SIST-TS CLC/TS 50654-2:2020

HVDC Grid Systems and connected Converter Stations - Guideline and Parameter Lists for Functional Specifications - Part 2: Parameter Lists

This document in conjunction with CLC/TS 50654-1: 2018-03 Guideline for Functional Specifications describes specific functional requirements for HVDC Grid Systems in Europe. The terminology “HVDC Grid Systems” is used here describing HVDC systems for power transmission having more than two converter stations connected to a common DC circuit.
While this document focuses on requirements, that are specific for HVDC Grid Systems, some requirements are considered applicable to all HVDC systems in general, i.e. including point-to-point HVDC systems. Existing IEC, Cigré or other documents relevant have been used for reference as far as possible.
Corresponding to electric power transmission applications, this document is applicable to high voltage systems, i.e. only nominal DC voltages equal or higher than 50 kV with respect to earth are considered in this document.

Hochspannungsgleichstrom-Netzsysteme - Leitfaden und Parameter-Listen für funktionale Spezifikationen - Teil 2: Parameter-Listen

Réseaux CCHT et stations de conversion connectées - Lignes directrices et listes de paramètres pour les spécifications fonctionnelles - Partie 2: Listes de paramètres

Sistemi visokonapetostnega enosmernega omrežja in priključene pretvorniške postaje - Smernice in seznam parametrov za funkcijsko specifikacijo - 2. del: Seznam parametrov

General Information

• Status: Published
• Publication Date: 19-Jul-2020
• ICS: 29.240.01 - Power transmission and distribution networks in general
• Technical Committee: NTF - Electricity energy supply systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 07-Jul-2020
• Due Date: 11-Sep-2020
• Completion Date: 20-Jul-2020
• Ref Project: CLC/TS 50654-2:2020 - HVDC Grid Systems and connected Converter Stations - Guideline and Parameter Lists for Functional Specifications - Part 2: Parameter Lists

RELATIONS

• Replaces: SIST-TS CLC/TS 50654-2:2018 - HVDC Grid Systems and connected Converter Stations - Guideline and Parameter Lists for Functional Specifications - Part 2: Parameter Lists
• Effective Date: 01-Sep-2020

Standards Content (sample)

SLOVENSKI STANDARD
SIST-TS CLC/TS 50654-2:2020
01-september-2020
Nadomešča:
SIST-TS CLC/TS 50654-2:2018
Sistemi visokonapetostnega enosmernega omrežja in priključene pretvorniške
postaje - Smernice in seznam parametrov za funkcijsko specifikacijo - 2. del:
Seznam parametrov

HVDC Grid Systems and connected Converter Stations - Guideline and Parameter Lists

for Functional Specifications - Part 2: Parameter Lists
Hochspannungsgleichstrom-Netzsysteme - Leitfaden und Parameter-Listen für
funktionale Spezifikationen - Teil 2: Parameter-Listen

Réseaux CCHT et stations de conversion connectées - Lignes directrices et listes de

paramètres pour les spécifications fonctionnelles - Partie 2: Listes de paramètres

Ta slovenski standard je istoveten z: CLC/TS 50654-2:2020
ICS:
29.240.01 Omrežja za prenos in Power transmission and
distribucijo električne energije distribution networks in
na splošno general
SIST-TS CLC/TS 50654-2:2020 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS CLC/TS 50654-2:2020
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SIST-TS CLC/TS 50654-2:2020
TECHNICAL SPECIFICATION CLC/TS 50654-2
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
June 2020
ICS 29.240.01 Supersedes CLC/TS 50654-2:2018
English Version
HVDC Grid Systems and connected Converter Stations -
Guideline and Parameter Lists for Functional Specifications -
Part 2: Parameter Lists

Réseaux CCHT et stations de conversion connectées - Hochspannungsgleichstrom-Netzsysteme - Leitfaden und

Lignes directrices et listes de paramètres pour les Parameter-Listen für funktionale Spezifikationen - Teil 2:

spécifications fonctionnelles - Partie 2: Listes de Parameter-Listen
paramètres
This Technical Specification was approved by CENELEC on 2020-04-13.

