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GB 311.1-2012: [GB/T 311.1-2012] Insulation co-ordination -- Part 1: Definitions, principles and rules
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[GB/T 311.1-2012] Insulation co-ordination -- Part 1: Definitions, principles and rules
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Insulation co-ordination for high voltage transmission and distribution equipment
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Insulation co-ordination for high voltage transmission and transformation equipments
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Basic data | Standard ID | GB 311.1-2012 (GB311.1-2012) | | Description (Translated English) | [GB/T 311.1-2012] Insulation co-ordination -- Part 1: Definitions, principles and rules | | Sector / Industry | National Standard | | Classification of Chinese Standard | K40 | | Classification of International Standard | 29.020 | | Word Count Estimation | 32,341 | | Older Standard (superseded by this standard) | GB 311.1-1997 | | Quoted Standard | GB/T 311.2; GB/T 2900.19-1994; GB/T 11022; GB 11032; GB/T 16927.1; GB/T 26218.1; IEC 60060-1-2010; IEC 60071-2; IEC 60721-2-3 | | Adopted Standard | IEC 60071-1-2006, MOD | | Regulation (derived from) | National Standards Bulletin No. 13 of 2012 | | Issuing agency(ies) | General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China | | Summary | This Chinese standard provides three-phase AC system voltage power transmission equipment and facilities are relatively insulated, interphase insulation and vertical insulation rated withstand voltage selection principle that these devices standard rated | GB 311.1-2012: [GB/T 311.1-2012] Insulation co-ordination -- Part 1: Definitions, principles and rules
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Insulation co-ordination.Part 1. Definitions, principles and rules
ICS 29.020
K40
National Standards of People's Republic of China
Replacing GB 311.1-1997
Insulation coordination Part 1. Definitions, principles and rules
(IEC 60071-1.2006, MOD)
Published 2012-06-29
2013-05-01 implementation
Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
Standardization Administration of China issued
Table of Contents
Preface Ⅰ
1 Scope 1
2 Normative References 1
Normal and special conditions 3 2
Terms and definitions 4 2
5 9 Symbols and abbreviations
6 with the insulation 10
Withstand voltage test of claim 7 20
Air gap Annex A (normative) to ensure a predetermined impulse withstand voltage of 23
Annex B (normative) altitude correction factor 26
Foreword
All technical content in this section are mandatory, the rest are recommended.
GB 311 "Insulation coordination" is divided into four parts.
--- Part 1. Definitions, principles and rules;
--- Part 2. insulated high voltage transmission and distribution equipment using guidelines;
--- Part 3. HVDC station with an insulating program;
--- Part 4. Calculation conductive network is simulated and the insulation coordination.
This part is the first part of 1 GB 311.
This section drafted in accordance with the rules GB/T 1.1-2009 given.
This section modify using IEC 60071-1.2006 and IEC 60071-1Aml.2010 "Insulation coordination - Part 1. Definitions, principles and rules
then".
This section is GB 311.1-1997. Revision "Insulation coordination Part 1 definitions, principles and rules" of.
This section compared with GB 311.1-1997, in addition to editorial changes Technical changes are as follows.
--- an increase of related terms (see Chapter 4);
--- shows the principle of determining the program and relevant voltage insulation coordination (see 6.2, FIG. 1);
--- shows representative over-voltage waveform and parameters (see 6.3);
--- to increase the insulation level Um 1100kV and 800kV power transmission apparatus (see Table 3);
--- increased Appendix A. to ensure the withstand voltage air gap of a predetermined impact;
--- Added Appendix B. altitude correction factor, the adoption of IEC 60071-2 formulas and curves.
This part of IEC 60071-1.2006 and 60071-1Aml IEC .2010 main differences are as follows.
--- according to the provisions of GB/T 1.1-2009, the standard language and presentation format has been modified;
--- deleted international standards foreword, preface adds this standard;
--- IEC 60071-1 frequency range of 48Hz ~ 62Hz, 60Hz to take into account China's power grid does not apply, it will be set at a frequency range
45Hz ~ 55Hz, so as to conform to the GB/T 16927.1 (see 4.18.1);
--- addition to the standard part of the standard rated withstand voltage value series (see 6.7, 6.8);
--- standard insulation level adjustment (see Table 2, Table 3);
--- increases the different types of power transmission equipment rated withstand voltage (see Table 4, Table 5 and Table 6).
