BL6533 SinglePhaseEnergyMeterICwithLCDDriver
When V(v)= ±110mV, cosϕ=1, over the arrange of 5%Ib to 800%Ib, the nonlinear error should be less
than 0.1%.
3) Positive And Negative Real Power Error
When the positive real power and the negative real power is equal, and V(v) =±110mV, the test current
is Ib, then the positive and negative real power error can be achieved by the following formula:
eNP%=|[(eN%-eP%)/(1+eP%)]*100%|
Where: eP% is the Positive Real Power Error, eN% is the Negative Real Power Error.
4) Power Supply Monitor
BL6533has the on-chip Power Supply monitoring The BL6533 will remain in a reset condition
until the supply voltage on VDD reaches 4 V. If the supply falls below 4 V, the BL6533 will also be reset
and no pulses will be issued on CF.
ꢀ THEORY OF OPERATION
ꢀ
Principle of Energy Measure
In energy measure, the power information varying with time is calculated by a direct multiplication of
the voltage signal and the current signal. Assume that the current signal and the voltage signal are cosine
functions; Umax, Imax are the peak values of the voltage signal and the current signal; ωis the angle
frequency of the input signals; the phase difference between the current signal and the voltage signal is
expressed asφ. Then the power is given as follows:
p(t) = Umax cos(wt)× Imax cos(wt +
If φ=0:
ϕ )
Umax
I
p(t)
=
max [1
+ cos(2wt)]
2
If φ≠0:
p(t) = Umax cos(
ω
t)× Imax cos(ωt + Φ)
= Umax cos( t)×
ω
[
Imax cos( t)cos(Φ) + Imax sin(
ω
ω
t)sin(Φ)
]
U
max Imax
=
=
=
=
[
ω
]
U
max I
ω ω
max cos( t)sin( t)sin(Φ)
1+ cos(2 t) cos(Φ) +
2
Umax
I
Umax Imax
max [1+ cos(2
ω
t)]cos(Φ) +
sin(2ω
t)sin(Φ)
t)sin(Φ)
2
2
Umax Imax
Umax Imax
cos(Φ) +
cos(Φ) +
[
cos(2
ω
t)cos(Φ) + sin(2
ω
]
2
2
Umax Imax
Umax Imax
cos(2ωt + Φ)
2
2
P(t) is called as the instantaneous power signal. The ideal p(t) consists of the dc component and ac
component whose frequency is 2ω. The dc component is called as the average active power, that is:
Umax Imax
P =
cos(ϕ )
2
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9/9/2009
Total 10 Pages
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