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Appendix 1 Symbols and Determination of Measurement Functions
Measurement Functions Used in Harmonic Measurement
Measurement Functions
Used in Harmonic
Measurement
Voltage U( ) [V]
Current I( ) (A)
Active power P( ) [W]
Apparent power S( ) [VA]
(TYPE3)*
Reactive power Q( ) [var]
(TYPE3)*
Power factor ( )
Phase difference ( ) [°]
Phase difference with U(1)
U(
) [°]
Phase difference with I(1)
I(
) [°]
* For details about the S and Q formula type settings, see section 5.4.
App-4
Methods of Computation and Determination
Numbers and Characters in the Parentheses
dc
(when k = 0)
U(dc) =U
(0)
r
I(dc) = I
(0)
r
P(dc) = U
(0)
I
(0)
r
•
r
S(dc) = P(dc)
Q(dc) = 0
P(dc)
(dc) =
S(dc)
—
—
—
Note
•
k denotes a harmonic order, r denotes the real part, and j denotes the imaginary part.
•
U(k), Ur(k), Uj(k), I(k), Ir(k), and Ij(k) are expressed using rms values.
•
The minimum harmonic order is denoted by min. min can be set to either 0 (the dc
component) or 1 (the fundamental signal). For details, see section 6.4.
•
The upper limit of harmonic analysis is denoted by max. max is determined automatically
according to the PLL source frequency. It can go up to the 50
k
(when k = 1 to max)
2
2
U(k) =
U
(k)
+
U
(k)
r
j
2
2
I(k) =
I
(k)
+
I
(k)
r
j
P(k) =
U
(k)
I
(k) +
U
(k)
I
r
•
r
j
•
2
2
S(k) =
P(k)
+ Q(k)
Q(k) =
U
(k)
I
(k) –
U
(k)
I
r
•
j
j
•
P(k)
(k) =
S(k)
Q(k)
–1
(k) = tan
P(k)
U(k) = The phase difference
between U(k) and U(1)
I(k) = The phase difference
between I(k) and I(1)
(Table 1/2)
Total Value (Total)
(No parentheses)
max
U
U =
(k)
k = min
max
I
(k)
I =
k = min
max
P
(k)
(k)
P =
j
k = min
2
S =
P
+ Q
max
Q
(k)
Q =
(k)
r
k = min
P
=
S
( )
P
–1
= tan
S
—
—
(Continues on next page)
th
harmonic order.
IM 760201-01E
2
2
2
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