CENELEC members are required to announce the existence of this TS in the same way as for an EN and to make the TS available promptly

at national level in an appropriate form. It is permissible to keep conflicting national standards in force.

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,

Turkey and the United Kingdom.
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

© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. CLC/TS 50654-2:2020 E
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Contents Page

European foreword ........................................................................................................6

Introduction ...................................................................................................................7

1 Scope .................................................................................................................8

1.1 General ..............................................................................................................8

1.2 About the present release...................................................................................8

2 Normative references .........................................................................................9

3 Terms, definitions and abbreviations ................................................................10

3.1 Terms and definitions .......................................................................................10

3.2 Abbreviations ....................................................................................................12

4 Coordination of HVDC Grid System and AC Systems ...................................... 13

4.1 General ............................................................................................................13

4.2 Purpose of the HVDC Grid System and Power Network Diagram ..................... 13

4.3 AC/DC Power Flow Optimisation ......................................................................13

4.4 Converter Operational Functions ......................................................................17

4.4.1 Basic Operation Functions – Converter Normal Operation State ................... 17

4.4.2 Basic Operation Functions – Converter Abnormal Operation State ................ 18

4.4.3 Ancillary Services ..........................................................................................21

5 HVDC Grid System Characteristics ..................................................................25

5.1 HVDC Circuit Topologies ..................................................................................25

5.1.1 Availability and Reliability ...............................................................................25

5.1.2 Basic Characteristics and Nomenclature ....................................................... 26

5.1.3 Attributes of HVDC Grid Systems or HVDC Grid Sub-Systems...................... 26

5.1.4 Attributes of a Station ....................................................................................26

5.2 Connection Modes............................................................................................ 27

5.3 Grid Operating States .......................................................................................27

5.3.1 General ..........................................................................................................27

5.3.2 Normal State ..................................................................................................27

5.3.3 Alert State ......................................................................................................27

5.3.4 Emergency State ...........................................................................................28

5.3.5 Blackout State ...............................................................................................28

5.3.6 Restoration ....................................................................................................28

5.4 DC Voltages .....................................................................................................28

5.4.1 General ..........................................................................................................28

5.4.2 Nominal DC System Voltage .........................................................................29

5.4.3 Steady-State DC Voltage ...............................................................................30

5.4.4 Temporary DC Voltage ..................................................................................30

5.4.5 Neutral Bus Voltages .....................................................................................31

5.5 Insulation Coordination .....................................................................................31

5.6 Short-Circuit Characteristics .............................................................................31

5.6.1 Calculation of Short-Circuit Currents in HVDC Grid Systems ......................... 31

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5.6.2 Short-Circuit Current Design Requirements ................................................... 33

5.7 Steady-State Voltage and Current Distortions .................................................. 33

5.7.1 Voltage and Current Distortion Limits.............................................................33

5.7.2 Frequency Dependent DC System Impedance .............................................. 34

5.8 DC System Restoration ....................................................................................34

5.8.1 General ..........................................................................................................34

5.8.2 Post DC Fault Recovery ................................................................................34

5.8.3 Restoration from Blackout ..............................................................................34

6 HVDC Grid System Control ..............................................................................35

6.1 Closed-Loop Control Functions ........................................................................35

6.1.1 General ..........................................................................................................35

6.1.2 Core Control Functions ..................................................................................35

6.1.3 Coordinating Control Functions ......................................................................35

6.2 Controller Hierarchy .......................................................................................... 35

6.2.1 General ..........................................................................................................35

