90E36 Datasheet, PDF (17/79 Pages) Integrated Device Technology – Poly-Phase High-Performance Wide-Span Energy Metering IC

90E36
POLY-PHASE HIGH-PERFORMANCE WIDE-SPAN ENERGY METERING IC
3.5 MEASUREMENT FUNCTION
Measured parameters can be divided to 7 types as follows:
- Active/ Reactive/ Apparent Power
- Fundamental/ Harmonic Power
- RMS for Voltage and Current
- Power Factor
- Phase Angle
- Frequency
- Temperature
Measured parameters are average values that are averaged among
16 phase-voltage cycles (about 320ms at 50Hz) except for the tempera-
ture. The measured parameter update frequency is approximately 3Hz.
Refer to Table-16.
3.5.1 ACTIVE/ REACTIVE/ APPARENT POWER
Active/ Reactive/ Apparent Power measurement registers can be
divided as below:
- active, reactive, apparent power
- all-phase-sum / phase A / phase B / phase C
- apparent power all-phase vector sum
Altogether there are 13 power registers. Refer to 6.6.1 Power and
Power Factor Registers and the SVmeanT register (98H).
Per-phase apparent power is defined as the product of measured
Vrms and Irms of that phase.
All-phase-sum power is measured by arithmetically summing the
per-phase measured power. The summing of phases can be configured
by the MMode0 register.
The ‘apparent power all-phase vector sum’ is done according to IEEE
std 1459.
3.5.2 FUNDAMENTAL / HARMONIC ACTIVE POWER
Fundamental / harmonic active power measurement registers can be
divided as below:
- fundamental and harmonic power
- all-phase-sum / phase A / phase B / phase C
Altogether there are 8 power registers. Refer to 6.6.2 Fundamental/
Harmonic Power and Voltage/ Current RMS Registers.
3.5.3 MEAN POWER FACTOR (PF)
Power Factor is defined for those cases: all-phase-sum / phase A /
phase B / phase C.
Altogether there are 4 power factor registers. Refer to 6.6.1 Power
and Power Factor Registers.
For all-phase:
PF_all = ^{All_phase_ sum active_pow er}
All_phase_ sum apparent_p ower
The all-phase-sum apparent power selection is defined by the CF2E
SV bit (b6, MMode0).
For each of the phase::
PF_phase = ^{active_pow er}
apparent_p ower
3.5.4 VOLTAGE / CURRENT RMS
Voltage/current RMS registers can be divided as follows:
Per-phase: Phase A / Phase B / Phase C
Voltage / Current
Altogether there are 6 RMS registers.
Neutral Line Current RMS:
Neutral line current can be measured by A/D, or calculated by instan-
taneous value i_N = i_A + i_B + i_C .
Altogether there are 2 N line current RMS registers.
Refer to 6.6.2 Fundamental/ Harmonic Power and Voltage/ Current
RMS Registers.
Function Description
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December 9, 2011