BSI 20/30428912 DC:2020 Edition
$13.70
BS IEC 63253-5713-8. Station Service Voltage Transformers (SSVT)
Published By | Publication Date | Number of Pages |
BSI | 2020 | 84 |
PDF Catalog
PDF Pages | PDF Title |
---|---|
1 | 30428912 |
3 | 38_633e_CD |
10 | FOREWORD |
12 | Scope Normative references |
13 | Terms and definitions |
14 | 3.1 General definitions 3.1.1 Station Service Voltage Transformer 3.1.2 Enclosure 3.1.3 Primary terminal 3.1.4 Secondary terminals 3.1.5 Secondary circuit 3.1.6 Pressure relief device 3.2 Definitions related to voltage and dielectric aspects 3.2.1 Nominal system voltage 3.2.2 Highest voltage of a system / Maximum system voltage |
15 | 3.2.3 Highest voltage for equipment / Maximum equipment voltage 3.2.4 Rated primary voltage 3.2.5 Rated secondary voltage 3.2.6 Harmonic factor 3.2.7 Rated voltage factor 3.2.8 Rated insulation level 3.2.9 Earth fault factor 3.2.10 Effectively earthed neutral system / grounded neutral system 3.2.11 Solidly earthed neutral system |
16 | 3.3 Definitions related to windings 3.3.1 Winding 3.3.2 Primary winding 3.3.3 Secondary windings 3.3.4 Power windings 3.3.5 Metering and relaying/protection windings 3.3.6 Section 3.3.7 Tapped windings 3.4 Definitions related to ratings 3.4.1 Rating 3.4.2 Rated quantities 3.4.3 Rated frequency 3.4.4 Rated power |
17 | 3.4.5 Rated current 3.4.6 Temperature rise 3.5 Definitions related to losses and no-load current 3.5.1 No-load loss 3.5.2 No-load current 3.5.3 Load loss 3.5.4 Total loss 3.6 Definitions related to short-circuit impedance and voltage drop 3.6.1 Short-circuit impedance |
18 | 3.6.2 Voltage drop or rise for a specified load condition (voltage regulation) 3.7 Definitions related to gas insulation 3.7.1 Closed pressure system 3.7.2 Rated filling pressure 3.7.3 Minimum functional pressure 3.7.4 Absolute leakage rate 3.7.5 Relative leakage rate 3.8 Definitions related to other ratings 3.8.1 Rated arc proof current |
19 | 3.9 Index of abbreviations Service conditions 4.1 Normal (Usual) service conditions 4.1.1 General 4.1.2 Temperature 4.1.3 Altitude 4.1.4 Primary voltage 4.1.5 Load current 4.1.6 Operation above rated voltage or below rated frequency 4.1.6.1 Capability |
20 | 4.1.6.2 Maximum continuous transformer operating voltage 4.1.6.3 Voltage Factor (Fv) 4.1.7 Outdoor operation 4.1.8 Step-down operation 4.1.9 Tank or enclosure finish 4.2 Loading beyond rated power |
21 | 4.3 Special (Unusual) service conditions 4.3.1 Special (Unusual) temperature 4.3.2 Dielectric strength correction factor for altitudes greater than 1000 m |
22 | 4.3.3 Other special (unusual) service conditions |
23 | Rating Data 5.1 Secondary voltage 5.2 Cooling classes of transformers 5.3 Frequency 5.4 Rated power 5.5 Voltage ratings and taps 5.5.1 General 5.5.2 Voltage ratings 5.5.3 Ratings of transformer taps 5.5.4 Voltage drop or rise (Voltage regulation) for a specified load condition |
24 | 5.6 Connections 5.7 Polarity and terminal markings 5.7.1 Polarity of single-phase transformers 5.7.2 Terminal markings 5.8 Turns ratio 5.8.1 General 5.8.2 Taps 5.9 Metering winding accuracy ratings 5.9.1 General |
25 | 5.9.2 Assignment of accuracy ratings 5.9.3 Accuracy classification for SSVT transformer with two secondary metering windings or tapped secondary windings 5.10 Short circuit impedance 5.11 Total losses 5.12 Insulation levels |
