What is the difference between power transformer GB1094 and iec60076 standard?
Writer： Hengfeng you electric Time：2023-04-14 views：times
Differences between gb1094.1 and iec60076-1 standards
1、 Operate under unstable conditions above rated voltage and / or frequency
Gb1094.1-1996 (equivalent iec76-1-1993): page 8, for special use cases, under the rated frequency, the user can specify that the transformer shall be operated at the rated voltage higher than 105% but not more than 110%. If there are no special requirements for the relationship between current and voltage, when the current is K (0 ≤ K ≤ 1) times the rated current, the voltage u shall be limited according to the following formula. U(%)=110-5K。
Iec60076-1-1993, iec60076-1 ed2.1 2000-04 and iec60076-1 ed3.0 2011: none. The national standard is added according to China's operating conditions.
2、 Terms and definitions
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
Iec60076-1 ed3.0 2011: P19 added definitions of off excitation tap changer, maximum allowable tap working voltage, maximum allowable voltage of equipment and harmonic content.
3、 Ratings and general requirements
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
Iec60076-1 ed3.0 2011: P26 new clauses on transformer transportation.
4、 Requirements for tapping during inquiry and ordering
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
Iec60076-1 ed3.0 2011: P32 added 6.4.3 functional specifications.
5、 Connection group
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
6、 Safety, environmental and other requirements
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
Iec60076-1 ed3.0 2011: p41 ~ p43 added 9. Liquid leaves, safety consideration, dimensioning of neutral connection, liquid preservation system, DC current in neutral circuits.
7、 No load loss and no load current measurement
Gb1094.1-1996: page 17: when three-phase transformer is tested, if D (or y) connection winding is excited, the voltage shall be measured between each phase terminal;
Iec60076-1-1993, iec60076-1 ed2.1 2000-04 and iec60076-1 ed3.0 2011: Y-connection winding is not mentioned in IEC standards.
8、 EMC test
This test item is not specified in gb1094.1-1996 and iec60076-1-1993.
Iec60076-1 ed2.1 2000-04, iec60076-1 ed3.0 2011: Transformers shall be regarded as passive components in terms of emission and anti electromagnetic interference
9、 Appendix A
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: none.
Iec60076-1 ed3.0 2011: the information list to be checked during inquiry and ordering has been added and becomes the information list.
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: there is no such test item in routine test, which is required in GB / T 6451.
Iec60076-1 ed3.0 2011: this item is added to routine test items on page P46, g) leak testing with pressure for liquid immersed transformers (tightness test); Pressure leakage test of oil immersed transformer.
On page p51, the sealing test shall be conducted according to the supply agreement. If there is no provision, the pressure of at least 30KPa shall be applied to the transformer of 20MVA or 72.5kV for 24h, and the pressure of the transformer of lower capacity or voltage level shall be applied for 8h. Especially for the oil tank designed to adapt to oil expansion (usually corrugated) with its own elasticity, the leakage and life test shall be in accordance with the provisions of the agreement.
11、 Sealing and pressure test of inflatable transformer box
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: there is no such test item in routine test.
Iec60076-1 ed3.0 2011: this item is added to routine test items on page P46 h) tightness tests and pressure for tanks for tanks for gas filled transformers; (refer to iec60076-15 power transformers - Part 15: gas filled power transformers).
12、 Check the transformation ratio and polarity of the built-in current transformer
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: there is no such test item in routine test.
Iec60076-1 ed3.0 2011: this item is added to routine test items on page P46, I) check of the ratio and polarity of build in current transformers.
13、 Check the insulation of oil immersed transformer core and support structure
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: there is no such test item in routine test.
Iec60076-1 ed3.0 2011: this item is added to routine test items on pages P46 and p53, J) check of core and frame insulation for liquid embedded transformers with core or frame insulation; And 11.12, for the grounding condition of the iron core and support structure of the oil transformer after oil injection, before the live parts are loaded into the oil tank, apply DC500v without flashover for 1min to verify the insulation. For the oil transformer, the grounding of the iron core and supporting structure can be seen after oil injection. After oil injection of the transformer, apply dc2500v without flashover for 1min to verify the insulation
14、 Additional routine test for transformers with maximum equipment voltage > 72.5kV
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: there is no such test item in routine test.
Iec60076-1 ed3.0 2011: this item is added to routine test items on page P46, including a) measurement of winding to ground and capacitance between windings; b) Measure the insulation resistance of each winding to ground and between windings to ground; c) Dielectric loss factor of insulation system capacitance (tan) δ） Measurement of dissolved gases in dielectric liquid from each separate oil component except diverter switch component; E) measurement of no-load loss and no-load current at 90% and 110% rated voltage.
