Post on 16-Apr-2017
Maximum Power Point Tracking for Photovoltaic (PV) Arrays
CSUN SITE Program 2015 The Short Circuits
Outline
● Introduction● Maximum Power Point Tracking● Modeling and Simulation● Experimental Setup● Conclusion● Questions
Photovoltaic Cells
● PV (PhotoVoltaic) Cell: Converts solar energy into electrical energy
Reference http://www.fsec.ucf.edu/en/consumer/solar_electricity/basics/how_pv_cells_work.htm
Advancements in Efficiency
Approach
● Learn the concepts behind PV power generation
● Understand the individual components of a PV Array system
● Simulate a PV Array using MATLAB’s Simulink
● Analyze optimal conditions for PV Array usage
● Introduce the DC-DC converter
● Utilize the MPPT algorithms and implementation
● Temperature● Irradiance● Shade● PV material
Factors That Affect PV Arrays
Mathematical Model Developed in Simulink
PV Array Electrical Model in Simulink
MPP Change Due to Temperature
Voltage (V)
273 K296 K303 K MPP
Pow
er(W
)
Power(W) vs. Voltage (V)
MPPMPP
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
0.5
2
2.5
Higher cell temperature leads to lower power output.
PV Curves With Different Solar Irradiation
Higher irradiance leads to high power output.
Pow
er (W
)
Voltage (V)0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
0.2
0.4
0.6
0.8
1
1.2
1.4
L = 0.5L = 1L = 2L = 4
MPPT Algorithm Theory
60 Ω
30 Ω
100 Ω
5 Ω
∞Voltage (V)
Pow
er (W
)
Power (W) vs. Voltage (V)
Max power
What is Maximum Power Point Tracking?
● MPPT finds the maximum power of a PV Array and maintains that power output for optimal performance
● Without the MPPT the DC-DC converter would be inefficient
● Maximizes Efficiency of PV Array
http://www.leonics.com/
PV Array System Components
Ipv
Vpv
Ipv
DC/DC Step down Converter (Buck)
� Vo=D*Vin D: Duty Cycle
Finding MPP with variable Duty Cycle
1. Perturb and Observe (P&O)2. Incremental Conductance (IC)3. Three point way comparison4. Short Current Pulse5. Constant Voltage
MPPT Algorithms
Perturb & Observe (P&O)
Voltage (V)
Pow
er (W
)
Power (W) vs. Voltage (V)
Max power
A
BC
D E
1 2 3 6 7 80
0.1
0.6
0.5
Incremental Conductance (IC)�
Incremental Conductance (IC)
Voltage (V)
Pow
er (W
)
Power (W) vs. Voltage (V)
Max power
A
CB
D
1 2 3 6 7 80
0.1
0.6
0.5
Complete PV model using P&O Algorithm
MPPT for Perturb & Observe MethodDeveloped in Simulink
MPPT for the IC Method developed in Simulink
P&O Method: IC Method:MPPT Power Curve
Experimental Setup
Solar Array8 Volt - 310 mA
Halogen Lamps Decade Resistor Range used: 1 - 1K
Video
Comparison between Methods
Perturb & Observe Condition Incremental ConductanceOscillates around the
maximum power pointOscillations in the graph Doesn’t Oscillate as much
as P&O toward the maximum power point
Oscillates around the maximum power point
Finding the exact maximum point
Able to find the Maximum power and stay at the point
Simpler algorithm Structure of the Algorithm More complex algorithmDoes not adjust as fast as
IC methodRapid changes in
Irradiation Able to find the exact
maximum point rapidly
More efficient with temperatures
Varying Temperature Doesn’t adjust as rapidly as P&O method
Lower irradiation Irradiation and Efficiency Higher irradiationNot as efficient as the IC
modelBuck-Boost Converter Rapidly adjusts to converter
Conclusion
● Learned about parameters influencing energy conversion of Photovoltaic(PV) arrays.
● Recreated the mathematical and electrical model of PV arrays in MATLAB Simulink.
● Learned about the general concept of Maximum Power Tracking (MPPT).
● Successfully redesigned and compared two MPPT algorithms Perturb and Observe
(P&O) and Incremental conductance (IC).
● Understood the concept of DC-DC voltage conversion and its usage in voltage and
power regulation of PV arrays.
● Experimentally acquired data using LabView software and observed and verified the
theoretical concept of MPPT algorithms.
Acknowledgements
● Dr. Kourosh Sedghisigarchi
● Dr. Vibhav Durgesh
● Robert Morris
References
[1] A. Dolara; R. Faranda; S. Leva. “Energy Comparison of Seven MPPT Techniques for PV Systems” in J. Electromagnetic Analysis & Applications, 2009, 3: 152-162
[2] A.P.Yadav, S. Thirumaliah and G. Harith. “Comparison of MPPT Algorithms for DC-DC Converters Based PV Systems” International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering Vol. 1, Issue 1, July 2012
[3] H.N.Zainudin and S. Mekhilef, "Comparison Study of Maximum Power Point Tracker Techniques for PV Systems" Proceedings of the 14th International Middle East Power Systems Conference
(MEPCON’10), Cairo University, Egypt, December 19-21, 2010
[4] R.Faranda and S. Leva, "Energy Comparison of MPPT techniques for PV Systems," WSEASTransaction on Power Systems, vol. 3, pp. 446-455
Questions?