--- When standard impulse withstand voltage test apparatus for non-self-restoring insulation and Recovery insulating coexist, preferred GB/T 16927.1
The withstand voltage test procedure B (see 7.3).
--- Added Appendix B. altitude correction factor, the adoption of IEC 60071-2 formulas and curves.
This portion of the main differences between the terms of the above-described according to IEC 60071-1 by a single vertical line has its outer margin position (|)
It was marked.
This partial replacement GB 311.1-1997 "Insulation coordination Part 1. Definitions, principles and rules."
This section was proposed by China Electrical Equipment Industrial Association.
This part of the National Standardization Technical Committee and the high voltage insulation test technique with (SAC/TC163) centralized.
This section is drafted. Xi'an High Voltage Apparatus Research Institute, State Grid Electric Power Research Institute.
Participated in the drafting of this section. Kunming Electric Apparatus Research Institute, China Electric Power Research Institute switches, Henan high level of electrical Co.,
Company, Baoding Tianwei Electric Co., Shandong Electric Power Research Institute, Research Institute pilot power Hunan, PTD intermediate pressure portion, Shaanxi
Western Power Research Institute, the National Insulator arrester Quality Supervision and Inspection Center, Sunrise Holdings Limited, Huayi Electric Group Co., Ltd., Cooper Nature
(Ningbo) Electric Co., Ltd., Guangzhou Baiyun Electric Equipment Co., Ltd., China Southern Power Grid Technology Research Center, the Jiangxi Provincial Power scientific research
Hospital, School of Electrical Engineering, Xi'an Jiaotong University, Hangzhou Electric Co., open, Shenyang Transformer Research Institute, Hubei Electric Power Test & Research Institute, Shenzhen
Institute of Electrical Science.
The main drafters of this section. Wang Jiansheng, given Xie Valley, Choi Dong, Zhou Peihong, Jia Tao, Guo Jie, Li Shicheng, Dai Min, He Huiwen, Huo Feng.
This part of the drafters participate. Wang Ting, Zhao Lei, Zhou Qiongfang, Kong Xiangjun, Yan Guan Xing, Zhang Jianxin, Zhang joy, Guo Zhihong, Zhou Weihua, Zhang Deqin,
Zhang Peng, Peng Wei, Shi Weijian, Pan Yongcheng, I wish the store spring, Liu Cheng school, Yang Chengmao, Lu Jin Zhuang, Cai Hansheng, Cui Jin Ling, Tong morale, Guo Jie, Zhou Hongdong,
Li Shicheng, Deng Wanting, Lin Zhiwei, Deng Yonghui, Xiaomin Ying.
This section replaces the following previously issued as follows.
--- GB 311-1964, GB 311.1-1983, GB 311.1-1997.
Insulation coordination Part 1. Definitions, principles and rules
1 Scope
This section provides a relatively high voltage transmission equipment and facilities insulated three-phase AC system, and the vertical phase insulation insulation rated
Selection principle withstand voltage, the predetermined standard rated withstand voltage of these devices, and is given a series of standard rated withstand voltage, rated
On principle withstand voltage should be selected from the series.
This section applies to the nominal voltage of more than 1kV three-phase AC system.
Select the rated withstand voltage should be associated with the highest voltage of the device. The association is only for the purpose of insulation fit. This section does not
Including requirements for personnel safety.
This principle also applies to the insulating part with the transmission line, but the withstand voltage value can be a predetermined portion of the present standard rated withstand
Different voltages.
Standards in the development of various devices, should be based on the requirements of this section, adapted to a predetermined rated withstand voltage of such equipment and test procedures.
NOTE. To clarify the rules given in this insulating fitted in GB/T 311.2 "Guidelines for the Use", the highest voltage device and especially standard rated withstand voltage
The relationship between. If the same device sets a voltage corresponding to the highest standard rated withstand voltage, given a set of criteria to select the best rated withstand voltage
The guidelines.