26 | 5.13 Creepage distance requirements |
27 | 5.14 Basic lightning impulse insulation level (BIL) 5.15 Switching impulse insulation level 5.16 Neutral terminals 5.17 An SSVT may have multiple neutral terminals, in case of tapping the primary winding at the neutral end, in order to adjust the SSVT’s voltage ratio. Insulation resistance requirements 5.18 Ground shield requirements 5.19 Dissolved gas and water content requirements for new oil-immersed SSVTs 5.20 Internal arc requirements |
28 | 5.20.1 Internal arc protection class I 5.20.2 Internal arc protection class II 5.21 Temperature rise and loading conditions for SSVT |
29 | 5.22 Transmitted overvoltages (TOV) |
31 | 5.23 Nameplates 5.23.1 General |
32 | Construction 6.1 Tank pressure requirements for liquid-immersed SSVTs 6.2 Mechanical performance requirements 6.2.1 Sealing tests 6.2.1.1 General 6.2.1.2 Oil-immersed SSVTs 6.2.1.3 Gas-filled SSVTs |
33 | 6.2.2 Mechanical strength of the transformer |
34 | 6.3 Liquid insulation system 6.3.1 Insulating liquids 6.3.2 Insulating liquid preservation 6.4 Gas insulation system 6.4.1 Requirements for gases in SSVT |
35 | 6.4.2 Pressure monitoring devices 6.4.3 Tank construction and maximum gas leakage rates 6.5 Grounding 6.5.1 Transformer grounding |
36 | 6.5.2 Grounding of core 6.6 Degrees of protection by enclosures 6.6.1 General 6.6.2 Protection of persons against access to hazardous parts and protection of the equipment against ingress of solid foreign objects |
37 | 6.6.3 Protection against ingress of water 6.6.3.1 General 6.6.3.2 Recommended protection level 6.6.4 Protection of equipment against mechanical impact under normal service conditions Short-circuit characteristics 7.1 Requirements 7.1.1 General 7.1.2 Short-circuit current duration 7.1.2.1 General |
38 | 7.1.2.2 Duration of short-circuit tests 7.1.2.3 Number of short-circuit shots 7.1.3 Short-circuit current magnitude 7.1.4 Short-circuit current calculations 7.1.4.1 Symmetrical current 7.1.4.2 Asymmetrical current 7.1.5 Temperature limits of transformers for short-circuit conditions |
39 | 7.2 Calculation of winding temperature during a short circuit 7.3 Criteria for the short-time mechanical and thermal rating test |
40 | Tests 8.1 General 8.2 Dielectric tests 8.2.1.1 Dielectric tests at factory 8.2.1.2 Dielectric tests by end user 8.3 Routine, type, and special tests for transformers |
42 | 8.3.1 General 8.3.2 Routine tests 8.3.3 Type tests 8.3.4 Special tests |
43 | 8.4 Routine test procedures 8.4.1 Resistance measurement of windings 8.4.2 Verification of terminal markings and polarity 8.4.3 Winding insulation resistance 8.4.4 No-load losses and excitation current measurement 8.4.5 Load losses and impedance voltage measurements |
44 | 8.4.6 Capacitance and dissipation factor requirements |
45 | 8.4.7 Applied voltage tests 8.4.7.1 General 8.4.7.2 Applied voltage test on the neutral terminal 8.4.7.3 Applied voltage test on secondary windings 8.4.7.3.1 Applied voltage test on secondary power windings 8.4.7.3.2 Applied voltage test on secondary measuring windings 8.4.8 Induced voltage test |
46 | 8.4.9 Partial discharge test |
48 | 8.4.10 Routine leak test 8.4.10.1 Routine leak test for oil-immersed SSVTs 8.4.10.2 Routine leak test for gas-filled SSVTs 8.4.11 Routine accuracy performance test 8.4.11.1 Power windings 8.4.11.2 Measuring / protection windings 8.4.12 Lightning impulse tests |
