# 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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I equated dP/dR to 0 and find the solution for R. Is the solution correct?
2. ### Engineering Computing the Maximum Power delivered to a Resistor

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

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

Hi, after calculations I end up in the circuit below¨ (Thevenin equivalent) So now I have to say Rth=RL and I will find Rx ?The initial circuit is this: Thanks
6. ### 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. ### Maximum power in this resistor circuit

My attempt-: So the resistance is coming to be negative.Can anyone tell me my mistake.Thanks.

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9. ### Maximum power is transferred when load R = Source R ?

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12. ### Maximum Power Transfer Ideal Transformer

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13. ### Using the maximum power transfer theorem

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14. ### Current at maximum power - PV cell

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15. ### Maximum power factor of three phase receiver

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16. ### Optimizing Power on a Resistor: Finding the Maximum Power

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17. ### Maximum power from a battery with source resistance

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18. ### Max Power Transfer Homework: Find Ro for Max Power

Homework Statement Hey guys, I have been struggling on this problem for a while now and was hoping I could get a little help What is wanted is the maximum value of Ro for maximum power. Homework EquationsThe Attempt at a Solution Knowing that the Maximum power transfer to Ro would be when...
19. ### Modeling a Black Box Circuit for Maximum Power Transfer

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20. ### Max Power Transfer: Optimal Load for Piezo & EM Gen

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21. ### Maximum power of circuit with dependent voltage source

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22. ### Finding Maximum Power Delivered to Resistor

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23. ### Find Maximum Power to Resistor R

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24. ### Max Power Transfer to Ro: Percentage Explained

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25. ### Maximum power developed by a lift

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26. ### Find the resistance for maximum power transfer

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27. ### What is the Maximum Power Transfer Theorem?

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28. ### Engineering Thevenin equivalent of circuit and maximum power transfer

Homework Statement Find the Thévenin equivalent of the circuit and the required value of the load for maximum power transfer for Z = 15 + j24 Ω . Homework Equations Voltage divider equation and Z_{in} = Z_{load} 'complex conjugate' for maximum power transfer. The Attempt at a...
29. ### Engineering Maximum power transfer in circuit

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30. ### Maximum Power Point Tracking for Solar Cell

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31. ### Maximum Power Transfer problem

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32. ### Engineering [Circuits] Finding maximum power

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33. ### Engineering Maximum power transfer in a circuit

Homework Statement a) What value of the load resistor RL will extract the maximum amount of power from the circuit below? b) How much power will that be? Hint: you need to use both the concepts of Thevenin equivalent circuits and maximum power transfer. Homework Equations The...
34. ### Max Power Transfer: Source Voltage & Load Explained

Hello, I was wondering, why is it that when calculating the maximum power transfer, the source voltage is the thévenin voltage, and not the actual source? What we call the load is arbitrary, no?
35. ### Engineering Understanding Maximum Power in Circuit: Comparing Load and Circuit Approaches

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36. ### Maximum power and maximum torque

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37. ### Network Maximum Power Transfer Calculation

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38. ### Maximum Power Transfer for Z = 12+24 Ohms

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39. ### Find the maximum power of power plant

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40. ### Maximize Average Power Transfer with Impedance ZL - Circuit Analysis Homework

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41. ### Maximum Power Transfer for Coupled Emitter Follower

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42. ### Maximum power transfer and kirchoffs

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43. ### Engineering Electrical Circuit Question - Maximum Power Dispated in Resistor

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44. ### Maximum power delivered by a solar cell to a resistive load

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45. ### I'm investigating maximum power transfer in a AC circuit

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...
46. ### Maximum Power Transfer with Negative Thevenin Resistance?

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...
47. ### Maximum Power Transfer Theorem

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...
48. ### Maximum power transfer theorem leading to erroneous result Why?

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...
49. ### How Can We Use a Bread Board to Demonstrate the Maximum Power Theorem in Lab?

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Hello. I need to design a matching circuit to provide maximum power transfer from a generator with impedance Zg to a load with impedance ZL. The matching circuit has a length of transmission line with impedance Z0 and short circuit or open circuit stub with impedance Zs. I need to design with...