1.1 Scope
This section applies to the highest voltage device above 1kV three-phase AC power system used in the following power transmission indoors and outdoors
equipment.
a) Transformer. power transformers, shunt reactors, current limiting reactors, Petersen coil and the electromagnetic voltage transformer, current transformer;
b) high-voltage electrical categories. circuit breaker, disconnecting switch, a load switch, earth switch, fuse, prefabricated substation, closed switch to
Preparation, enclosed switchgear, a combination of electrical appliances;
c) power capacitors, the coupling capacitor (capacitor voltage transformer comprising a), shunt capacitor, AC filter capacitor;
d) high-voltage power cable;
e) post insulators, wall bushing and the like.
1.2 NA range
a) mounted on the insulation with severe contamination or harmful gases, vapors, chemical equipment in case of deposits;
b) Relative humidity is high and condensation prone indoor applications device.
2 Normative references
The following documents for the application of this document is essential. For dated references, only applies to the version dated paper
Pieces. For undated references, the latest edition (including any amendments) applies to this document.
GB/T 311.2 Insulation coordination Part 2. insulated high voltage transmission and distribution equipment using the guidelines (IEC 60071-2.1996,
EQV)
GB/T 2900.19-1994 technical Electrotechnical term high voltage test and insulation coordination (IEC 60071-1.1993, NEQ)
GB/T 11022 common technical requirements voltage switchgear and control equipment standard (GB/T 11022-2011, IEC 62271-1.
2007, MOD)
GB 11032 no AC MOA (GB 11032-2010, IEC 60099-4.2006, MOD)
GB/T 16927.1 High Voltage Test Techniques - Part 1. General test requirements (GB/T 16927.1-2011, IEC 60060-1.
2010, MOD)
Selection and dimensioning of GB/T high-voltage insulators for use under condition determining contamination 26218.1 Part 1. Definitions, general information, and
Principles (GB/T 26218.1-2010, IEC /T S60815-1.2008, MOD)
IEC 60060-1.2010 High Voltage Test Techniques - Part 1. General Definitions and test requirements (High-voltagetesttech-
niques-Part 1. Generaldefinitionsandtestrequirements)
Insulation coordination IEC 60071-2Am1Ed.3.0 Part 2. Application guide (Insulationco-ordination-Part 2.
Applicationguide)
Part IEC 60721-2-3 Classification of environmental conditions 2. Natural Environment Section 3. Pressure (Classificationofenvi-
ronmentalconditions-Part 2-3. Environmentalconditionsappearinginnature-Airpressure)
Normal and special conditions 3
3.1 normal environmental conditions
Withstand voltage selected from Table 2 and Table 3 below normal environmental conditions.
a) ambient air temperature does not exceed 40 ℃ and measured to 24h average does not exceed 35 ℃. Minimum ambient air temperature is divided into three
Level. -10 ℃, -25 ℃ and -40 deg.] C;
b) altitude does not exceed 1000m;
c) ambient air is not significantly dust, smoke, corrosive gases, vapors or salt contamination. Filthy filthy grade level does not exceed C
(See GB/T 26218.1);
d) condensation and deposition typically occurs. Consider the sediment appears to dew, condensation, fog, rain, snow or frost forms.
3.2 standard reference atmospheric conditions
Standardized withstand voltage applicable to the standard reference atmospheric conditions.
a) Temperature. t0 = 20 ℃;
b) Pressure. p0 = 101.3kPa (1013mbar);
c) Absolute humidity. h0 = 11g/m3.
3.3 Special environmental conditions
3.3.1 Test Voltage ambient air temperature is higher than 40 ℃ apparatus, the outer insulation in the dry state should take this nominal section
Withstand voltage value is multiplied by the temperature correction factor KT.
KT = 1 0.0033T (-40)
Where.
T --- ambient air temperature, ℃.
3.3.2 For altitudes above 1000m, 4000m, but the device does not exceed the dielectric strength of the insulation shall be outer altitude correction, the correction
See Appendix B.
