Flyback efficiency calculation: RMS or AVERAGE power?

[edaenrico]

Hi,

I'm a bit confused.

I'm measuring the efficiency of my off-line 230 V flyback converter.

I sampled the mains voltage Vin which is a sinus wave.

I sampled the Input current flowing from the mains into the converter which is a non linear curve.

To evaluate the efficiency I need to evaluate the input power.


QUESTION:
Which of the following formulas should I use?

AVERAGE POWER
(1 / T) * integral from 0 to T {Vin (t) * Iin (t)} dt

RMS POWER
SQRT [(1 / T) * integral from 0 to T {Vin (t) ^2 * Iin (t) ^2} dt]

Thanks,
Enrico Migliore

 

[FvM]

There isn't a thing like "RMS POWER".

The first equation is right for transferred real power, the second is nonsense.

 

[treez]

Use a power meter which will do it for you. eg PM1000 etc