Computing voltage and current amplitude and average power

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Sudarshan on 13 Aug 2020
Commented: hosein Javan on 19 Aug 2020
Hello,
I have three sinusoidal waveforms namely, voltage, current, and power acquired using an oscilloscope which I then have connected to my computer that runs Matlab. I need to compute the voltage and current amplitudes and the average power using the following formulae.
1. Voltage Amplitude =
2. Current Amplitude =
3. Average Power =
where, represent the period, instantaneous current and voltage respectively. How do I use the waveforms obtained via the oscilloscope to find the above amplitudes and power?
Sudarshan on 18 Aug 2020
@Image Analyst.
Please find the arrays for the current, voltage and power in the attached .mat file.
hosein Javan on 18 Aug 2020
if you're using simulink, you don't have to export then analyze them. use the tools that I mentioned in the answer and you should be fine.

hosein Javan on 13 Aug 2020
if they are 3-phase, use clarke transformation. it will give you the amplitude and phase the dividing by sqrt(2) yield the rms value. multiplying V_rms*I_rms = P_average.
if they are single phase. and you know the instantaneous frequency, use sliding average "movmean" function to calculate it. there are simulink blocks available for such task.
if they are single phase and you don't know the instantaneous frequency, then you have to use "PLL" to measure phase or frequency to calculate rms values.
Sudarshan on 19 Aug 2020
Thank you hosein Javan.
hosein Javan on 19 Aug 2020
you're welcome.