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Hello All,

I am currently hitting a barrier with regards to the basics of this question.

A 50HZ supply is connected to various given impedance's connected in series and parallel. Calculate the value of the load impedance and the maximum power transfer.

Maximum power transfer I understand is basically the Thevenin/Norton equivalent of Rth. But to acquire Rth surely you nee two values of ohms law?

Though THERE IS NO EMF indicated in the question. Is it possible to simply use the frequency given 50Hz and the impedances to calculate the maximum power?

Any help in the right direction would be vastly appreciated

You are not being asked to calculate the maximum power.

You are being asked to calculate the maximum power transfer.

That is the fraction of the power available from the source that can be delivered to the load, i.e. if you can deliver 10% or 30% or x%.

Your task is to find x.

You don't need the EMF of the source because power transfer is a ratio so is independent of the source EMF (or open circuit voltage).

Draw the impedances as a simulatable circuit diagram in CircuitLab (CL).

Assume a 1V rms 50Hz ideal voltage source.

Note that if you set an amplitude of 1V in the sine source in CL, then that sets a peak voltage of 1V, i.e. 2V pk-pk, so for a 1V rms you need to set the amplitude to 1*sqrt(2).

Identify the impedances that constitute the load, ZL.

The rest constitutes the source impedance, ZS.

If you know ZS and ZL, then you can find the power transfer.

You can plot power in CL:

https://www.circuitlab.com/docs/the-basics/#plotting_outputs

https://www.circuitlab.com/docs/expressions/

but that will plot instantaneous power. For the rms you will need to find the average of the plotted power.

Hint: run the sim for a large number of cycles and use a low pass filter.

Be careful if you need to find the power in parallel or series components and think about what the measurement actually means:

http://en.wikipedia.org/wiki/Root_mean_square

Note that if ZS and or ZL are complex then the power will not all be real, i.e. there will be a power factor to take account of. In other words there will be a phase shift between the voltage and the current in the load (and from the source).

BTW, Google and Wikipedia are your friends:

Google for:

maximum power transfer

find:

http://en.wikipedia.org/wiki/Maximum_power_transfer_theorem