What is Maximum power: Definition and 83 Discussions

Maximum power point tracking (MPPT) or sometimes just power point tracking (PPT), is a technique used commonly with wind turbines and photovoltaic (PV) solar systems to maximize power extraction under all conditions.
Although it primarily applies to solar power, the principle applies generally to sources with variable power: for example, optical power transmission and thermophotovoltaics.
PV solar systems exist in many different configurations with regard to their relationship to inverter systems, external grids, battery banks, or other electrical loads. Regardless of the ultimate destination of the solar power, the central problem addressed by MPPT is that the efficiency of power transfer from the solar cell depends on the amount of sunlight falling on the solar panels, the temperature of the solar panel and the electrical characteristics of the load. As these conditions vary, the load characteristic that gives the highest power transfer efficiency changes. The efficiency of the system is optimized when the load characteristic changes to keep the power transfer at highest efficiency. This load characteristic is called the maximum power point (MPP). MPPT is the process of finding this point and keeping the load characteristic there. Electrical circuits can be designed to present arbitrary loads to the photovoltaic cells and then convert the voltage, current, or frequency to suit other devices or systems, and MPPT solves the problem of choosing the best load to be presented to the cells in order to get the most usable power out.
Solar cells have a complex relationship between temperature and total resistance that produces a non-linear output efficiency which can be analyzed based on the I-V curve. It is the purpose of the MPPT system to sample the output of the PV cells and apply the proper resistance (load) to obtain maximum power for any given environmental conditions. MPPT devices are typically integrated into an electric power converter system that provides voltage or current conversion, filtering, and regulation for driving various loads, including power grids, batteries, or motors.

Solar inverters convert the DC power to AC power and may incorporate MPPT: such inverters sample the output power (I-V curve) from the solar modules and apply the proper resistance (load) so as to obtain maximum power.
The power at the MPP (Pmpp) is the product of the MPP voltage (Vmpp) and MPP current (Impp).

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  1. PhysicsTest

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    I equated dP/dR to 0 and find the solution for R. Is the solution correct?
  2. jisbon

    Engineering Computing the Maximum Power delivered to a Resistor

    Hi all, Checking my answers here as it doesn't seem to match with the answers given to me. Would appreciate if anyone could point out the mistakes I made. First I will compute Rth. Offing all independent sources, applying a known voltage across R (in this case 1v) and using mesh analysis...
  3. jisbon

    Engineering Finding the maximum power delivered using Thevenin's theorem

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  4. N

    Mechanical engineering: Maximum Power Transmitted by a V-Belt Assembly

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  5. M

    Engineering Homework: Rx=? to get maximum power transfer at point M

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  6. Adrian Tudini

    Computer models that predict the maximum power of a chemical reaction

    Given a balanced chemical equation, can we predict using computer models the maximum power of the chemical reaction? Thanks.
  7. Physics lover

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  8. Mzzed

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  9. J

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  10. D

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  11. peroAlex

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  12. O

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  13. A

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  14. I

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  15. G

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  16. C

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  17. JordanHood

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  18. M

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  19. H

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  20. Q

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  21. I

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  22. J

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  23. G

    Find Maximum Power to Resistor R

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  24. O

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  25. M

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  26. M

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  27. A

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  28. B

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  29. N

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  30. A

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  31. A

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  32. gfd43tg

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  33. gfd43tg

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  34. T

    Engineering Understanding Maximum Power in Circuit: Comparing Load and Circuit Approaches

    Homework Statement What is the difference between maximum power in load and maximum power by load and circuit? The Attempt at a Solution I know max power in load is when Rth (Thevenin) = RL(load). And the equation to find power in load is (Vth^2)/(4*Rth). Not sure how to find max...
  35. T

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  36. S

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  37. A

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  38. F

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  39. C

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  40. E

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  41. A

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  42. G

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  43. P

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  44. D

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    Hi, I'm investigating maximum power transfer in a AC circuit. I understand that for maximum power transfer the reactance both cancel each other out and the value of the source resistance and load resistance have to be equal. I have also found some formulas to prove this. what i would like...
  45. G

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    Hello everyone! I have a general question about how to find out the maximum power transfer to a load resistor with a negative Thevenin Resistance (Rth < 0). I know for positive cases, P = R*(Vth/(R + Rth))^2, in which R is the load resistor connected to the Thevenin equivalence circuit, and Pmax...
  46. JJBladester

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    Homework Statement "If the load voltage at the output of a circuit keeps going up as the load resistance is increased, why doesn’t the load power keep going up as well?" Homework Equations The maximum power transfer theorem states: A load will receive maximum power from a network...
  47. B

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    Hi everybody, Below is a circuit that I am investigating. All the components are linear, nothing fancy here. My goal is to maximize the average power P dissipated in the resistor Re. To this aim, I am only allowed to play with the angular frequency ω of the voltage source and with the value...
  48. M

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  49. O

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