I have a signal which I want to calculate its effective value. The signal is a voltage value read on a 33.3m\$ \Omega \$ resistor connected series to a 220V AC power line. My aim is to calculate the reactive power transferred on the power line.
(Frequency is 50Hz. Vertical scaling is 10 mV/square for both signals.)
I obtained the "Filtered Signal" by the circuit below:
The filtered signal can be assumed to be a DC voltage level. Its value read from the oscillator screen represents 150mA current level through the current sensing resistor. This is the average value of the current flowing on the power line, isn't it so? However, I need the effective value of the current in order to calculate the power. Since the current on the line is not sinusoidal, I cannot calculate the effective value from those simple AC voltage wave formulas.
So, what can I do? I'm stuck at this point. Is there any way of calculating the effective value of this current from these available data, or any way of calculating the power directly?