BS EN 60099-5:2013
$215.11
Surge arresters – Selection and application recommendations
| Published By | Publication Date | Number of Pages |
| BSI | 2013 | 150 |
This part of IEC 60099 is not a mandatory standard but provides information, guidance, and recommendations for the selection and application of surge arresters to be used in threephase systems with nominal voltages above 1 kV. It applies to gapless metal-oxide surge arresters as defined in IEC 60099-4, to surge arresters containing both series and parallel gapped structure – rated 52 kV and less as defined in IEC 60099-6 and metal-oxide surge arresters with external series gap for overhead transmission and distribution lines (EGLA) as defined in IEC 60099-8. In Annex H, some aspects regarding the old type of SiC gapped arresters are discussed.
The principle of insulation coordination for an electricity system is given in IEC 60071 and IEC 60071-2 standards. Basically the insulation coordination process is a risk management aiming to ensure the safe, reliable and economic design and operation of high voltage electricity networks and substations. The use of surge arrester helps to achieve a system and equipment insulation level and still maintaining an acceptable risk and the best economic of scale.
The introduction of analytical modelling and simulation of power system transients further optimise the equipment insulation level. The selection of surge arresters has become more and more important in the power system design and operation. It is worthwhile to note that the reliability of the power system and equipment is dependent on the safety margin adopted by the user in the design and selection of the equipments and surge arresters.
Surge arrester residual voltage is a major parameter of which most users have paid a lot of attention to when selecting the type and rating. The typical maximum surge arresters residual voltage are given in Annex F. It is likely, however, that for some systems, or in some countries, the system reliability requirements and design are sufficiently uniform that the recommendations of the present standard may lead to the definition of narrow ranges of arresters. The user of surge arresters will, in that case, not be required to apply the whole process introduced here to any new installation and the selection of characteristics resulting from prior practice may be continued.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 7 | CONTENTS |
| 11 | 1 Scope 2 Normative references |
| 21 | 4 General principles for the application of surge arresters |
| 22 | 5 Surge arrester fundamentals and applications issues 5.1 Evolution of surge protection equipment |
| 23 | 5.2 Different types and designs and their electrical and mechanical characteristics 5.2.1 General 5.2.2 Metal-oxide arresters without gaps according to IEC 60099-4 |
| 28 | Figures Figure 1 – GIS arresters of three mechanical/one electrical column (middle) and one column (left) design and current path of the three mechanical/one electrical column design (right) |
| 29 | Figure 2 – Typical deadfront arrester |
| 33 | 5.2.3 Metal-oxide surge arresters with internal series gaps according to IEC 60099-6 Figure 3 – Internally gapped metal-oxide surge arrester designs |
| 35 | 5.2.4 Externally gapped line arresters (EGLA) according to IEC 60099-8:2011 Figure 4 – Components of an EGLA acc. to IEC 60099-8 |
| 38 | 5.3 Installation considerations for arresters 5.3.1 High-voltage station arresters |
| 39 | Figure 5 – Examples of UHV and HV arresters with grading and corona rings |
| 40 | Figure 6 – Same type of arrester mounted on a pedestal (left), suspended from an earthed steel structure (middle) or suspended from a line conductor (right |
| 42 | Figure 7 – Typical arrangement of a 420-kV arrester |
| 43 | Figure 8 – Installations without earth-mat (distribution systems) Figure 9 – Installations with earth-mat (high-voltage substations) |