3.4 grounding equipment for power system neutral point
The highest voltage 126kV active or non-effectively grounded system (direct) grounding system; maximum voltage of 126kV and above should have
Effect (direct) grounding system.
Terms and definitions 4
The following terms and definitions apply to this document.
4.1
Insulation coordination insulationco-ordination
After considering over-voltage protection measures adopted, the decision on the possible role of voltage equipment, and insulation and may affect the characteristics of the device according to
Factors insulation properties, dielectric strength equipment to determine the reasonableness of the security operation and technical and economic aspects.
[Modification GB/T 2900.19-1994, definitions 3.23]
Note. "dielectric strength" refers to a device rated insulation level or standard insulation level by 4.35 and 4.36, respectively defined.
4.2
External insulation externalinsulation
Solid insulation exposed in the atmosphere in the air gap and the surface equipment, it is subjected to the applied voltage and by the external atmospheric conditions, and the other field,
Effects such as contamination, humidity, and other pests.
[GB/T 2900.19-1994, definitions 3.24]
NOTE. insulating outer weather protective or may be a non-climate protection, are designed to run inside or outside the protective body.
4.3
Insulating internalinsulation
Solid, liquid or gas unaffected by atmospheric conditions other external equipment insulation.
[GB/T 2900.19-1994, definitions 3.25]
4.4
Self-restoring insulation self-restoringinsulation
After disruptive discharges during the test, after a short time, it can be fully restored the insulating properties of the insulation.
[Modification GB/T 2900.19-1994, definitions 3.28]
Note. These are generally insulated external insulation, but is not required.
4.5
Non-self-restoring insulation nonself-restoringinsulation
After disruptive discharges during the test, or not fully recover the loss of insulation properties of the insulation.
[GB/T 2900.19-1994, definitions 3.29]
NOTE. 4.4 and 4.5 is defined only by the action of the test applies the discharge voltage during the insulation test caused. However, discharge may be caused at runtime
Since self-restoring insulation partial or complete loss of its original insulating properties.
4.6
Terminal insulating structure insulationconfigurationterminal
Voltage may be applied to any of the terminals between any two terminals on the insulation. Terminals are.
a) phase terminal. the terminal is applied to neutral voltage of the system between its neutral point and the run-time;
b) neutral point terminal. equivalent to the system neutral point or neutral point terminal (neutral terminal of the transformer and the like);
c) ground terminal. In operation, the ground terminal is always fixed (the transformer housing, the base of the disconnector, the tower frame, ground
Plate or the like).
4.7
Insulating structure insulationconfiguration
Complete geometry and operation of all of the contacts by an insulator composed of insulating. It includes all of the elements (electrical insulating properties of the dielectric effect
Edge member and the conductive member). Insulating structure is divided into the following categories.
4.7.1
Three-phase insulating structure three-phaseinsulationconfiguration
Having three phase terminals, a neutral terminal structure and a ground terminal.
4.7.2
Relatively (PE) insulation phase-to-earth (pe) insulationconfiguration
Excluding the two phase terminals of a three phase insulating structure, and except in special circumstances, neutral terminal is grounded.
4.7.3
Phase (pp) insulation phase-to-phase (pp) insulationconfiguration
Excluding a three-phase insulating structure of a phase terminal. In special cases, neutral and ground terminals negligible.
4.7.4.
Longitudinal (TT) insulation longitudinal (tt) insulationconfiguration
With two phase terminal and a ground terminal of the insulating structure. (Two) phase terminals belonging to the same phase of the three-phase system, which is temporarily
Divided into two separate charging portion (e.g., opening the switch means). Belonging to the other two phases excluding the four terminals or ground. Special
Case, that one of the two phase terminals is grounded.
4.8
The nominal system voltage nominalvoltageofasystem
Un
Or represents a recognition system for a suitable voltage value is approximated.
[GB/T 2900.19-1994, defined 2.4]
4.9
Maximum system voltage highestvoltageofasystem
Us
Under normal operating conditions, the system at any point in any of the effective value of the maximum operating voltage of a timing phase occurring.
