Hugo Dias
01/31/2023, 11:57 AMStefan Schippers
01/31/2023, 2:01 PMrms
value of a power.
RMS is the (square root) average of squared values, taking the square
of instantaneous power and taking the average is nonsense.
If you want to get the average power do:
let pow = i(v1) * v(a,b)
meas tran cap_avg_pow avg pow from=600u to=800u
If a
and b
are the nodes of a capacitor and i(v1)
is the current flowing into the capacitor in steady state the average power into the capacitor is zero. See example below. Instantaneous power into or out a capacitor is apparent, it has net value zero.
See ngspice calculated value (in blue) at the bottom.