Direct current de-icing devices—Part 2: Thyristor valves
1 Scope
This part of GB/T 31487 specifies the basic requirements for the function, design and test of thyristor valves of DC de-icing devices.
This part is applicable to water cooling thyristor valves of DC de-icing devices. It may also serve as a reference for thyristor valves adopting other cooling methods.
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/T 3859.1-2013 Semiconductor converters - General requirements and line commutated converters - Part 1-1: Specification of basic requirements
GB/T 13498 Terminology for high-voltage direct current (HVDC) transmission
GB/T 16927.1 High-voltage test techniques - Part 1: General definitions and test requirements
GB/T 20990.1-2007 Thyristor valves for high voltage direct current (HVDC) power transmission - Part 1: Electrical testing
GB 50150-2006 Standard for hand-over test of electric equipment electric equipment installation engineering
IEC/TS 60815-1: 2008 Selection dimensioning of high-voltage insulators intended fuse in polluted conditions - Part 1: Definitions, information general principles
IEC 61803: 2011 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 terms and definitions given in GB/T 13498 and the following apply.
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3.1
valve
electrical and mechanical combination composed of power electronic devices and auxiliary components, which can realize unidirectional or bidirectional conduction
Note: At present, the commonly used valves include diode valves, thyristor valves, insulated-gate bipolar transistors (IGBT), etc.
3.2
thyristor valve
valve whose power electronic devices are thyristor valves
3.3
converter
electrical device capable of realizing complete commutation function
3.4
single valve
valve composed of several thyristor levels in series, which is an arm of 6-pulse converter
3.5
thyristor level
component of a valve, which consists of a thyristor or several parallel thyristors and auxiliary equipment adjacent to them
3.6
valve electronics
electronic circuit that performs control, monitoring and protection functions at valve potential
3.7
valve base electronics
electronic equipment that provides an interface between a ground potential control equipment and valve electronics or valve device, also known as a valve interface electronic equipment
3.8
firing angle
time from the forward zero crossing of the ideal sinusoidal commutation voltage to the beginning of the forward current conduction, measured from an electrical angle
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3.9
rated direct current
direct current (average value) output by the converter according to the specified load conditions and service conditions
3.10
maximum direct current
maximum direct current output by the converter to the load under specified operating conditions (theoretically within an infinite time)
Note: Generally, there are different values under different cooling media and ambient temperature.
3.11
2h overload direct current
direct current that the converter can output to the load within the specified 2h
Note: Generally, there are different values under different cooling media and ambient temperature.
3.12
maximum ideal no-load direct voltage
maximum direct voltage (Udi0max) of the converter under no-load condition
Note: At this time, all kinds of voltage drops and grid voltage fluctuation factors are ignored.
3.13
rated direct voltage
average value that the direct voltage output by converter shall reach under the specified conditions
3.14
rated direct power
product of rated direct voltage and rated direct current of converter
3.15
coefficient of current distribution
ratio of the average value of branch current in parallel operation to the maximum branch current value when the thyristor valve of DC de-icing device adopts double-bridge parallel connection type
3.16
rated junction temperature
maximum junction temperature allowed for normal operation of thyristor
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3.17
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°
3.18
zero power test
test for inspecting the direct current control function and current withstand capacity of the DC de-icing device, in which the direct current side of the DC de-icing device is short-circuited through a reactor and the direct current is increased to the set value
4 Technical requirements
4.1 Environmental conditions
The normal use environment conditions of thyristor valve of DC de-icing device include the following aspects:
a) the altitude is less than 2,000m;
b) the ambient temperature is not less than -20°C and not higher than 50°C;
c) the maximum relative humidity is 85% (below 20°C);
d) the pollution grade is b;
e) the magnitude of the earthquake is not more than Grade 8;
f) the frequency fluctuation range of AC power grid shall not exceed ±5%.
Note 1: When the altitude is greater than 2,000m, the altitude correction design shall be carried out according to relevant standards.
Note 2: The outdoor pollution grades are designed generally according to Grade d in IEC/TS 60815-1: 2008.
4.2 Access system
The converter of DC de-icing device should be connected to the low voltage side (10kV or 35kV) of the main transformer meeting the de-icing capacity requirements through special converter transformer or commutation reactor, or directly connected to the low voltage side of the main transformer. Otherwise, it shall be connected to the upper power bus through a special transformer.