[Modification GB/T 2900.19-1994, defined 2.5]
4.10
Highest voltage for equipment highestvoltageforequipment
Um
The apparatus insulating properties as well as other related standards associated equipment designed highest voltage RMS phase. In normal
Under operating conditions specified by the relevant Technical Committee, the voltage can be continuously applied to the device.
[Modification GB/T 2900.19-1994, defined 2.7]
4.11
Neutral insulation system isolatedneutralsystem
In addition to protected, high-impedance ground measurement, the ungrounded system.
[GB/T 2900.19-1994, definitions 3.13]
4.12
Fixed neutral grounding system solidlyearthedneutralsystem
Directly grounded neutral system.
[Modification GB/T 2900.19-1994, definitions 3.14]
4.13
(Neutral) impedance grounding system impedanceearthed (neutral) system
To limit the ground fault current, the impedance grounded neutral system.
[Modification GB/T 2900.19-1994, definitions 3.16]
4.14
(Neutral) resonant grounding system resonantearthed (neutral) system
One or more neutral grounding through the reactor system, the reactor is approximately single-phase ground fault current compensating capacitive component. neutral
Compensation point can be approximated by single-phase ground fault current component of the capacitive reactance of the grounding system.
[Modification GB/T 2900.19-1994, definitions 3.15]
Note. the resonance grounding system flowing through the fault point current is limited to the extent that residual air can be generally self-extinguishing arc of a ground fault.
4.15
Ground fault factor earthfaultfactor
In a given system configuration of a three-phase system given point, during any failure of the system has little influence one or more phases, Jian
When all phases working relatively highest frequency voltage effective value of the point is relatively fault-free RMS voltage frequency ratio.
[GB/T 2900.19-1994, definitions 3.17]
4.16
Overvoltage overvoltage
In a three-phase system voltage Us is the highest, the peak value exceeds the maximum system voltage peak opposite (Us × 2/3) or maximum interphase
Or any relative phase to phase voltage waveforms of the peak pressure (2uS) respectively opposite phase or overvoltage.
When the overvoltage value expressed in unit value, contrast, and white over the reference value of the voltage Us × 2/3, respectively and 2uS (in pu
Representation).
[Modification GB/T 2900.19-1994, Definitions 3.1]
NOTE. Unless expressly stated otherwise, for example, surge arresters usually PU overvoltage value (equal Us × 2/3). FIG.
4.17
Voltage and over-voltage classification classificationofvoltageandovervoltage
Waveform and its duration, and overvoltage can be divided into the following.
Note. in Table 1 given below about 6 and overvoltage conditions more detail.
4.17.1
Length (frequency) voltage continuous (powerfrequency) voltage
Rms has a stable, sustained action working on either one of the pair of terminal insulation frequency voltage.
4.17.2
Temporary overvoltage temporaryovervoltage; TOV
Longer duration power frequency overvoltage.
[Modification GB/T 2900.19-1994, defined 3.6]
NOTE. overvoltage may be undamped or weakly damped. In some cases, the frequency may be several times lower than the frequency or several times.
4.17.3
Transient overvoltage transientovervoltage
A few milliseconds or less in duration over-voltage, typically high damping oscillation or oscillations.
[GB/T 2900.19-1994, defined 3.7]
Note. The temporary overvoltage transient overvoltage appears likely to follow, in this case, consider these two overvoltage are two separate processes.
Transient over-voltage is divided into the following categories.
4.17.3.1
Overvoltage slow wavefront (operation) slow-frontovervoltage; SFO
One kind of transient overvoltage, typically unidirectional, time to peak is 20μs \u003cTp≤5000μs,而波尾持续时间T2≤
20ms.
4.17.3.2
Fast wave front overvoltage (lightning) fast-frontovervoltage; FFO
One kind of transient overvoltage, typically unidirectional, reaches a peak time of 0.1μs \u003cT1≤20μs,波尾持续时间T2\u003c300μs。
4.17.3.3
Express wavefront overvoltage very-fast-frontovervoltage; VFFO
One kind of transient overvoltage, typically unidirectional, time to peak Tf≤0.1μs, with or without superimposed oscillation, the oscillation frequency
30kHz \u003cf\u003c100MHz之间。
NOTE. Express wavefront also known overvoltage VFFO Laid fast transient overvoltages VFTO (very-fast-transientovervoltage).
