STPM14 STMicroelectronics, STPM14 Datasheet - Page 34

• Manufacturer Part Number: STPM14
• Description: (STPM11 - STPM14) Single phase energy metering IC
• Manufacturer: STMicroelectronics

Energy calculation algorithm
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[Eq. 10]
[
[Eq. 11]
The signals process flow is the same as shown in the previous case, and even with the
formulas above, the result is the same.
The absence of any AC component allows a very fast calibration procedure. Averaging the
readings of several line periods is not needed. The active energy measurement is already
stable after one line cycle. Moreover the digital calibration allows saving time and space
compared to the hardware calibration made with resistor strings.
i
′ ′
) (
t
=
∫
i
′
) (
t
⋅
dt
=
t i
) (
=
−
I
⋅
sin(
ω
t
+
ϕ
)
STPM11/12/13/14