EN 50549-2:2019/prA1:2023

SLOVENSKI STANDARD
SIST EN 50549-2:2019/oprA1:2023
01-junij-2023
Zahteve za vzporedno vezavo generatorskih postrojev z razdelilnim omrežjem - 2.
del: Vezava s srednjenapetostnim razdelilnim omrežjem - Generatorski postroji do
vključno tipa B - Dopolnilo A1
Requirements for generating plants to be connected in parallel with distribution networks
- Part 2: Connection to a MV distribution network - Generating plants up to and including
Type B
Ta slovenski standard je istoveten z: EN 50549-2:2019/prA1:2023
ICS:
29.160.20 Generatorji Generators
29.240.01 Omrežja za prenos in Power transmission and
distribucijo električne energije distribution networks in
na splošno general
SIST EN 50549-2:2019/oprA1:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50549-2:2019/oprA1:2023

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SIST EN 50549-2:2019/oprA1:2023
EUROPEAN STANDARD DRAFT
EN 50549-2:2019
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
May 2023
ICS 29.160.20 -
English Version
Requirements for generating plants to be connected in parallel
with distribution networks - Part 2: Connection to a MV
distribution network - Generating plants up to and including
Type B
To be completed To be completed
This draft amendment prA1, if approved, will modify the European Standard EN 50549-2:2019; it is submitted to CENELEC members for
enquiry.
Deadline for CENELEC: 2023-08-11.
It has been drawn up by CLC/TC 8X.
If this draft becomes an amendment, CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this amendment the status of a national standard without any alteration.
This draft amendment was established by CENELEC in three official versions (English, French, German).
A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to
the CEN-CENELEC Management Centre has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Project: 73644 Ref. No. EN 50549-2:2019/prA1:2023 E

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SIST EN 50549-2:2019/oprA1:2023
EN 50549-2:2019/prA1:2023 (E)
9 Contents Page
10 European foreword . 3
11 1 Modification to Introduction . 4
12 2 Modification to Clause 2, “Normative references” . 4
13 3 Modification to Clause 3, “Terms and definitions” . 4
14 4 Modification to Clause 4, “Requirements on generating plants” . 5
15 5 Modification to Annex C, “Parameter Table” . 9
16 6 Modification to Annex D, “List of national requirements applicable for generating plants”
17 .10
18 7 Modification to Annex F, “Examples of protection strategies” .10
2

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SIST EN 50549-2:2019/oprA1:2023
EN 50549-2:2019/prA1:2023 (E)
19 European foreword
20 This document EN 50549-2:2019/prA1:2023 has been prepared by TC 8X “System aspects of electrical energy
21 supply”.
22 This document is currently submitted to the Enquiry.
23 The following dates are proposed:
• latest date by which the existence of this (doa) dor + 6 months
document has to be announced at national
level
• latest date by which this document has to be (dop) dor + 12 months
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) dor + 36 months
conflicting with this document have to be (to be confirmed or
withdrawn modified when voting)
24 This document will amend EN 50549-2:2019.
25 This amendment includes the following significant technical changes:
26 — Introduction of a phase jump immunity requirement.
27 — Harmonizing the ROCOF immunity requirement for synchronous and non-synchronous generating
28 technology.
29 — Modifying FRT for type A from recommendation to requirement.
30 — Providing additional detail for EESS in case of overfrequency.
3