15、 Sound level measurement
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: sound level measurement is a special test item.
Iec60076-1 ed3.0 2011: P47 sound level measurement is a type test item. Measure the sound level under each cooling mode.
16、 Measurement of power absorbed by fan and oil pump
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: this item is a special test item.
Iec60076-1 ed3.0 2011: P47 this item belongs to type test item.
17、 Measurement of no-load loss and no-load current at 90% and 110% rated voltage
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47 added this item as a type test item.
18、 . dielectric loss factor (tan) of winding to ground insulation resistance and / or insulation system capacitance δ） Measurement of
Gb1094.1-1996: page 16, e. dielectric loss factor (tan) of winding to ground insulation resistance and / or insulation system capacitance δ） The measurement of is routine test.
Iec60076-1-1993, iec60076-1 ed2.1 2000-04 and iec60076-1 ed3.0 2011:. This item is a special test item.
19、 Insulating oil test
Gb1094.1-1996: page 16, H. insulating oil test is routine test.
Iec60076-1-1993, iec60076-1 ed2.1 2000-04 and iec60076-1 ed3.0 2011: insulation oil test is not specified in the standard.
20、 No load current harmonic measurement
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no load current harmonic measurement belongs to special test items.
Iec60076-1 ed3.0 2011: P47, there is no requirement for no-load current harmonic measurement in the standard.
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, new item, special test.
22、 Vacuum disturbance deformation test of oil immersed transformer
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: page P47 and page p51 11.9 vacuum deflection test for liquid immersed transformers, a new item, belong to special test. This test item is applicable to transformers whose oil tank is vacuumized at the installation site. These transformers are not injected with insulating liquid during transportation. Measure the deformation of oil tank after vacuumization and the permanent deformation of oil tank after vacuumization 。
23、 Pressure disturbance deformation test of oil immersed transformer
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: page P47 and page p52, 11.10 pressure deflection test for liquid immersed transformers increases the positive voltage immunity test of oil immersed transformers. In particular, it is designed to adapt to the expansion of oil (usually corrugated type) with its own elasticity When there are special requirements, apply pressure to the oil tank to detect deformation and release the pressure to detect permanent deformation of the oil tank.
The test shall be carried out after all groups of transformer components are filled with oil, and the test shall be carried out on all independent oil filled components.
Unless otherwise specified, the test pressure of the oil tank is 35kpa. If the oil tank is equipped with a pressure relief device, the test pressure shall be at least 10KPA greater than the pressure required for operating the pressure relief device, and the pressure relief device shall be blocked during the test.
24、 Field vacuum sealing test of oil transformer
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: page P47 and page p52, 11.11 vacuum tightness test on site for liquid
This test is applicable to transformers that do not inject oil during transportation and vacuum oil the oil tank on site. According to the required value of field operation, vacuum the oil tank for two hours or until a stable vacuum value is obtained, stop the vacuum pump and seal the transformer. Monitor the vacuum in the transformer with a vacuum gauge until it is observed that the vacuum changes at a steady rate. The increase rate of vacuum pressure shall be less than 0.2kpa/h within a period of at least 30min
25、 Measurement of frequency response
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, new item, special test. Frequency response analysis or FRA, the test procedure shall be in accordance with the agreement between the manufacturer and the user. No specific test method and judgment basis are specified.
26、 Inspection of outer coating
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, added in special test items. (ISO 2178 and ISO 2409 or as specified).
27、 Measurement of dissolved gas in insulating oil
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, added in special test items. No specific test method and judgment basis are specified.
28、 Mechanical test or evaluation of tank suitability for transportation (according to user requirements)
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, added in special test items. No specific test method and judgment basis are specified.
29、 Measure the transport weight of the transformer
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, added in special test items. Transformers up to 1.6mva are determined by measurement. For larger transformers, the transport weight can be measured or calculated according to the agreement between the manufacturer and the user.
30、 Transient overvoltage of high frequency switch
Gb1094.1-1996, iec60076-1-1993, iec60076-1 ed2.1 2000-04: no requirements.
Iec60076-1 ed3.0 2011: P47, added in special test items. Light load switch with vacuum or SF6 circuit breaker and / or low power factor (inductive load) transformer may cause the transformer to be damaged by MHz high-frequency overvoltage, and the voltage exceeds the impact withstand capacity of the transformer. Mitigation measures include: increasing damping through resistance capacitor, input impedance, etc.
Differences between gb1094.2 and iec60076-2 standards：
1、 The scope of application of the standard is different:
Gb1094.2-1996 (equivalent to iec76-2-1993): applicable to power transformers specified in gb1094.1 (both dry transformer and oil transformer are applicable).
