YOKOGAWA WT500 User Manual page 306

14.4 Harmonic Measurement Functions (Measured
Items)
Measurement Functions Determined for Each Input Element
Item
Voltage (V)
Current (A)
Active power (W)
Apparent power (VA)
Reactive power (var)
Power factor
Phase difference (°)
Harmonic distortion factor (%) Uhdf(k): Ratio of harmonic voltage U(k) to U(1) or U(Total).
Total harmonic distortion (%) Uthd: Ratio of the total harmonic voltage to U(1) or U(Total).
1 Harmonic order k is an integer from 0 to the upper limit of harmonic analysis. The 0th order is the DC component. The upper
limit of harmonic analysis is either set to an automatically determined value or to the value that you set, whichever is smaller. It
can go up to the 50th harmonic order.
2 The total value is determined according to the equation in appendix 1 from the fundamental signal (1
nd
components (2 order to the upper limit of harmonic analysis). The DC component can also be included.
3 Total harmonic values are determined from all harmonic components (the 2
according to the equations in appendix 1.
Measurement Functions that Indicate Fundamental Voltage and Current Phase
Differences between and within Elements
Item
Phase difference U1-U2 (°)
Phase difference U1-U3 (°)
Phase difference U1-I1 (°)
Phase difference U1-I2 (°)
Phase difference U1-I3 (°)
Measurement Functions Determined for Each Wiring Unit (
Item
Voltage (V)
Current (A)
Active power (W)
Apparent power (VA)
Reactive power (var)
Power factor
1 The total value is determined according to the equation in appendix 1 from the fundamental signal (1
nd
components (2 order to the upper limit of harmonic analysis). The DC component can also be included.
IM 760201-01E
Symbols and Meanings
U(k): Rms voltage value of harmonic order k.
I(k): Rms current value of harmonic order k.
P(k): Active power of harmonic order k.
S(k): Apparent power of harmonic order k.
Q(k): Reactive power of harmonic order k.
λ
(k): Power factor of harmonic order k.
f
(k): Phase difference between the voltage and current of harmonic order k.
difference.
f
U(k): Phase difference between harmonic voltage U(k) and the fundamental signal U(1).
f I(k): Phase difference between harmonic current I(k) and the fundamental signal I(1).
Ihdf(k): Ratio of harmonic current I(k) to I(1) or I(Total).
Phdf(k): Ratio of harmonic active power P(k) to P(1) or P(Total).
Ithd: Ratio of the total harmonic current to I(1) or I(Total).
Pthd: Ratio of the total harmonic active power to P(1) or P(Total).
These measurement functions indicate the phase differences between the fundamental
voltage U(1) of the smallest numbered element in a wiring unit and the fundamental
voltages U(1) or currents I(1) of other elements. The following table indicates the
measurement functions for a wiring unit that combines elements 1, 2, and 3.
Symbols and Meanings
f
U1-U2: Phase difference between the fundamental voltage of element 1, which is expressed as
U1(1), and the fundamental voltage of element 2, which is expressed as U2(1).
f
U1-U3: Phase difference between U1(1) and the fundamental voltage of element 3, U3(1).
f
U1-I1: The phase difference between U1(1) and the fundamental current of element 1, I1(1).
f
U1-I2: The phase difference between U1(1) and the fundamental current of element 2, I2(1).
f U1-I3: The phase difference between U1(1) and the fundamental current of element 3, I3(1).
Symbols and Meanings
Σ
U (1): Rms voltage of harmonic order 1.
Σ
I (1): Rms current of harmonic order 1.
Σ
P (1): Active power of harmonic order 1.
Σ
S (1): Apparent power of harmonic order 1.
Σ
Q (1): Reactive power of harmonic order 1.
λΣ (1): Power factor of harmonic order 1.
1 2
U(Total): Rms voltage.
2
I(Total): Rms current.
P(Total): Active power. 2
S(Total): Total apparent power.
Q(Total): Total reactive power.
λ
(Total): Total power factor.
f
3
st
order) and all harmonic
nd
order to the upper limit of harmonic analysis)
Functions)
Σ
Σ
U (total value): Rms voltage.
Σ
I (total value): Rms current.
Σ
P (total value): Active power.
Σ
S (total value): Total apparent power.
Σ
Q (total value): Total reactive power.
λΣ (total value): Total power factor.
st
order) and all harmonic
1
2
3
2
2
2
4
: Total phase
5
6
7
8
9
10
11
12
13
1
1
14
1
1
1
1
App
Index
14-5