Maximum Power Theorem


Maximum Power theorem

Maximum power is transferred to the load when the load resistance equals the Thevenin resistance as seen from the load (RL = RTh).

The Thevenin equivalent ckt. is useful in finding the maximum power a linear circuit can deliver to a load.


For a given circuit, and Vth and Rth are fixed.

By varying the load resistance the power delivered to the load varies.



For maximum power supply 



When we differentiates the Rl=Rth

Load resitance equals to thevenine resistance


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