Re: Boost Converter Efficiency in a Practical Design calcula
Iin and Iout are both average values since the efficiency calculation refers to the steady-state values of variables.
You should use current probes to measure Iin and Iout. Normally these clamp around the wire that you want to measure the current in. Depending on your current probe, you might or might not need an external amplifier. If your load is just a resistance, just measure the voltage across it and determine the current by Vout/Rload.
You can also try to put a small resistor (with an appropriate power rating) in series with the branch you are trying to measure the current in. Obviously, if you just have a load resistor at the output just use the method above. You can put a small resistor at the input current.
Now, if you are using a good power supply for the input voltage and an electronic load for you load resistance, you may be able to read off the currents on these instruments directly. This all depends on what equipment you have.
Best regards,
v_c