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°
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
直流融冰装置
第1部分：系统设计和应用导则
1 范围
GB/T 31487的本部分规定了直流融冰装置系统设计和应用的基本要求，包括直流融冰装置的设计、功能性能、试验、主要设备技术要求、运行和维护等。
本部分适用于500 kV及以下交流输电线路的基于晶闸管的直流融冰装置，其他电压等级和基于其他功率器件的直流融冰装置可参照本部分。
2 规范性引用文件
下列文件对于本文件的应用是必不可少的。凡是注日期的引用文件，仅注日期的版本适用于本文件。凡是不注日期的引用文件，其最新版本（包括所有的修改单）适用于本文件。
GB 311.1 绝缘配合 第1部分：定义、原则和规则
GB/T 311.2 绝缘配合 第2部分：使用导则
GB/T 1094.6 电力变压器 第6部分：电抗器
GB 1984 高压交流断路器
GB 1985 高压交流隔离开关和接地开关
GB 3096 声环境质量标准
GB/T 11022 高压开关设备和控制设备标准的共用技术要求
GB/T 11024.1 标称电压1000 V以上交流电力系统用并联电容器 第1部分：总则
GB 12348—2008 工业企业厂界环境噪声排放标准
GB/T 14549 电能质量 公用电网谐波
GB/T 15291 半导体器件 第6部分 晶闸管
GB/T 15543 电能质量 三相电压不平衡
GB/T 15945 电能质量 电力系统频率偏差
GB/T 18494.2 变流变压器 第2部分：高压直流输电用换流变压器
GB 20840.2 互感器 第2部分：电流互感器的补充技术要求
GB/T 20990.1 高压直流输电晶闸管阀 第1部分：电气试验
GB/T 20994 高压直流输电系统用并联电容器及交流滤波电容器
GB/T 22389 高压直流换流站无间隙金属氧化物避雷器导则
GB/T 25092 高压直流输电用干式空心平波电抗器
GB/T 26216.1 高压直流输电系统直流电流测量装置 第1部分：电子式直流测量装置
GB/T 26217 高压直流输电系统直流电压测量装置
GB/T 29629 静止无功补偿装置水冷却设备
GB 50060 3～110 kV高压配电装置设计规程
GB 50147 电气装置安装工程 高压电器施工及验收规范
GB 50227 并联电容器装置设计规范
GB 50545—2010 110 kV～750 kV架空输电线路设计规范
IEC 61803 采用电网换相换流器的高压直流（HVDC）换流站站功率损耗的确定（Determination of power losses in high-voltage direct current （HVDC） converter stations with line-commutated converters）
3 术语和定义
下列术语和定义适用于本文件。
3.1
直流融冰 DC de-icing
对覆冰输电线路导线或地线施加直流电流，利用电流加热效应消除线路覆冰。
3.2
直流融冰装置 DC de-icing device
为覆冰输电线路提供稳定且可调的直流电流，对线路加热以使覆冰融化的装置。
3.3
直流融冰系统 DC de-icing system
由直流融冰装置、电源配电装置和融冰线路等组成的系统。
3.4
子系统 sub-system
组成直流融冰装置的功能相对独立的各个部分，例如晶闸管阀、冷却、滤波、控制、保护等。
3.5
“一相对一相”融冰方式 “one phase to one phase” de-icing mode
线路两相导线串联形成直流电流回路的融冰接线方式。
注：也称“1-1”融冰方式。
3.6
“一相对两相”融冰方式 “one phase to two phase” de-icing mode
线路两相导线并联后和第三相导线串联形成直流电流回路的融冰接线方式。
注：也称“1-2”融冰方式。
3.7
最小融冰电流 minimum de-icing current
在确定的时间内使导线、架空地线或光纤复合地线（OPGW）上覆冰融化的临界电流，与环境条件（温度、风速、湿度）、覆冰厚度、融冰时间等相关。
