efficiency of solar cell is less, it only converts 30-40% of energy incindent on it to electrical energy.Need to use solar energy : pollution free maintenance free silent operation long life time.Efficiency of solar cell increased by a technique called maximum power point tracking, by installing this technique we can get additional 20-30% of extra energy.
MethodologyPhase 1 :Introduction to maximum power point tracking (MPPT).Need of MPPT.Different types of techniques for MPPT. perturb and observe technique (P&O) incremental conductance (INC).Phase 2 :Introduction to charge controller and and their need for MPPT.Present and upcoming research in finding most efficient MPPT technique.Modelling of standalone pv system.
IntroductionWhat is MPPT ? It is an electronic system that operates the photovoltaic modules in a manner to extract the maximum power from the system.What is maximum power point ? It is a operating point at which maximum power can be extracted from the system.Usually represented as MPP.The output of solar module is a function of solar irradiance, temperature.Generally MPPT is installed in between PV system and load.Coupling to the load for maximum power transfer may required either providing a higher voltage at lower current or lower voltage at higher current.
Mechanical ComponentDC motorRPM of dc motorDesign of solar panel anti reflection coating
Photo electric effectHelioelectrical process
where Isc is the light - generated current Voc is light generated voltage
Perturb and observe( hill climbing)
The concept behind the P&O method is to modify the operating voltage or current of the PV panel until you obtain maximum power from it.The tracker operated by periodically incrementing or decrementing the solar array voltage.In this we use only voltage sensor,to sense the pv array voltage.Hill climbing method fail under rapid environment change conditions.
Incremental conductanceIncremental conductance uses two voltage and current sensors to sence the output voltage and current pf the pv arrayHere we are sensing both current and voltage simultaneously.hence the error due to change in irradience is eliminated.however the complexicity and cost of implementation increases.
Mathematical Component Incremental conductance Based on fact that slope of P-V zero at MPP. Negetive on right of MPP Positive on left of MPPThe MPP can be tracked by comparing the instantaneous conductance (I/V) to the incremental conductance.
This technique can instantly calculate i/v and di/dv to deduct the direction of the perturbation leading to the MPP.
Programming in CFlow chart of incremental conductance
The algorithms are implemented in a microcontroller or a personal computer to implement maximum power tracking.Micro controller AT89S52 is used to controll & interface,sensors and motor. The microcontroller is low power,high performance,COMS-8 bit micro controller with 8k bytes,Micro controller checks the voltage obtained at various points & stops the panel at maximum voltage point.
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