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SIST EN 50549-2:2019/oprA1:2023
EN 50549-2:2019/prA1:2023 (E)
31 1 Modification to Introduction
32 Replace item 8. with the following:
33 “8. Implementation of UVRT and LFSM-U to avoid legal conflict with RfG
34 Under Voltage Ride Through (UVRT) requirements are defined in RfG for modules type B, type C and type D.
35 There is no mentioning of this topic for type A modules.
36 Nevertheless, UVRT is seen as an important requirement in some member states even for small generation
37 modules like type A.
38 NOTE At the time of writing, LVRT requirements for type A modules have been implemented in the following countries:
39 Austria, Czech Republic, Germany, Portugal (for PGM of 15 kW and higher), Switzerland.
40 From a legal point of view there are two contradicting opinions on whether it is allowed or forbidden to require
41 UVRT for type A modules.
42 — Opinion 1: It can be required because the topic is not dealt with for type A modules.
43 — Option 2: It cannot be required because the topic UVRT is dealt within the RfG. Not mentioning UVRT for
44 type A in RfG therefore means that it cannot be required for type A modules.
45 TC8X WG03 adopts the view of ACER as expressed in “ACER Monitoring of the Implementation of the Grid
46 Connection Network Codes” 11 November 2021 Item 3.3.4 #D where it states the German UVRT requirement
47 for Type A as compliant with NC RfG.
48 This same explanation can be applied to the requirements regarding Limited Frequency Sensitive Mode -
49 Underfrequency (LFSM-U). In RfG, this LFSM-U is solely defined for type C and type D modules. In EN 50549,
50 LFSM-U is defined as a recommendation (should) for generating modules of type A and type B. The sole
51 exception is electrical energy storage systems having a requirement (shall). These systems are currently not
52 within the scope of the RfG.”
53 2 Modification to Clause 2, “Normative references”
54 Add the following reference:
55 EN 50549-10, Requirements for generating plants to be connected in parallel with distribution networks - Part
56 10: Tests for conformity assessment of generating units
57 Delete the reference EN 60255-127.
58 3 Modification to Clause 3, “Terms and definitions”
59 Add the following note to entry to 3.2.10:
60 “
61 Note 3 to entry: Electric vehicle charging stations intended to feed power back to the grid are considered a EESS while a
62 vehicle is connected “
63 Add the following note to entry to 3.2.11:
64 “
65 Note 2 to entry: Electric vehicle charging stations intended to feed power back to the grid are considered a EES while a
66 vehicle is connected”
67 Add the following term entries:
68 “
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SIST EN 50549-2:2019/oprA1:2023
EN 50549-2:2019/prA1:2023 (E)
69 3.4.9
70 phase
71 instantaneous phase
72 ϑ
73 argument of the cosine function in the representation of a sinusoidal quantity
74 Note 1 to entry: The term “instantaneous phase” is only used when the independent variable is time.
ˆ
75 Note 2 to entry: For the quantity a(t) = Atcos ω +ϑ , the phase is ωt+ϑ .
( )
0 0
76 [SOURCE: IEV 103-07-04]
77 3.4.10
78 instantaneous frequency:
79 first derivative of instantaneous phase
80 3.4.11
81 rate of change of frequency
82 ROCOF
83 first derivative of instantaneous frequency or second derivative of instantaneous phase
84 3.4.12
85 phase jump
86 abrupt change in the phase of the voltage of an AC electrical network
87 “
88 4 Modification to Clause 4, “Requirements on generating plants”
89 4.1 Modifcation to subclause 4.1, “General”
90 Add the following at the end of the subclause:
91 “EN 50549-10 provides technical guidance for tests on generating units and interface protection to evaluate
92 their electrical characteristics. EN 50549-10 shall be applied to evaluate the characteristics of generating units
93 and interface protection used in generating plants relating to the requirements of this Standard.Electrical
94 characteristics may alternatively be evaluated according to standards other than EN 50549-10, if the following
95 prerequisites are fulfilled:
96 — The alternative verification procedure covers all required technical aspects and characteristic quantities
97 stipulated in EN 50549-1 and EN 50549-2, respectively.
98 — The alternative verification procedure shall not be less stringent or technically less demanding than the
99 correspondent verification procedure in EN 50549-10.
100 — The alternative verification procedure leads to results of at least equivalent confidence level as
101 EN 50549-10.
102 — The equivalent or higher confidence level of the alternative verification procedure shall be confirmed by the
103 entity stating compliance based upon these tests
104 — The entity stating compliance based upon these tests shall have sufficient expertise in both EN 50549-10
105 and the applied standard.
106 NOTE This also applies for a partial application of another standard only for specific functions or operational
107 capabilities.”
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SIST EN 50549-2:2019/oprA1:2023
EN 50549-2:2019/prA1:2023 (E)
108 4.2 Modification to subclause 4.5, “Immunity to disturbances”
109 4.2.1 Modification to subclause 4.5.1, “General”
110 Add the following at the end of the subclause:
111 “The described immunity requirements are independent of the interface protection settings. Disconnection
112 settings of the interface protection relay always overrule technical capabilities. So, whether the generating plant
113 will stay connected or not will also depend upon those settings.”
114 4.2.2 Modification to subclause 4.5.2, “Rate of change of frequency (ROCOF) immunity”
115 Replace the content of the subclause with the following:
116 “ROCOF immunity of a power generating plant means that the generating modules in this plant stay connected
117 with the distribution network and are able to operate when the frequency on the distribution network changes
118 with a specified ROCOF. The generating units and all elements in the generating plant that might cause their
119 disconnection or impact their behaviour shall have the same level of immunity.
120 The generating modules in a generating plant shall have ROCOF immunity to ROCOF equal or exceeding the
121 value specified by the responsible party. If no ROCOF immunity value is specified, at least 2 Hz/s shall apply.
122 The ROCOF immunity is defined with a sliding measurement window of 500 ms.
123 NOTE 1 For control action based on frequency measurement shorter measurement periods are expected to be
124 necessary.
125 NOTE 2 For small isolated distribution networks (typically on islands) higher ROCOF immunity values might be required.
126 4.2.3 Modification to subclause 4.5.3, “Under-voltage ride through (UVRT)”
127 4.2.3.1 Modification to subclause 4.5.3.1, “General”
128 Replace the content of the subclause with the following:
129 “Generating modules shall comply with the requirements of 4.5.3.2 and 4.5.3.3.
130 Exempted from this requirement are small generating units below 50 kW of the following generation
131 technologies: CHP, fuel cell, rotating machinery, hydro.
132 NOTE 1 The power threshold of this exemption is expected to be reduced in future or the exception might be deleted
133 completely especially once the installed capacity becomes relevant for the grid stability.
134 The requirements apply to all kinds of faults (1ph, 2ph and 3ph).
135 NOTE 2 A more distinctive differentiation for 1ph, 2ph and 3ph faults is under consideration.
136 NOTE 3 The FRT curves in Figure 6, Figure 7 and Figure 8 describe the minimum requirements for continued connection
137 of the generating plant to the grid. They are not designed for parameterising the interface protection.”
138 4.2.4 Modification to subclause 4.5.4, “Over-voltage ride through (OVRT)”
139 Replace the content of the subclause with the following:
140 “Generating modules shall be capable of staying connected to the distribution network as long as the voltage at
141 the point of connection remains below the voltage-time curve of Figure 8.
142 The highest phase to neutral voltage or if no neutral is present the highest phase to phase voltage shall be
143 evaluated.
144 U disconnection is
In case of pre-fault voltages below nominal voltage and a voltage step of more than 2
...