Iec60076-2-1993: applicable to power transformers specified in gb1094.1 (both dry transformer and oil transformer are applicable).
Iec60076-2-2011: applicable to oil immersed transformer;
Gb1094.2-1996 (equivalent iec76-2-1993): page 3, top oil temperature rise: 60K for transformers whose oil is not in direct contact with the atmosphere and 55k for transformers whose oil is in direct contact with the atmosphere; The average temperature rise of winding is 65K.
Iec60076-2-1993 top oil temperature rise: 60K; Average winding temperature rise: 65K for transformers marked on or of and 70K for transformers marked OD.
Iec60076-2-2011 top oil temperature rise: 60K; Average winding temperature rise: 65K for transformers with on or of mark and 70K for transformers with OD mark; Winding hot spot temperature rise: 78k (special test, only applicable to transformers with rated capacity of 20 / 3 MVA / phase and above);
3、 Oil temperature rise above ambient temperature multiplied by correction factor:
GB1094.2-1996： ，x=1.0 ； For transformers with on or of cooling mode. Translation errors.
Iec60076-2-1993 and iec60076-2-2011: x = 1.0 for transformers with of or od cooling mode.
4、 For air-cooled transformers, when the temperature at the installation site exceeds the ambient temperature specified in 1094.1 (i.e. the average temperature in the hottest month does not exceed + 30 ℃, the annual average temperature does not exceed + 20 ℃, and the maximum temperature does not exceed + 40 ℃):
Gb1094.2-1996 and iec60076-2-1993: page 3 of GB, if the temperature of the installation site exceeds the ambient temperature specified in 1094.1, the temperature rise limit of the transformer shall be reduced according to the value of the excess part and rounded to the integer value closest to the temperature. However, the specific rounding off value is not given in the standard.
Iec60076-2-2011: Table 2 on page 12 gives the specific rounding off method when the temperature of the installation site exceeds the specified ambient temperature.
5、 Measurement of ambient temperature in temperature rise test
Gb1094.2-1996 and iec60076-2-1993: page 4 of GB, there shall be at least three temperature sensors for the measurement of ambient temperature in the test, and the test shall be evaluated by its average value. Distributed around the oil tank, 1 ~ 2m away from the oil tank or cooler; For air-cooled transformer, the position of temperature sensor shall be able to display the actual air temperature of cooler, and attention shall be paid to air recirculation.
Iec60076-2-2011: Page 13, there shall be at least 4 temperature sensors for the measurement of ambient temperature in the test, and the test shall be evaluated by its average value. It is distributed around the oil tank, about 2m away from the oil tank or cooler. For air-cooled transformers, the sensor shall be placed in the air 0.5m away from the vent.
6、 Test method for oil temperature rise:
Gb1094.2-1996 and iec60076-2-1993: page 5 of GB, after the top oil temperature rise is measured, immediately reduce the test current in the winding to the rated current and continue the test for 1H.
Iec60076-2-2011: page 15: after the top oil temperature rise is measured, immediately reduce the test current in the winding to the rated current and continue the test for 1H. During this process, the top oil temperature, winding hot spot temperature (if measured) and external cooling medium temperature shall be continuously recorded at least every 5min. However, the average temperature within 1h is not taken in the standard.
7、 Measurement of top oil temperature rise, average oil temperature rise and bottom oil temperature rise
Gb1094.2-1996 and iec60076-2-1993: page 6 of GB, the standard only gives the measurement method of top oil, average oil and bottom oil temperature, and does not specify the measurement method of temperature rise.
Iec60076-2-2011: page 18, the standard specifies not only the measurement method of top oil, average oil and bottom oil temperature, but also the specific measurement and calculation method of temperature rise. (Note: the oil temperature is the average of the readings in the last hour of the total loss stage.)
8、 Measure the difference between the average winding temperature and the oil temperature
Gb1094.2-1996 and iec60076-2-1993: not required in the standard.
Iec60076-2-2011: 7.9 on page 19, the standard requires to measure the difference between uncorrected winding average temperature and average oil temperature when cutting off the power supply.
9、 Measurement of hot spot temperature rise of winding
Gb1094.2-1996 and iec60076-2-1993: not required in the standard.
Iec60076-2-2011: 7.10 on page 20 specifies the specific measurement and calculation method of winding hot spot temperature rise.
10、 Uncertainty affecting temperature rise test results
Gb1094.2-1996 and iec60076-2-1993: not required in the standard.
Iec60076-2-2011: 7.11 on page 20, the standard requires that the uncertainty affecting the temperature rise test results be given in the test report.
11、 Analysis of dissolved gas in oil
Gb1094.2-1996 and iec60076-2-1993: not required in the standard.
