CONTENTS
FOREWORD 3
1Scope 5
2Normative references 5
3Terms and definitions 5
4Seismic qualification requirements 6
4.1General 6
4.2Qualification levels 6
5Test procedures for qualification 6
5.1General 6
5.2Mounting 7
5.3Measurements 7
5.4Frequency range 7
5.5Test severity 7
5.5.1General 7
5.5.2Parameters for time-history excitation 9
5.5.3Test directions 9
5.5.4Test sequence 9
6Qualification by combined test and numerical analysis 10
6.1General 10
6.2Dynamic and functional data 11
6.3Numerical analysis 11
6.3.1General 11
6.3.2Numerical analysis by the acceleration time-history method 11
6.3.3Modal and spectrum analysis using the required response spectrum
(RRS) 11
6.3.4Static coefficient analysis 12
7Evaluation of the seismic qualification 12
7.1Combination of stresses 12
7.2Acceptance criteria for the seismic waveform 13
7.3Functional evaluation of the test results 13
7.4Allowable stresses 13
8Documentation 13
8.1Information for seismic qualification 13
8.2Test report 14
8.3Analysis report 14
Annex A (normative) Characterisation of the test-set 15
Annex B (informative) Criteria for seismic adequacy of gas-insulated metal-enclosed
switchgear 17
Bibliography 19
Figure 1 – Required response spectrum (RRS) for qualification level moderate 8
Figure 2 – Required response spectrum (RRS) for qualification level high 9
Figure A.1 – Monogram for the determination of equivalent damping ratio 16
Table 1 – Seismic qualification levels for switchgear assemblies – Horizontal severities 6
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –
Part 207: Seismic qualification for gas-insulated
switchgear assemblies for rated voltages above 52 kV
1 Scope
This part of IEC 62271 applies to gas-insulated switchgear assemblies for alternating current of rated voltages above 52 kV for indoor and outdoor installations, including their supporting structure.
For switchgear devices, e.g. live tank circuit breakers, IEC/TR 62271-300 is applicable.
Guidance on interactions between the supporting structure and the soil / foundations is provided in Annex B.
The seismic qualification of the switchgear assemblies takes into account testing of typical switchgear assemblies combined with methods of analysis. Mutual interaction between directly mounted auxiliary and control equipment and switchgear assemblies are covered.
The seismic qualification of switchgear assemblies is only performed upon request.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60068-2-47, Environmental testing – Part 2-47: Tests – Mounting of specimens for vibration, impact and similar dynamic tests
IEC 60068-2-57, Environmental testing – Part 2-57: Tests – Test Ff: Vibration – Time-history method
IEC 60068-3-3:1991, Environmental testing – Part 3: Guidance – Seismic test methods for equipments
IEC 62271-1, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-203, High-voltage switchgear and controlgear – Part 203: Gas-insulated metal- enclosed switchgear for rated voltages above 52 kV
Bibliography
[1]IEC 61462, Composite hollow insulators – Pressurized and unpressurized insulators for use in electrical equipment with rated voltage greater than 1 000 V – Definitions, test methods, acceptance criteria and design recommendations
[2]IEC/TS 61463, Bushings – Seismic qualification
[3]IEC 62155, Hollow pressurized and unpressurized ceramic and glass insulators for use in electrical equipment with rated voltages greater than 1 000 V
[4]IEC 62231, Composite station post insulators for substations with a.c voltages greater than 1 000 V up to 245 kV – Definitions, test methods and acceptance criteria
[5]IEC/TR 62271-300, High-voltage switchgear and controlgear Part 300: Seismic qualification of alternating current circuit-breakers
[6]IEEE 693:2005, IEEE Recommended Practices for Seismic Design of Substations
[7]IEEE C37.122:1993, IEEE Standard for Gas-Insulated Substations