PQM-700 Operating Manual
34
Displacement power fac-
tor
cos
DPF
-
cos 𝜑 = 𝐷𝑃𝐹 = cos(𝜑
𝑈
1
− 𝜑
𝐼
1
)
where
U1
is an absolute angle of the fundamental com-
ponent of voltage
U
A-N
I1
is an absolute angle of the fundamental component
of current
I
A
Tangent
tan
-
𝑡𝑎𝑛𝜑 =
𝑄
𝑃
where:
Q = Q
B
when Budeanu method was chosen,
Q = Q
1
when IEEE 1459 method was chosen,
Harmonic components of
voltage and current
U
hx
I
hx
V
A
method of harmonic subgroups according to IEC 61000-
4-7
x (harmonic) = 1..40
Total Harmonic Distortion
for voltage, referred to
the fundamental compo-
nent
THDU
F
-
𝑇𝐻𝐷𝑈
𝐹
=
√∑
𝑈
ℎ
2
40
ℎ=2
𝑈
1
× 100%
where
U
h
is
h
-th harmonic of voltage
U
A-N
U
1
is fundamental component of voltage
U
A-N
Total Harmonic Distortion
for voltage, referred to
RMS
THDU
R
-
𝑇𝐻𝐷𝑈
𝑅
=
√∑
𝑈
ℎ
2
40
ℎ=2
𝑈
𝐴𝑅𝑀𝑆
× 100%
where
U
h
is
h
-th harmonic of voltage
U
A-N
Total Harmonic Distortion
for current, referred to
the fundamental compo-
nent
THDI
F
-
𝑇𝐻𝐷𝐼
𝐹
=
√∑
𝐼
ℎ
2
40
ℎ=2
𝐼
1
× 100%
where
I
h
is
h
-th harmonic of current
I
A
I
1
is fundamental component of current
I
A
Total Harmonic Distortion
for current, referred to
RMS
THDI
R
-
𝑇𝐻𝐷𝐼
𝑅
=
√∑
𝐼
ℎ
2
40
ℎ=2
𝐼
𝐴𝑅𝑀𝑆
× 100%
where
I
h
is
h
-th harmonic of current
I
A
Voltage crest factor
CFU
-
𝐶𝐹𝑈 =
𝑚𝑎𝑥|𝑈
𝑖
|
𝑈
𝐴𝑅𝑀𝑆
𝑚𝑎𝑥|𝑈
𝑖
|
Where the operator expresses the highest abso-
lute value of voltage
U
A-N
samples
i
= 2048 for 50 Hz and 60 Hz
Current crest factor
CFI
-
𝐶𝐹𝐼 =
𝑚𝑎𝑥|𝐼
𝑖
|
𝐼
𝐴𝑅𝑀𝑆
𝑚𝑎𝑥|𝐼
𝑖
|
Where the operator expresses the highest abso-
lute value of current
I
A
samples
i
= 2048 for 50 Hz and 60 Hz
Short-term flicker
P
st
-
calculated according to IEC 61000-4-15
Long-term flicker
P
lt
-
𝑃
𝐿𝑇
=
1
3
√∑(𝑃
𝑆𝑇𝑖
)
3
12
𝑖=1
where P
STi
is subsequent i-th indicator of short-term
flicker
Summary of Contents for PQM-700
Page 85: ...85 Notes...
