IEC IECTR 61850-90-21 Edition 1.02025-02 TECHNICAL REPORT INTERNATIONAL ELECTROTECHNICAL COMMISSION ICS 33.200 ISBN 978-2-8327-0163-8 Warning! Make sure that you obtained this publication from an authorized distributor. ? Registered trademark of the International Electrotechnical Commission - 2 - IECTR61850-90-21:2025@IEC2025 FOREWORD 5 INTRODUCTION. 1 Scope.. :8 1.1 Scope of work.. ..8 1.2 Published versions of the standard and related namespace names .... ..8 1.3 Namespace name and version ....... 1.4 Published versions of the standard and related namespace names.. 1.5 Code Component distribution... .9 2 Normative references .10 3 Terms and definitions ... 4 Types of travelling wave fault location . .10 5 Requirements and use cases. .11 5.1 General...... ..11 5.2 Use case1: Single-ended fault location (Type A).... 5.2.1 Use case 1A: Single-ended fault location (Type A) - phase segregated......12 5.2.2 Use case 1B: Single-ended fault location (Type A)-3-phase lines with modes at different speeds..... 5.3 Use case 2: Double-ended fault location (Type D) through communications betweentwo devices.... ....23 5.3.1 Description of the use case ...23 5.3.2 ...25 Diagram of the use case 5.3.3 Technical details. .26 5.3.4 Step by step analysis of the use case .27 5.3.5 Information exchanged .29 5.4 Usecase3:Double-ended fault location(Type D)through communications with a master station... 5.4.1 Description of the use case 5.4.2 Diagram of the use case. ..31 ...32 5.4.3 Technical details.. 5.4.4 Stepbystepanalysisof theusecase ..33 5.4.5 Information exchanged.. ..35 5.5 Use case 4: Wide area fault location (Type W) .35 5.5.1 Description of the use case .. ..35 5.5.2 Diagram of the use case.. 5.5.3 5.5.4 Stepbystepanalysisof theusecase. 5.5.5 Information exchanged ...... 5.6 Use case 5: Pulse radar echo method (Type C and Type FMCW) 5.6.1 Description of the use case .... ..43 5.6.2 Diagram of the use case..... ...45 5.6.3 Technical details...... .47 5.6.4 Step by step analysis of the use case...... ..48 5.6.5 Information exchanged. 5.7 Use case 6: Integration with other fault location and disturbance recording functions in a substation ..... ...50 5.7.1 Description of the use case .. ..50 5.7.2 Diagram of the use case... .51 - 3 - IECTR61850-90-21:2025IEC2025 5.7.3 Technical details... 5.7.4 Step by step analysis of the use case. 5.7.5 Information exchanged... ...55 5.8 Use case 7: Testing and calibration .. ..55 5.8.1 Use case 7a: Wave velocity calibration... ..55 5.8.2 Use case 7b: Simulation testing by remote commands.. ..60 5.8.3 Use case 7c:Calibrationforthe pulseradarechomethod .64 5.9 Use case 8: Fault location for hybrid lines. .68 6 Information models .69 6.1.1 Mapping of the requirements of use case 1. .69 6.1.2 Mapping of the requirements of use case 2. .70 6.1.3 Mapping of the requirements of use case 3.. 71 6.1.4 Mapping of the requirements of use case 4.. 6.1.5 Mapping of the requirements of use case 5.. 6.1.6 Mapping of the requirements of use case 6.. ..74 6.1.7 Mapping of the requirements of use case 7a.. 6.1.8 Mapping of the requirements of use case 7b. .76 6.1.9 Mapping of the requirements of use case 7c. .77 Logical node classes and data objects modelling... ..78 7.1 General... 7.2 Abbreviated terms used in data object names .78 7.3 Logical node classes. .78 7.3.1 General .78 7.3.2 Classes list .79 7.3.3 Logical nodes for protection related functions of 90-21 (LNGroupR) ..79 7.3.4 Logical nodes for further power system equipment of 90-21 (LNGroupZ).....86 7.4 Dataobjectnamesemantics 8 System configuration .. 8.1 General. .92 8.2 Double-circuit line. 8.3 Topology for single line with aerial mode and zero mode . AnnexA(normative)Conditionsforelementpresence. ..95 AnnexB(informative)Explanation of percentage full scale .97 Bibliography... ..98 Figure1-Wide-areatravellingwavefault locationsystem Figure 2-Class diagram LogicalNodes_90_21:LogicalNodes_90_21 ..79 Figure3-Class diagram LNGroupR:LNGroupRext. ..80 Figure4-Clas