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Introduction
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Operating instructions RHF
ELTROPLAN
-
REVCON
Elektrotechnische Anlagen GmbH
IEEE519 is a system standard that aims the control of the voltage distortion at the
PCC to a THD of 5% and limits the maximum individual frequency voltage har-
monic to 3%. The development of harmonic current limits aims the limitation of
harmonic injection from individual customers so they will not cause unacceptable
voltage distortion levels and the limitation of the overall harmonic distortion of the
system voltage supplied by the utility.
The current distortion limits are given in Table 10.3 in the standard and depend on
the ratio ISC/IL where ISC is the short circuit current at the utility PCC and IL is the
maximum demand load current.
The limits are given for individual harmonics up to the 35th and total demand dis-
tortion (TDD). Please note that these limits apply at the PCC to the utility. While
requiring individual loads to comply with these limits also ensures the compliance
at the PCC, this is rarely the most economic solution, being unnecessarily ex-
pensive. The most effective way to meet the harmonic distortion requirements is
to mitigate at the individual loads and measure at the PCC.
If in a specific application it is required that the individual drive should comply with
the IEEE519 current distortion limits, an AHF can be employed to meet these lim-
its.
G5/4
,
Engineering recommendation, planning levels for harmonic voltage
distortion and the connection of nonlinear equipment to transmission sys-
tems and distribution networks in the United Kingdom:
G5/4 sets the Planning levels for harmonic voltage distortion to be used in the pro-
cess of connecting non-linear equipment. A process for establishing individual cus-
tomer emission-limits based on these planning levels is described.
G5/4 is a system level standard. For 400V the voltage THD planning level is 5%
at the PCC. Limits for odd and even harmonics in 400V systems are given in Ta-
ble 2 in the standard. An assessment procedure for the connection of non-linear
equipment is described. The procedure follows three stages, aiming to balance
the level of detail required by the assessment process with the degree of risk that
the connection of particular equipment will result in unacceptable voltage har-
monic distortion
.
A RHF-filter should be employed to meet the requirements of G5/4.