3.8
最大融冰电流 maximum de-icing current
为保证融冰时融冰回路中设备的安全，融冰回路中允许通过的最大电流，与环境条件（温度、风速、湿度）、覆冰情况、融冰时间等相关。
3.9
设计融冰电流 design de-icing current
为保证导线、架空地线或光纤复合地线（OPGW）上覆冰在预期时间内完全脱落采用的电流值，为最小融冰电流值与可靠系数（一般取1.1）的乘积，与环境条件（温度、风速、湿度）、覆冰厚度、融冰时间等相关。
3.10
直流融冰装置额定输入电压 rated input voltage of DC de-icing device
直流融冰装置接入电源侧的额定交流电压。
3.11
直流融冰装置额定输出电流 rated output current of DC de-icing device
在规定的使用条件下，直流融冰装置能持续且稳定输出的最大直流电流。
3.12
直流融冰装置额定输出电压 rated output voltage of DC de-icing device
在规定的使用条件下，直流融冰装置能持续且稳定输出的最大直流电压。
3.13
直流融冰装置额定输出功率 rated output power of DC de-icing device
在规定的使用条件下，直流融冰装置能持续且稳定输出的最大直流功率。
3.14
直流融冰装置最小运行电流 minimum operation current of DC de-icing device
在规定的使用条件下，直流融冰装置能长时间稳定输出的不出现断续的最小直流电流，主要由直流融冰装置换流器型式和融冰回路中电感值决定。
3.15
大角度大电流运行 large angle and high current operation
直流融冰装置输出额定直流电流且触发角近似90°的运行方式。
3.16
开路试验 open line test
直流侧开路，将直流输出电压升至设定值，检查直流融冰装置等设备的直流电压控制功能和电压承受能力。
注：也称空载加压试验或空载升压试验。
3.17
零功率试验 zero power test
直流融冰装置直流侧经电抗器短接，将直流电流升至设定值，检查直流融冰装置直流电流控制功能及电流承受能力。
3.18
工频感应电压 induced voltage of power frequency
在融冰期间，邻近运行的交流线路在直流融冰回路中感应出的工频电压。
3.19
工频感应电流 induced current of power frequency
在融冰期间，邻近运行的交流线路在直流融冰回路中感应出的工频电流。
3.20
均流系数 coefficient of current distribution
直流融冰装置晶闸管阀采用双桥并联型式时，并联运行支路电流的平均值与最大支路电流值之比。
4 设计条件
4.1 融冰线路
主要包括：
a）电压等级（kV）；
b）导线型式、长度（km）、直流电阻（Ω）、电感（H）、电容（F）等；
c）架空地线和/或光纤复合地线（OPGW）型式、长度（km）、直流电阻（Ω）、电感（H）、电容（F）等；
d）线路最大覆冰厚度（mm）；
e）串联在融冰回路中的线路阻波器、隔离开关、断路器、电流互感器等设备的参数；
f）与融冰回路并联的高压并联电抗器、电压互感器等设备的参数；
g）与融冰线路同塔、平行或交叉跨越线路情况，主要包括线路电压等级、导线型式和平行段长度等；
h）融冰线路上安装的其他设备的参数；
i）直流融冰装置应满足变电站的融冰需求，包括规划线路和可能串联融冰的线路。
4.2 配置直流融冰装置的变电站
4.2.1 环境条件
主要包括：
a）海拔（m）；
b）年均降水量（mm）；
c）最大月降水量（mm）；
d）年平均环境温度（℃）；
e）最高环境温度（℃）；
f）最低环境温度（℃）；
g）年平均相对湿度（％）；
h）最大相对湿度（％）；
i）最大地面积雪厚度（mm）；
j）最大结霜厚度（mm）；
k）冻土层厚度（m）；
l）年平均风速（m/s）；
m）年最大风速（m/s）；
n）地震震级（级）；
o）年平均雷暴日数（d/a）；
p）污秽等级及盐密（ESDD）（级、mg/cm2）；
