Detail of GB/T 31487.1-2015

Introduction of GB/T 31487.1-2015

GB/T 31487.1-2015 Direct current de-icing devices—Part 1: System design and application guide 1 Scope This part of GB/T 31487 specifies the basic requirements for the system design and application of DC de-icing device, including the design, functional performance, test, technical requirements of main equipment, operation and maintenance of DC de-icing device, etc. This part is applicable to DC de-icing devices based on thyristors for AC transmission lines of 500 kV and below. It may also serve as a reference for DC de-icing devices based on other voltage levels and other power components. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB 311.1 Insulation co-ordination - Part 1: Definitions, principles and rules GB/T 311.2 Insulation co-ordination - Part 2: Application guide GB/T 1094.6 Power transformers - Part 6: Reactors GB 1984 High-voltage alternating-current circuit-breakers GB 1985 High-voltage alternating-current disconnectors and earthing switches GB 3096 Environmental quality standard for noise GB/T 11022 Common specifications for high-voltage switchgear and controlgear standards GB/T 11024.1 Shunt capacitors for a.c. power systems having a rated voltage above 1000V - Part 1: General GB 12348-2008 Emission standard for industrial enterprises noise at boundary GB/T 14549 Quality of electric energy supply - Harmonics in public supply network GB/T 15291 Semiconductor devices - Part 6: Thyristors GB/T 15543 Power quality - Three-phase voltage unbalance GB/T 15945 Power quality - Frequency deviation for power system GB/T 18494.2 Convertor transformers - Part 2: Transformers for HVDC applications GB 20840.2 Instrument transformers - Part 2: Additional requirements for current transformers GB/T 20990.1 Thyristor valves for high voltage direct current (HVDC) power transmission - Part 1: Electrical testing GB/T 20994 Shunt capacitors and AC filter capacitors for HVDC transmission systems GB/T 22389 Guidelines of metal oxide surge arresters without gaps for HVDC converter stations GB/T 25092 Dry-type air-core smoothing reactors for HVDC applications GB/T 26216.1 DC current measuring device for HVDC transmission system - Part 1: Electronic DC current measuring device GB/T 26217 DC voltage measuring device for HVDC transmission system GB/T 29629 Water cooling equipment for static var compensators GB 50060 Code for design of high voltage electrical installation (3~110kV) GB 50147 Erection works of electrical installations - Code for construction and acceptance of high voltage appliance GB 50227 Code for design of installation of shunt capacitors GB 50545-2010 Code for design of 110k V~750kV overhead transmission line IEC 61803 Determination of power losses in high-voltage direct current (HVDC) converter stations with line-commutated converters 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 DC de-icing eliminating line icing by applying direct current to the conducting wire or ground wire of the icing transmission line based on the heating effect of the current 3.2 DC de-icing device device that provides a stable and adjustable direct current for the iced transmission line and heats the line for de-icing 3.3 DC de-icing system system composed of DC de-icing device, power distribution device and de-icing line 3.4 sub-system relatively independent components that make up the DC de-icing device, such as thyristor valves, cooling, filtering, control, protection, etc. 3.5 “one phase to one phase” de-icing mode de-icing connection mode in which two-phase conducting wires are connected in series to form direct current circuit Note: It is also known as “1-1” de-icing mode 3.6 “one phase to two phase” de-icing mode de-icing connection mode in which two-phase conducting wires are connected in parallel and then connected in series with the third phase conductor to form direct current circuit Note: It is also known as “1-2” de-icing mode 3.7 minimum de-icing current critical current for melting the ice on the conducting wire, overhead earth wire or OPGW within a certain time, which is related to environmental conditions (temperature, wind speed, humidity), icing thickness, de-icing time, etc. 3.8 maximum de-icing current maximum allowable current in the de-icing circuit for the purpose of ensuring the safety of equipment in the de-icing circuit, which is related to environmental conditions (temperature, wind speed, humidity), icing conditions, de-icing time, etc. 3.9 design de-icing current current value used to ensure complete detachment of ice on the conducting wire, overhead ground wire, or OPGW within the expected time, which is the product of the minimum de-icing current and the reliability coefficient (usually taken as 1.1), and is related to environmental conditions (temperature, wind speed, humidity), ice thickness, and de-icing time 3.10 rated input voltage of DC de-icing device Rated AC voltage of the DC de-icing device connected to the power supply side 3.11 rated output current of DC de-icing device maximum direct current that can be continuously and stably output by the DC de-icing device under specified service conditions 3.12 rated output voltage of DC de-icing device maximum DC voltage that can be continuously and stably output by the DC de-icing device under the specified service conditions   3.13 rated output power of DC de-icing device maximum DC power that can be continuously and stably output by the DC de-icing device under specified service conditions 3.14 minimum operation current of DC de-icing device minimum direct current without interruption that can be stably output by the DC de-icing device for a long time under the specified service conditions, which is mainly determined by the converter type of the DC de-icing device and the inductance value in the de-icing circuit 3.15 large angle and high current operation operation mode in which DC de-icing device outputs rated direct current output and the firing angle is approximately 90°

Contents of GB/T 31487.1-2015

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Design conditions 4.1 De-icing lines 4.2 Substations equipped with DC de-icing devices 5 System design 5.1 Basic requirements 5.2 Rated parameters on the DC side of DC de-icing device 5.3 Connection mode of DC de-icing device to AC side 5.4 Structure type of DC de-icing device 5.5 Overvoltage protection and insulation coordination of DC de-icing device 5.6 Connection between DC de-icing device and de-icing line 5.7 Installation 5.8 Fire prevention and ventilation 6 Functional performance requirements of DC de-icing device 6.1 General requirements 6.2 Requirements of control function 6.3 Equivalent test requirements 6.4 Fault types and protection function requirements 6.5 Harmonic performance 6.6 Loss 6.7 Audible noise 6.8 Radio interference 7 Technical requirements for main equipment 7.1 Thyristor valve 7.2 Cooling equipment 7.3 Converter transformer 7.4 Smoothing reactors and commutation reactors 7.5 Valve reactor (if any) 7.6 Control and protection devices 7.7 AC side filter 7.8 DC voltage measuring equipment and DC current measuring equipment 7.9 DC side isolating switches and de-icing switches 7.10 DC side arrester 7.11 Other auxiliary equipment 8 Study on operation mode of de-icing 9 Operation and maintenance of DC de-icing device Annex A (Informative) Calculation method and reference value of de-icing current of overhead lines Annex B (Informative) Calculation method and reference value of maximum allowable current for de-icing of overhead lines Annex C (Informative) Main circuit types of DC de-icing device Annex D (Informative) DC de-icing switch and temporary wiring scheme Annex E (Informative) DC de-icing process with de-icing switches on both sides of de-icing line Annex F (Informative) Typical protection configuration of DC de-icing device