6.2.2 Internal Converter Control ..............................................................................35

6.2.3 DC Node Voltage Control ..............................................................................35

6.2.4 Coordinated HVDC Grid System Control ....................................................... 35

6.2.5 AC/DC Grid Control .......................................................................................37

6.3 Propagation of Information ...............................................................................38

6.4 Open-Loop Controls .........................................................................................41

6.4.1 Coordination of Connection Modes between Stations and their PoC-DCs ..... 41

6.4.2 Operating Sequences for HVDC Grid System Installations ............................ 41

6.4.3 Post DC Fault Recovery ................................................................................43

7 HVDC Grid System Protection ..........................................................................43

7.1 General ............................................................................................................43

7.2 DC Fault Separation .........................................................................................43

7.3 Protection System Related Installations and Equipment ................................... 43

7.3.1 AC/DC Converter Station ...............................................................................43

7.3.2 HVDC Grid System Topology and Equipment ................................................ 43

7.4 HVDC Grid System Protection Zones ...............................................................43

7.4.1 General ..........................................................................................................43

7.4.2 Permanent Stop P .........................................................................................45

7.4.3 Permanent Stop PQ .......................................................................................46

7.4.4 Temporary Stop P..........................................................................................46

7.4.5 Temporary Stop PQ .......................................................................................46

7.4.6 Continued Operation ......................................................................................46

7.4.7 Example of a Protection Zone Matrix .............................................................46

7.5 DC Protection ...................................................................................................46

7.5.1 General ..........................................................................................................46

7.5.2 DC Converter Protections ..............................................................................47

7.5.3 HVDC Grid System Protections .....................................................................47

7.5.4 DC Grid Protection Communication ...............................................................47

8 AC/DC Converter Stations ................................................................................47

8.1 Introduction ......................................................................................................47

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8.2 AC/DC Converter Station Types .......................................................................47

8.3 Overall Requirements .......................................................................................47

8.3.1 Robustness of AC/DC Converter Stations ..................................................... 47

8.3.2 Availability and Reliability ...............................................................................47

8.3.3 Active Power Reversal ...................................................................................48

8.4 Main Circuit Design .......................................................................................... 48

8.4.1 General Characteristics .................................................................................48

8.4.2 DC Side .........................................................................................................49

8.4.3 AC Side .........................................................................................................54

8.5 Controls ............................................................................................................54

8.5.1 General ..........................................................................................................54

8.5.2 Automated vs. Manual Operation ................................................................... 54

8.5.3 Control Modes & Support of Coordination ...................................................... 55

8.5.4 Limitation Strategies ......................................................................................56

8.5.5 Operating Sequences for AC/DC Converter Station ....................................... 56

8.5.6 Dynamic Behaviour ........................................................................................56

8.6 Protection .........................................................................................................57

8.6.1 General ..........................................................................................................57

8.6.2 Configuration Requirements ..........................................................................57

8.6.3 Function Requirements ..................................................................................57

8.6.4 DC Grid Interface ...........................................................................................57

8.6.5 Fault Separation Strategy for Faults inside the AC/DC Converter Station ...... 57

8.6.6 Coordination of the DC Protection with the HVDC Grid System ..................... 57

8.6.7 Example for Coordination of the DC Protection with the HVDC Grid System . 57

9 HVDC Grid System Installations .......................................................................57

9.1 General ............................................................................................................57

9.2 DC Switching Station ........................................................................................58

9.2.1 Overall Requirements ....................................................................................58

9.2.2 Main Circuit Design ........................................................................................58

9.2.3 Controls .........................................................................................................64

9.2.4 Protection ......................................................................................................68

10 Models and Validation ......................................................................................69

10.1 Introduction ......................................................................................................69

10.2 HVDC Grid System Studies ..............................................................................69

10.2.1 Type of Studies ..............................................................................................69

10.2.2 Tools and Methods ........................................................................................69

10.3 Model General Specifications ...........................................................................69

10.3.1 Model Capability ............................................................................................ 69

10.3.2 Model Format and Data Type ........................................................................69

10.3.3 Model Aggregation.........................................................................................69

10.4 Model Specific Recommendations ....................................................................70

10.4.1 Load Flow Models..........................................................................................70

10.4.2 Short-Circuit Models ......................................................................................71

10.4.3 Protection System Models .............................................................................71

10.4.4 Insulation Coordination Related Models ......................................................... 71

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10.4.5 Electromechanical Transient Models .............................................................71