4.17.4
United overvoltage combinedovervoltage
In the simultaneous action of phase (or longitudinal) between the two voltages to each terminal and the insulated phase terminals of the two component composition. It was attributed to
Component having a higher peak (temporarily, before the slow waves, and the fast wave front before the wave express) a class.
4.18
Standard test voltage waveform standardvoltageshapesfortest
4.18.1 ~ 4.18.5 voltage waveform has been normalized.
Note. For the following three standard voltage 4.18.1 ~ 4.18.3 More detailed information is given in the GB/T 16927.1 and in Table 1.
4.18.1
Standard short-frequency voltage standardshort-durationpower-frequencyvoltage
It has a frequency between 45Hz ~ 55Hz, duration of the sinusoidal voltage 60s.
NOTE. IEC 60071-1 frequency range of 48Hz ~ 62Hz, 60Hz consideration of the NA of the grid, it will be set to the frequency range 45Hz ~ 55Hz,
To conform to GB/T 16927.1.
4.18.2
Standard operating impulse voltage standardswitchingimpulsevoltage
Having a peak time is 250μs and the half value of the surge voltage 2500μs.
4.18.3
Standard lightning impulse voltage standardlightningimpulsevoltage
Having a wave front time of 1.2μs and a half value of the surge voltage 50μs.
4.18.4
Standard joint operating impulse voltage standardcombinedswitchingimpulsevoltage
For phase insulation, combined with the opposite polarity switching impulse voltage of the two components.
Positive polarity switching impulse voltage is a standard component and the negative component of the peak and half-value time is not less than the positive polarity electric shock
Voltage value corresponding to the operation of the surge voltage. Two impact should reach a peak at the same instant. Thus the peak voltage of these components combined peak
Sum.
4.18.5
Joint standard voltage standardcombinedvoltage
Of vertical insulation, the surge voltage is a combined voltage as a standard terminal, the voltage of the other terminal of the power frequency. Anti-shock is applied to the component
Peak frequency voltage polarity.
4.19
Representative overvoltage representativeovervoltage
Urp
Suppose on the insulation and by generating a runtime due to various reasons given the same kind of over-voltage insulating effect of
Voltage.
They consist of a voltage waveform corresponding category criteria and can represent a value or set of values, or some characteristic of the operating conditions
Values to define the frequency distribution.
Note. This definition also applies to the continuing work indicates the operating voltage frequency voltage insulation effect.
4.20
Overvoltage limiting device overvoltagelimitingdevice
It means the peak voltage or duration or both limits are used to limit too. They can be divided into prevention guard device (e.g., pre-accessible electrical
Resistor) or the protector (arrester).
4.21
Lightning (or operations) impact protection level lightning (orswitching) impulseprotectivelevel; LIPL or SIPL
Upl (or Ups)
Under a predetermined condition, the receiving terminal lightning protection device (or operations) the maximum allowable voltage peak impact.
4.22
Performance indicators performancecriterion
Selecting a reference insulated, so that the probability that the insulating effect of injury or equipment in various types of continuous operation of the device that causes the voltage
Reduced to an acceptable level the economic and run. Typically, the term pharmaceutically insulation failure rate number (fault year, twice a Symptom
Between the years, the risk of failure, etc.) to represent the indices.
4.23
Withstand voltage withstandvoltage
When the test voltage is applied to pressure test under specified conditions. During the pressure test allowed the predetermined disruptive discharge
frequency. Withstand voltage.
a) conventional withstand voltage setting. At this time, the number of discharges allows a disruptive zero, i.e. tolerability probability Pw = 100%.
b) statistical withstand voltage. Almost tolerance permitted tolerance disruptive discharge probability with a predetermined number of times related to this predetermined section
Ratio Pw = 90%.
Note. In this section, a non-self-restoring insulation by setting a predetermined withstand voltage customary; while a predetermined statistical self-restor...
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