1 Scope
This Part of GB/T 18494 applies to oil-immersed three-phase and single-phase convertor transformers for use in HVDC power transmission. It applies to transformers having two, three or multiple windings.
This Part does not apply to:
— Convertor transformers for industrial applications;
— Convertor transformers for traction applications.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this Part of GB/T 18494. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this Part are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies.
GB 1094.1 Power Transformers — Part 1: General (GB 1094.1-1996, eqv IEC 60076-1.1903)
GB 1094.2 Power Transformers — Part 2: Temperature Rise (GB 1094.2-1996, eqv IEC 60076-2:1993)
GB 1094.3 Power Transformers — Part 3: Insulation Levels, Dielectric Tests and External Clearances in Air (GB 1094.3-2003, IEC 60076-3:2000, MOD)
GB 1094.5 Power Transformers — Part 5: Ability to Withstand Short Circuit (GB 1094.5-2003, IEC 60076-5:2000, MOD)
GB/T 1094.10 Power Transformers — Part 10: Determination of Sound Levels (GB/T 1094.10-2003, IEC 60076-10:2001, MOD)
GB/T 2900.15-1997 Electrotechnical Terminology — Transformer, Instrument Transformer, Voltage Regulator and Reactor (neq IEC 60050-421:1990; IEC 60050-321:1986)
GB/T 2900.33-2004 Electrotoechnical Terminology — Power Electronics (IEC 60050-551:1908, IDT)
GB/T 3859.1-1993 Semiconductor Convertors — Specification of Basic Requirements (eqv IEC 60146-1-1:1991)
GB/T 3859.2-1993 Semiconductor Convertors — Application Guide (eqv IEC 60146-1-2:1991)
GB/T 4109 Technical Specification of High Voltage Bushing (GB/T 4109-1999, eqv IEC 60137:1995)
GB/T 7354-2003 Partial Discharge Measurements (IEC 60270:2000, IDT)
GB 10230 On-load Tap-changers (GB 10230-1988, eqv IEC 60214:1987)
GB/T 13499-2002 Power Transformers — Application Guide (idt IEC 60076-8:1997)
GB/T 15164-1994 Loading Guide for Oil-immersed Power Transformers (idt IEC 60354:1991)
GB/T 17623-1998 Determination of Componental Contents of Gases Dissolved in Insulating Oil by Gas Chromatography Method (neq IEC 60567:1992)
GB/T 18494.1-2001 Convertor Transformers — Part 1: Transformers for Industrial Applications (idt IEC 61378-1:1997)
3 Terms and Definitions
Contents
Foreword III
Introduction V
1 Scope
2 Normative References
3 Terms and Definitions
4 Service Conditions
4.1 General
4.2 Temperature
4.3 Load current
4.4 Direction of power flow
5 List of Variables
6 Ratings
6.1 General
6.2 Rated voltage
6.3 Rated current
6.4 Rated frequency
6.5 Rated power
7 Tolerances
7.1 General
7.2 Short-circuit impedance tolerances
7.3 Guarantees
8 Losses
8.1 General
8.2 No-load loss
8.3 Load loss under rated power-frequency conditions
8.4 Load loss under service conditions
8.5 Determination of hot-spot temperature
9 Insulation Levels
9.1 Line windings
9.2 Valve windings
9.3 Induced voltage level with partial discharge measurements
10 Sound Level
10.1 General
10.2 Guaranteed sound-power levels
10.3 Sound-power level at site
11 Testing
11.1 General
11.2 Tests
11.3 Load-loss measurements
11.4 Factory dielectric tests
11.5 Temperature-rise test
11.6 Load-current test
11.7 Determination of transformer sound-power level
12 High-frequency Modelling
13 Loading of Transformer Above Rating
14 Bushings
14.1 AC bushings
14.2 Valve winding bushings
15 Tap-changer
15.1 General
15.2 Current wave shape