10.4.6 Electromagnetic Transient Models ................................................................. 72

10.4.7 Power Quality Models ....................................................................................78

10.5 Model Validation ...............................................................................................78

10.6 Compliance Simulation .....................................................................................79

10.7 Outputs/Results ................................................................................................79

10.7.1 Model Data ....................................................................................................79

10.7.2 Model Documentation ....................................................................................79

10.7.3 Model Example .............................................................................................. 79

10.7.4 Model Compliance Documentation ................................................................80

10.7.5 Model Validation Documentation – Model Final Version ................................ 80

10.7.6 Model Guarantee ...........................................................................................80

11 HVDC Grid System Integration Tests ...............................................................80

11.1 Off-Site Testing of the HVDC Control and Protection System ........................... 80

11.2 Dynamic Performance Study/Tests (DPS) Performed with Offline Models ........ 80

11.2.1 DPS Simulations in a Multi-Vendor Environment ........................................... 80

11.2.2 DPS Simulations Scenarios ...........................................................................80

11.3 Factory Tests ....................................................................................................81

11.3.1 General ..........................................................................................................81

11.3.2 Factory Test Scenarios ..................................................................................81

11.3.3 Factory Tests when Existing System C&P Replicas are Available ................. 81

11.3.4 Factory Tests when Existing System C&P Replicas are not Available ........... 81

11.4 On Site Testing ................................................................................................. 82

Bibliography ................................................................................................................83

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European foreword

This document (CLC/TS 50654-2:2020) has been prepared by CLC/TC8X “System aspects of electrical

energy supply”.
This document supersedes CLC/TS 50654-2:2018.

CLC/TS 50654-2:2020 includes the following significant technical changes with respect to CLC/TS 50654-

2:2018:
— new content concerning AC/DC converter stations;

— new content concerning HVDC Grid System installations, including DC switching stations;

— new content concerning HVDC Grid System integration tests.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

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Introduction

HVDC Grid Systems are a new field of technology. There are very few systems with a small number of

converter stations in operation; some more are in execution or in detailed planning.

The Guidelines and Parameter Lists to Functional Specifications are presented featuring planning,

specification and execution of multi-vendor HVDC Grid Systems in Europe. Being elaborated by a team of

experts from leading manufacturers of HVDC technology, Transmission System Operators (TSO's),

Academia and Institutions in Europe, the present document provides a commonly agreed basis for an open

market of compatible equipment and solutions for HVDC Grid Systems. Executing such systems and

gaining operational experience is seen an important prerequisite for developing corresponding technical

standards in the future.

By elaborating this document, special care has been taken to as far as possible describe the requirements

in a technologically independent way. In order to achieve that, a function of interest is described by a

comprehensive set of parameters. The parameters are selected based on a systematic analysis of physical

phenomena relevant to achieve the requested functionality. The physical phenomena are categorized in

order to show the mutual dependence of the individual parameters and ensure completeness of the physical

aspects to be considered. Based on a clearly defined common language describing the functionalities

requested, existing technologies can be applied, or new dedicated technical solutions can be developed.

Reflecting the early stage of technology, these Guidelines and Parameter Lists to Functional Specifications

need comprehensive explanations and background information for the technical parameters. This dual

character of the content will be represented by two corresponding parts:

• Part I “Guidelines” containing the explanations and the background information in context with the

Parameter Lists.

• Part II “Parameter Lists” containing the essential lists of parameters and values describing

properties of the AC respectively DC system (operating conditions) and parameters describing the

performance of the newly installed component (performance requirements).
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1 Scope
1.1 General

These Guidelines and Parameter Lists to Functional Specifications describe specific functional

requirements for HVDC Grid Systems. The terminology “HVDC Grid Systems” is used here describing

HVDC systems for power transmission having more than two converter stations connected to a common

DC circuit.

