Thytronic Pro-N NVA100X-D

FUNCTION CHARACTERISTICS
47
NVA100X-D - Manual - 02 - 2016
Direct
Samples are processed by means DFT (Discrete Fourier Transform) algorithm and the phase and
amplitude of fundamental are computed:
Phase currents - side H and side L I
L1H
, I
L2H
, I
L3H
, I
L1L
, I
L2L
, I
L3L
Phase voltages U
L1
, U
L2
, U
L3
Residual current I
E1
and I
E2
Residual voltage U
E
Calculated
Frequency. The measure of period is taken preferably from phase voltage inputs
[1]
; when all volt-
age are missing the input current are employed.
Note 1 The frequency can also be measured on the three phase-to-phase voltages (calculated vectorially)
•
•
•
•
•
IL1.ai
(I
nH
, I
nL
)
i
L1H
, i
L2H
, i
L3H
i
L1L
, i
L2L
, i
L3L
DFT
≈
I
L1H
, I
L2H
, I
L3H
I
L1L
, I
L2L
, I
L3L
ACQUISITION
IL1.ai
(I
nH
, I
nL
)
i
L1H
, i
L2H
, i
L3H
i
L1L
, i
L2L
, i
L3L
DFT
≈
I
L1H
, I
L2H
, I
L3H
I
L1L
, I
L2L
, I
L3L
ACQUISITION
u
L1
, u
L2
, u
L3
DFT
U
L1
, U
L2
, U
L3
(E
n
)
UL1.ai
VTs
≈
ACQUISITION
u
L1
, u
L2
, u
L3
DFT
U
L1
, U
L2
, U
L3
(E
n
)
UL1.ai
VTs
≈
ACQUISITION
IE.ai
(I
En1
, I
En2
)
ACQUISITION
i
E1
, i
E2
DFT
≈
I
E1
, I
E2
IE.ai
(I
En1
, I
En2
)
ACQUISITION
i
E1
, i
E2
DFT
≈
I
E1
, I
E2
UE.ai
(U
En
)
(U
En
)
ACQUISITION
u
E
DFT (fundamental)
VT
≈
U
E
DFT (3rd harmonic)
U
E3H
UE.ai
(U
En
)
(U
En
)
ACQUISITION
u
E
DFT (fundamental)
VT
≈
U
E
DFT (3rd harmonic)
U
E3H
F.ai
(Hz)
(Hz)
u
L1
u
L2
U
L1
U
L2
ACQUISITION
≈
≈
u
L3
U
L3
I
L1H,
I
L1L
I
L2H,
I
L2L
I
L3H,
I
L3L
≈
u
L12
u
L23
u
L31
i
L1H,
i
L1L
i
L2H,
i
L2L
i
L3H,
i
L3L
≈
≈
≈
f
T
f
T
T
F.ai
(Hz)
(Hz)
u
L1
u
L2
U
L1
U
L2
ACQUISITION
≈
≈
u
L3
U
L3
I
L1H,
I
L1L
I
L2H,
I
L2L
I
L3H,
I
L3L
≈
u
L12
u
L23
u
L31
i
L1H,
i
L1L
i
L2H,
i
L2L
i
L3H,
i
L3L
≈
≈
≈
f
T
f
T