| 45 | Figure 10 – Definition of mechanical loads according to IEC 60099-4 Tables Table 1 – Minimum mechanical requirements (for porcelain-housed arresters) |
| 46 | 5.3.2 Distribution arresters |
| 47 | Figure 11 – Distribution arrester with disconnector and insulating bracket |
| 48 | Figure 12 – Examples of good and poor earthingprinciples for distribution arresters |
| 49 | 5.3.3 Line surge arresters (LSA) |
| 50 | 6 Insulation coordination and surge arrester applications 6.1 General |
| 51 | 6.2 Insulation coordination overview 6.2.1 General 6.2.2 IEC insulation coordination procedure 6.2.3 Overvoltages |
| 52 | Figure 13 – Typical voltages and duration example for an efficiently earthed system |
| 53 | Figure 14 – Typical phase-to-earth overvoltages encountered in power systems |
| 54 | Figure 15 – Arrester Voltage-Current Characteristics |
| 56 | 6.2.4 Line insulation coordination: Arrester Application Practices |
| 58 | Figure 16 – Direct strike to a phase conductor with LSA |
| 59 | Figure 17 – Strike to a shield wire or tower with LSA |
| 61 | 6.2.5 Substation insulation coordination: Arrester application practices |
| 65 | 6.2.6 Insulation coordination studies |
| 66 | 6.3 Selection of arresters 6.3.1 General |
| 67 | Figure 18 – Typical procedure for a surge arrester insulation coordination study |
| 68 | 6.3.2 General procedure for the selection of surge arresters |
| 70 | Figure 19 – Flow diagrams for standard selection of surge arrester |
| 71 | Figure 20 – Examples of arrester TOV capability |
| 72 | Table 2 – Arrester classification for surge arresters |
| 77 | Table 3 – Definition of factor A in formulas (15) to (17) for various overhead lines Table 4 – Examples for protective zones calculated by formula (17) for open-air substations |
| 78 | 6.3.3 Selection of line surge arresters, LSA |
| 80 | Figure 21 – Flow diagram for the selection of NGLA |
| 84 | Figure 22 – Flow diagram for the selection of EGLA |
| 86 | Table 5 – Example of the condition for calculating lightningcurrent duty of EGLA in 77 kV transmission lines |
| 87 | 6.3.4 Selection of arresters for cable protection Table 6 – Probability of insulator flashover in Formula (19) |
| 89 | 6.3.5 Selection of arresters for distribution systems – special attention |
| 90 | Figure 23 – Common neutral configurations |
| 91 | 6.3.6 Selection of UHV arresters |
| 92 | 6.4 Normal and abnormal service conditions 6.4.1 Normal service condition 6.4.2 Abnormal service conditions |
| 95 | 7 Surge arresters for special applications 7.1 Surge arresters for transformer neutrals 7.1.1 General 7.1.2 Surge arresters for fully insulated transformer neutrals |
| 96 | 7.1.3 Surge arresters for neutrals of transformers with non-uniform insulation 7.2 Surge arresters between phases |
| 97 | 7.3 Surge arresters for rotating machines Figure 24 – Typical configurations for arresters connected phase-to-phaseand phase-to-ground |
| 98 | 7.4 Surge arresters in parallel 7.4.1 General |
| 99 | 7.4.2 Combining different designs of arresters 7.5 Surge arresters for capacitor switching |
| 101 | 7.6 Surge arresters for series capacitor banks 8 Asset management of surge arresters 8.1 General 8.2 Managing surge arresters in a power grid 8.2.1 Asset database 8.2.2 Technical specifications |
| 102 | 8.2.3 Strategic spares 8.2.4 Transportation and storage 8.2.5 Commissioning 8.3 Maintenance 8.3.1 General |
| 103 | 8.3.2 Polluted arrester housing 8.3.3 Coating of arrester housings |
| 104 | 8.3.4 Inspection of disconnectors on surge arresters 8.3.5 Line surge arresters 8.4 Performance and diagnostic tools 8.5 End of life 8.5.1 General 8.5.2 GIS arresters |
| 105 | 8.6 Disposal and recycling |
| 106 | Annex A (informative)Determination of temporary overvoltagesdue to earth faults |
| 107 | Figure A.1 – Earth fault factor k on a base of X0/X1 , for R1/X1 = R1= 0 Figure A.2 – Relationship between R0/X1 and X0/X1 for constant values of earth fault factor k where R1 = 0 |