49 | 8.4.12.1 Test procedure and criteria 8.4.12.2 Chopped-wave test |
50 | 8.4.12.3 Transformer connections for impulse test on line terminal 8.4.13 Ground shield check 8.5 Type test procedures 8.5.1 Dissolved gas and water content analysis |
51 | 8.5.2 Mechanical test 8.5.2.1 General 8.5.2.2 Test procedure for high voltage terminals 8.5.2.3 Test procedure for low voltage terminals |
52 | 8.5.3 Lightning impulse voltage test on the primary winding |
53 | 8.5.4 Switching impulse voltage test in wet conditions |
54 | 8.5.5 External radio influence voltage (RIV) test 8.5.5.1 General 8.5.5.2 RIV test performed according to CISPR 18-2 |
56 | 8.5.5.3 RIV test performed according to NEMA 107 |
57 | 8.5.5.4 Test voltages and maximum RIV voltage 8.5.6 Induced voltage test in wet conditions |
58 | 8.5.7 Temperature rise test 8.5.7.1 General 8.5.7.2 Ambient or cooling air temperature 8.5.7.3 Temperature rise measurements |
59 | 8.5.7.4 Determination of winding temperature at time of shutdown 8.5.7.5 Determination of average temperature by the resistance method |
60 | 8.5.7.6 Determination of temperature rise from temperature measurements 8.5.7.7 Correction of observed temperature rise for variation in altitude 8.5.7.8 Test methods 8.5.7.8.1 Actual loading |
61 | 8.5.7.8.2 Simulated loading 8.5.7.8.2.1 Loading back method |
63 | 8.5.7.8.2.2 Short-circuit method 8.5.7.8.2.3 Open-circuit and short circuit method 8.6 Special test procedures 8.6.1 Endurance chopped wave test for liquid filled SSVT 8.6.1.1 General |
64 | 8.6.1.2 Test Sequence 8.6.1.3 Requirements of the applied wave 8.6.1.4 Chopping device 8.6.1.5 SSVT connections 8.6.1.6 Measurement of voltage and current 8.6.1.7 Detection of failure |
65 | 8.6.2 Internal arc test 8.6.2.1 Test prerequisites and documentation 8.6.2.2 Requirement of the fuse wire installation 8.6.2.3 Test conditions |
67 | 8.6.2.4 Test Requirements 8.6.3 Low Temperature Sealing system test for gas-filled SSVTs 8.6.3.1 Evaluation Criteria 8.6.3.2 Test procedure 8.6.3.3 Test set-up |
68 | 8.6.3.4 Test sequence 8.6.4 Seismic qualification 8.6.5 Verification of the degree of protection by enclosures 8.6.5.1 Verification of the IP coding 8.6.6 Transmitted overvoltage test |
70 | 8.6.7 Short circuit test 8.7 Determination of thermal duplicate temperature-rise data 8.8 Frequency conversion of transformer performance parameters (50/60 Hz) 8.9 Test data |
71 | Tolerances 9.1 Tolerances for ratio 9.2 Tolerances for impedance 9.3 Tolerances for losses |
72 | 9.4 Accuracies required for measuring losses |
73 | Bibliography |
77 | Annex A (informative) Dielectric tests performed at an altitude of 1000 m (3300 ft) or less for SSVTs designed for installation at altitudes greater than 1000 m (3300 ft) |
78 | Annex B (informative) Temperature Rise Testing Considerations B.1 Heating and cooling curves |
79 | B.2 Temperature stabilization B.3 Effect of shutting off power to take resistance measurements B.4 Use of cooling curve to extrapolate to time of shutdown |
80 | B.5 Use of heating or cooling to determine thermal time constant |
81 | Annex C (informative) Internal arc protection for SSVT |
82 | Annex D (informative) Technical information exchange during contracting stage D.1 General D.2 System Information D.3 Ratings |
83 | Annex E (Normtive) Temperature correction of load loss and impedance voltage E.1 |