The metrology module generates the following accumulated reactive power (Q) quantities: Q_A, Q_B,
Q_C, Q_A_F, Q_B_F, Q_C_F, Q_N and Q_N_F.
They are in units of [VAR samp-scaled]. They are scaled accumulated reactive power quantities in
the whole integration period. They are calculated according to the following
formula:
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Where, V’_x_samplei is ith filtered phase voltage value of phase x
in present integration period; V’_avc_samplei is ith
filtered phase voltage value of the active voltage channel (according to
STATE_FLAG.TIMING_Vx) in present integration period; I’’_x_samplei
is ith filtered phase current value of phase x in present integration
period; V’_x_samplei, V’_avc_samplei and
I’’_x_samplei have additional 90 degree phase difference;
x = [A, B, C]; N is the number of samples in the last measurement interval.
They are used to calculate the reactive power. In the case of the neutral channel, it is useful
for calculating the angle of the neutral current.
Q_x and Q_x_F
are stored in sQ23.40 format.