| 108 | Figure A.3 – Relationship between R0/X1 and X0/X1 for constant values of earth fault factor k where R1 = 0,5 X1 Figure A.4 – Relationship between R0/X1 and X0/X1 for constant values of earth fault factor k where R1 = X1 |
| 109 | Figure A.5 – Relationship between R0/X1 and X0/X1 for constant valuesof earth fault factor k where R1 = 2X1 |
| 110 | Annex B (informative) Current practice |
| 111 | Annex C (informative) Arrester modelling techniques for studies involvinginsulation coordination and energy requirements Figure C.1 – Schematic sketch of a typical arrester installation |
| 112 | Figure C.2 – Increase in residual voltage as functionof virtual current front time |
| 113 | Figure C.3 – Arrester model for insulation coordination studies – fast- front overvoltages and preliminary calculation (Option 1) Figure C.4 – Arrester model for insulation coordination studies – fast- front overvoltages and preliminary calculation (Option 2) Figure C.5 – Arrester model for insulation coordination studies – slow-front overvoltages. |
| 114 | Annex D (informative) Diagnostic indicators of metal-oxide surge arresters in service |
| 116 | Figure D.1 – Typical leakage current of a non-linear metal-oxide resistor in laboratory conditions |
| 117 | Figure D.2 – Typical leakage currents of arresters in service conditions |
| 118 | Figure D.3 – Typical voltage-current characteristics for non-linear metal-oxide resistors Figure D.4 – Typical normalized voltage dependence at +20 °C |
| 119 | Figure D.5 – Typical normalized temperature dependence at Uc |
| 120 | Figure D.6 – Influence on total leakage current by increase in resistive leakage current |
| 122 | Figure D.7 – Measured voltage and leakage current and calculated resistive and capacitive currents (V = 6,3 kV r.m.s) |
| 123 | Figure D.8 – Remaining current after compensation by capacitive current at Uc |
| 124 | Figure D.9 – Error in the evaluation of the leakage current third harmonic for differentphase angles of system voltage third harmonic, considering various capacitances and voltage-current characteristics of non-linear metal-oxide resistors |
| 126 | Figure D.10 – Typical information for conversion to “standard”operating voltage conditions Figure D.11 – Typical information for conversion to “standard”ambient temperature conditions |
| 127 | Table D.1 – Summary of diagnostic methods Table D.2 – Properties of on-site leakage current measurement methods |
| 128 | Annex E (informative) Typical data needed from arrester manufacturersfor proper selection of surge arresters Table E.1 – Arrester data needed for the selection of surge arresters |
| 129 | Annex F (informative) Typical maximum residual voltages for metal-oxide arresterswithout gaps according to IEC 60099-4 Table F.1 – Residual voltages for 20 000 A and 10 000 A arrestersin per unit of rated voltage Table F.2 – Residual voltages for 5 000 A, 2 500 A and 1 500 Aarresters in per unit of rated voltage |
| 130 | Annex G (informative) Steepness reduction of incoming surge with additional lineterminal surge capacitance |
| 131 | Figure G.1 – Surge voltage waveforms at various distancesfrom strike location (0,0 km) due to corona |
| 133 | Table G.1 – Cs impact on steepness ratio fs and steepness Sn Table G.2 Change in coordination withstand voltage, Ucw |
| 134 | Figure G.2 – Case 1: EMTP Model: Thevenin equivalent source,line (Z,c) & station bus (Z,c) & Cap (Cs) |
| 135 | Figure G.3 – Case 2: Capacitor Voltage charge via line Z: u(t) = 2xUs x (1 – exp[- t/(ZxC]) |
| 136 | Figure G.4 – EMTP model Figure G.5 – Simulated surge voltages at the line-station bus interface |
| 137 | Figure G.6 – Simulated Surge Voltages at the Transformer Figure G.7 – EMTP Model |
| 138 | Figure G.8 – Simulated surge voltages at the line-station bus interface Figure G.9 – Simulated surge voltages at the transformer |
| 139 | Annex H (informative) End of life and replacement of old gapped SiC-arresters |
| 140 | Figure H.1 – Internal SiC-arrester stack |
| 144 | Bibliography |