4.3 Load properties
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Technical requirements
4.1 Environmental conditions
4.2 Access system
4.3 Load properties
4.4 Functional requirements
5 Electrical connection type of thyristor valve
6 Design of thyristor valve
6.1 Electrical design of thyristor valve
6.2 Mechanical design of thyristor valve
6.3 Thermal design of thyristor valve
7 Tests
7.1 Introduction
7.2 Type test and routine test
7.3 Field test
Annex A (Normative) Loss calculation method of thyristor valve
直流融冰裝置 第2部分：晶閘管閥
1 范圍
GB/T 31487的本部分規(guī)定了直流融冰裝置晶閘管閥的功能、設(shè)計(jì)和試驗(yàn)等的基本要求。
本部分適用于直流融冰裝置水冷卻晶閘管閥，采用其他冷卻方式的晶閘管閥可參照本部分。
2 規(guī)范性引用文件
下列文件對(duì)于本文件的應(yīng)用是必不可少的。凡是注日期的引用文件，僅注日期的版本適用于本文件。凡是不注日期的引用文件，其最新版本(包括所有的修改單)適用于本文件。
GB/T 3859.1—2013 半導(dǎo)體變流器 通用要求和電網(wǎng)換相變流器 第1-1部分：基本要求規(guī)范
GB/T 13498 高壓直流輸電術(shù)語(yǔ)
GB/T 16927.1 高壓試驗(yàn)技術(shù) 第1部分：一般定義及試驗(yàn)要求
GB/T 20990.1—2007高壓直流輸電晶閘管閥 第1部分：電氣試驗(yàn)
GB 50150—2006 電氣裝置安裝工程 電氣設(shè)備交接試驗(yàn)標(biāo)準(zhǔn)
IEC/TS 60815-1：2008 污染環(huán)境中所用高壓絕緣子的選擇和尺寸測(cè)定 第1部分：定義、信息和一般原理(Selection dimensioning of high-voltage insulators intended fuse in polluted conditions—Part 1：Definitions，information general principles)
IEC 61803：2011 采用電網(wǎng)換相換流器的高壓直流(HVDC)換流站功率損耗的確定[Determination of power losses in high-voltage direct current (HVDC) converter stations with line-commutated converters]
3 術(shù)語(yǔ)和定義
GB/T 13498界定的以及下列術(shù)語(yǔ)和定義適用于本文件。
3.1
閥 valve
由電力電子器件及輔助部件組成的電氣和機(jī)械聯(lián)合體，能實(shí)現(xiàn)單向或者雙向?qū)ā? 注：目前常用的閥有二極管閥、晶閘管閥、絕緣柵雙極晶體管(IGBT)閥等。
3.2
晶閘管閥 thyristor valve
電力電子器件為晶閘管的閥。
3.3
換流器 converter
能實(shí)現(xiàn)完整換流功能的電氣裝置。
3.4
單閥 single valve
由若干個(gè)晶閘管級(jí)串聯(lián)組成，是6脈波換流器的一個(gè)臂。
3.5
晶閘管級(jí) thyristor level
閥的部件，由一個(gè)晶閘管或若干并聯(lián)的晶閘管與緊靠它們的輔助設(shè)備構(gòu)成。
3.6
閥電子電路 valve electronics
在閥電位上執(zhí)行控制、監(jiān)測(cè)和保護(hù)功能的電子電路。
3.7
閥基電子單元 valve base electronics
提供地電位控制設(shè)備與閥電子電路或閥裝置之間接口的電子設(shè)備，又稱(chēng)閥接口電子設(shè)備。
3.8
觸發(fā)角 firing angle
從理想正弦換相電壓正向過(guò)零點(diǎn)至正向電流導(dǎo)通開(kāi)始時(shí)刻的時(shí)間，以電角度度量。
3.9
額定直流電流 rated direct current
按規(guī)定的負(fù)載條件和使用條件，換流器輸出的直流電流(平均值)。
3.10
最大直流電流 maximum direct current
換流器在規(guī)定的運(yùn)行條件下，(理論上可在無(wú)限時(shí)間內(nèi))向負(fù)載輸出的最大直流電流。
注：一般在不同冷卻媒質(zhì)和環(huán)境溫度下有不同值。
3.11
2h過(guò)載直流電流 2h overload direct current
換流器在規(guī)定的2h內(nèi)，能向負(fù)載輸出的直流電流。
注：一般在不同冷卻媒質(zhì)和環(huán)境溫度下有不同值。
3.12
最大理想空載直流電壓 maximum ideal no-load direct voltage
