App-5
IM WT310E-01EN
Appendix
App
Harmonic distortion factor
of voltage
Uhdf( ) [%]
Total harmonic voltage
distortion
Uthd [%]
Measurement Function
Methods of Computation and Determination
(Table 2/2)
U(k)
U(Total)*
U(k)
U(1)
• 100 • 100
P(k)
P(Total)*
P(k)
P(1)
• 100 • 100
I(k)
I(Total)*
I(k)
I(1)
• 100
• 100
Harmonic distortion factor
of active power
Phdf( ) [%]
Harmonic distortion factor
of current
Ihdf( ) [%]
k = 2
max
U(k)
2
U(Total)*
• 100
k = 2
max
U(k)
2
U(1)
• 100
Total harmonic current
distortion
Ithd [%]
k = 2
max
I(k)
2
I(Total)*
• 100
k = 2
max
I(k)
2
I(1)
• 100
When the Denominator of the
THD Equation Is the Total Value (CSA)
When the Denominator of the
THD Equation Is the Fundamental Wave (IEC)
*
U(k)
2
k = 1
max
U(Total) =
I(k)
2
P(k)
k = 1
max
I(Total) =,
k = 1
max
P(Total) =,
Note
• kdenotesaharmonicorder.
• Theupperlimitofmeasuredharmonicorderisdenotedbymax.maxiseitheranautomaticallydetermined
value or the specified maximum measured harmonic order, whichever is smaller.
Appendix 1 Symbols and Determination of Measurement Functions