While this document focuses on requirements, that are specific for HVDC Grid Systems, some requirements

are considered applicable to all HVDC systems in general, i.e. including point-to-point HVDC systems.

Existing IEC, Cigré or other documents relevant have been used for reference as far as possible.

Corresponding to electric power transmission applications, this document is applicable to high voltage

systems, i.e. only nominal DC voltages equal or higher than 50 kV with respect to earth are considered in

this document.

NOTE While the physical principles of DC networks are basically voltage independent, the technical options for

designing equipment get much wider with lower DC voltage levels, e.g. in case of converters or switchgear.

Both parts have the same outline and headlines to aid the reader.
1.2 About the present release

The present release of the Guidelines and Parameter Lists for Functional Specifications describes technical

guidelines and specifications for HVDC Grid Systems which are characterized by having exactly one single

connection between two converter stations, often referred to as radial systems. When developing the

requirements for radial systems, care is taken not to build up potential showstoppers for meshed systems.

Meshed HVDC Grid Systems can be included into this specification at a later point in time.

The Guidelines and Parameter List to the Functional Specification of HVDC Grid Systems cover technical

aspects of:
• coordination of HVDC grid and AC systems
• HVDC Grid System characteristics
• HVDC Grid System control
• HVDC Grid System protection
• AC/DC converter stations
• HVDC Grid System installations, including DC switching stations
• models and validation
• HVDC Grid System integration tests
Beyond the present scope, the following content is proposed for future work:
• transmission lines and transition stations
• DC/DC converter stations
• DC line power flow controllers
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2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes

requirements of this document. For dated references, only the edition cited applies. For undated references,

the latest edition of the referenced document (including any amendments) applies.

EN 61660-1:1997, Short-circuit currents in d.c. auxiliary installations in power plants and substations - Part

1: Calculation of short-circuit currents

IEC/TR 60919-1:2010 , Performance of high-voltage direct current (HVDC) systems with line-commutated

converters – Part 1: Steady-state conditions

IEC 62747:2014 , Terminology for voltage-sourced converters (VSC) for high-voltage direct current

(HVDC) systems
IEV 351-45-27, International electrotechnical vocabulary, control technology
As impacted by IEC/TR 60919-1:2010/A1:2013, IEC/TR 60919-1:2010/A2:2017.
As impacted by IEC 62747:2014/A1:2019.
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3 Terms, definitions and abbreviations
3.1 Terms and definitions

For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain

terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
AC/DC converter unit

indivisible operative unit comprising all equipment between the point of connection on the AC side and the

point of connection on the DC side, essentially one or more converters, together with converter

transformers, control equipment, essential protective and switching devices and auxiliaries, if any, used for

conversion

[SOURCE: EN 62747:2014 , modified – The definition was neutralised with respect to technology (not only

VSC converters) and uses the terms PoC as defined in the present document]
3.1.2
AC/DC converter station

part of an HVDC system which consists of one or more AC/DC converter units including DC switchgear,

DC fault current controlling devices, if any, installed in a single location together with buildings, reactors,

filters, reactive power supply, control, monitoring, protective, measuring and auxiliary equipment

[SOURCE: EN 62747:2014 , modified – The definition was made specific with respect to AC/DC converter

units, differentiating from DC/DC converter units. Furthermore, only the term AC/DC converter station is

used in the present document]
3.1.3
Point of connection-DC
PoC-DC
electrical interface point at DC voltage as shown in Figure 1
3.1.4
Point of connection-AC
PoC-AC
electrical interface point at AC voltage as shown in Figure 1

Figure 1 — Definition of the Point of Connection-AC and the Point of Connection-DC at an AC/DC

converter station
3.1.5
DC/DC converter unit

indivisible operative unit comprising all equipment between the points of connection to the HVDC Grid

System, essentially one or more converters, together with converter transformers, if any, control equipment,

essential protective and switching devices and auxiliaries, if any, used for conversion

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3.1.6
DC/DC co
...