一般指換流器在空載情況下的最大直流電壓(Udi0max)。
注：此時(shí)，將各種電壓降和電網(wǎng)電壓波動(dòng)的因素忽略不計(jì)。
3.13
額定直流電壓 rated direct voltage
在規(guī)定條件下，換流器輸出的直流電壓應(yīng)達(dá)到的平均值。
3.14
額定直流功率 rated direct power
換流器額定直流電壓與額定直流電流之積。
3.15
均流系數(shù) coefficient of current distribution
直流融冰裝置晶閘管閥采用雙橋并聯(lián)型式時(shí)，并聯(lián)運(yùn)行支路電流的平均值與最大支路電流值之比。
3.16
額定結(jié)溫 rated junction temperature
晶閘管正常工作允許的最高結(jié)溫。
3.17
大角度大電流運(yùn)行 large angle and high current operation
直流融冰裝置輸出額定直流電流且觸發(fā)角近似90°的運(yùn)行方式。
3.18
零功率試驗(yàn) zero power test
直流融冰裝置直流側(cè)經(jīng)電抗器短接，將直流電流升至設(shè)定值，檢查直流融冰裝置直流電流控制功能及電流承受能力。
4 技術(shù)要求
4.1 環(huán)境條件
直流融冰裝置晶閘管閥正常使用環(huán)境條件包括以下方面：
a)海拔小于2000m；
b)環(huán)境溫度不低于－20℃，不高于50℃；
c)相對(duì)濕度最大值為85％(20℃以下時(shí))；
d)污穢等級(jí)為b級(jí)；
e)地震震級(jí)，不超過(guò)8級(jí)；
f)交流電網(wǎng)頻率波動(dòng)范圍不超過(guò)±5％。
注1：當(dāng)海拔高度大于2000m時(shí)，應(yīng)根據(jù)相關(guān)標(biāo)準(zhǔn)進(jìn)行海拔修正設(shè)計(jì)。
注2：戶(hù)外污穢等級(jí)，在設(shè)計(jì)時(shí)，一般按照IEC/TS 60815-1：2008中的d級(jí)考慮。
4.2 接入系統(tǒng)
直流融冰裝置換流器宜通過(guò)專(zhuān)用換流變壓器或者換相電抗器接在滿(mǎn)足融冰容量要求的主變壓器低壓側(cè)(10kV或35kV側(cè))，也可與主變壓器低壓側(cè)直接連接。否則，應(yīng)通過(guò)專(zhuān)用變壓器接在上一級(jí)電源母線(xiàn)上。
4.3 負(fù)載性質(zhì)
直流融冰裝置換流器的負(fù)載，主要是不同規(guī)格和不同長(zhǎng)度的架空導(dǎo)線(xiàn)、架空地線(xiàn)、光纖復(fù)合地線(xiàn)(OPGW)、電抗器及其組合。
對(duì)直流融冰兼靜止無(wú)功補(bǔ)償裝置換流器，在靜止無(wú)功補(bǔ)償模式下為三相交流電壓控制電路，負(fù)載為電抗器。
4.4 功能要求
4.4.1 輸出直流電流的范圍
直流融冰裝置換流器輸出的直流電流，在穩(wěn)定運(yùn)行時(shí)，允許選擇從設(shè)計(jì)要求最小值到最大電流之間的任意電流值。
4.4.2 輸出直流電流的偏差
直流融冰裝置換流器輸出的直流電流，在穩(wěn)定運(yùn)行時(shí)，其輸出電流的偏差應(yīng)在目標(biāo)設(shè)定值的±5％以?xún)?nèi)。
4.4.3 輸出直流電壓的要求
直流融冰裝置換流器輸出的直流電壓應(yīng)滿(mǎn)足設(shè)計(jì)要求。
4.4.4 輸出電流的斷續(xù)要求
在電流較小的情況下，直流融冰裝置晶閘管閥的輸出電流可能出現(xiàn)斷續(xù)的情況。如果每周波電流斷續(xù)的次數(shù)少于6次，晶閘管閥應(yīng)能短時(shí)間運(yùn)行(至少10min)。一般情況下應(yīng)加裝平波電抗器以保證零功率試驗(yàn)和架空地線(xiàn)(或光纖復(fù)合地線(xiàn)OPGW)融冰等工況下的電流連續(xù)。
4.4.5 大角度大電流運(yùn)行的要求
直流融冰裝置晶閘管閥應(yīng)允許在大電流大角度方式下持續(xù)穩(wěn)定運(yùn)行。在輸出直流電流達(dá)到額定電流，觸發(fā)角度近似90°的工況下，連續(xù)運(yùn)行時(shí)間大于2h。
4.4.6 工作于靜止無(wú)功補(bǔ)償模式的要求
對(duì)直流融冰兼靜止無(wú)功補(bǔ)償裝置，晶閘管閥需要滿(mǎn)足直流融冰和靜止無(wú)功補(bǔ)償兩種運(yùn)行模式的要求。
5 晶閘管閥的電氣聯(lián)結(jié)型式
直流融冰裝置晶閘管閥的電氣聯(lián)結(jié)型式為6脈波換流器或12脈波換流器。12脈波換流器由兩組6脈波換流器串聯(lián)或者并聯(lián)組成。6脈波換流器每相的臂稱(chēng)為單閥。
為了滿(mǎn)足電能質(zhì)量的要求，減少直流融冰裝置運(yùn)行對(duì)供電系統(tǒng)的影響，在將兩組6脈波換流器串聯(lián)或并聯(lián)時(shí)，閥側(cè)繞組間的相位(角)差應(yīng)為30°，以構(gòu)成12脈波換流器。
6脈波換流器如圖1所示，兩組6脈波換流器串聯(lián)構(gòu)成的12脈波換流器如圖2a)所示，兩組6脈波換流器并聯(lián)構(gòu)成的12脈波換流器如圖2b)所示。