Iec60076-2-2011: 7.12 on page 20, for large capacity oil transformer, it shall be negotiated between the manufacturer and the user as a special test, and the dissolved gas in the oil shall be analyzed before and after the temperature rise test. See Appendix D for specific methods.
12、 Test method for temperature rise test of oil immersed transformer
Gb1094.2-1996 and iec60076-2-1993: not required in the standard.
Iec60076-2-2011: Appendix C on page 31 stipulates that for transformers with capacity < 100mva, the time from disconnecting the power supply to obtaining the first effective hot state resistance measurement value shall not exceed 2min. (since it takes a period of time for the current to stabilize, there is an inductive voltage drop in the winding, so the reading reliability at the beginning of measurement is relatively poor).
Differences between gb1094.3 and iec60076-3 standards
1、 Maximum voltage and insulation level of equipment
Gb1094.3-2003 (equivalent iec60076-3:2000): page 3, if one winding is graded insulation, the UM value of neutral terminal and its insulation level shall be in accordance with table 4.
Iec60076-3:2000: Um value and insulation level of neutral point terminal with graded insulation shall be specified by the user.
2、 Requirements and tests for different types of windings
Gb1094.3-2003 (equivalent iec60076-3:2000): page 5, when um ≤ 72.5kV in Table 1, line end full wave (LI), line end cut-off (LIC) and neutral point full wave (LI) are type tests (for fully insulated three-phase transformers, when the neutral point is not led out, the lightning full wave impulse test at the neutral point is a special test), and the long-term induced withstand voltage ACLD test is not applicable
Iec60076-3:2000: when um ≤ 72.5kV, lightning impulse (LI) is type test, and long-term induced withstand voltage ACLD test is not applicable. However, Li test requirements in some countries are routine test, and ACLD test requirements are routine test or type test. Line end truncation (LIC) is a special test.
See Table 1 of gb1094.3-2003 and table 1 of iec60076-3:2000 for requirements and tests of other voltage levels.
3、 Maximum equipment voltage um ≤ 170KV rated withstand voltage of transformer winding
Gb1094.3-2003: page 5, see Table 2 for the full wave and cut-off peak value of rated lightning impulse withstand voltage corresponding to the nominal voltage of different systems and the rated short-time induced or applied withstand voltage.
Iec60076-3:2000: page 27, the classification of system nominal voltage value and corresponding withstand voltage value are different. See Table 2 and table 3 for European standards and North American standards respectively. For example, the applied withstand voltage value of transformer winding with um of 12kV is 35kV in the national standard and 28kv in Table 2 of IEC standard.
4、 Maximum equipment voltage um ＞ 170KV rated withstand voltage of transformer winding
Gb1094.3-2003: see Table 3 on page 5.
Iec60076-3:2000: see Table 4 on page 30 for specific differences.
5、 Insulation requirements
Gb1094.3-2003: page 6, standard applied withstand voltage of neutral terminal: for full insulation, its voltage value is the same as that of line terminal. For rated withstand voltage of neutral terminal of graded insulation transformer, see Table 4
Iec60076-3:2000: the withstand voltage value of neutral terminal is not specified.
6、 Insulation requirements
Gb1094.3-2003: page 6, low voltage winding with um ≤ 1.1kv shall withstand 5kV applied withstand voltage test. Iec60076-3:2000: page 27, low voltage winding with um ≤ 1.1kv shall withstand 3KV applied withstand voltage test.
7、 Insulation test
Gb1094.3-2003: short time induced voltage withstand test (ACSD), determined through negotiation between the manufacturer and the user, partial discharge measurement can also be carried out for transformers with um < 72.5kV and um = 72.5kV and rated capacity less than 10000kva..
Iec60076-3:2000: page 29, IEC standard does not require partial discharge measurement for transformers with um = 72.5kV.
8、 Insulation requirements and insulation test of winding neutral terminal
Gb1094.3-2003: see page 7. Since China's insulation requirements and insulation test for neutral point terminals are different from the provisions of IEC standards, this test shall be modified and supplemented according to China's national conditions.
Iec60076-3:2000: see page 35 for specific tests.
9、 Lightning impulse test (LIC) with wave tail truncation
Gb1094.3-2003: this item is a type test in the national standard. The peak value of chopped impulse withstand voltage is shown in Table 2 or table 3.
Iec60076-3:2000: IEC standard stipulates that the chopped wave shock test is a special test, which shall be carried out under the agreement of both parties. The test shall be conducted in combination with the lightning full wave impulse test according to the following methods, and the peak value of cut-off impulse withstand voltage shall be 1.1 times the peak value of full wave voltage.
10、 External insulation air gap
Gb1094.3-2003: page 18 ~ 19, the national standard specifies the air gap requirements of the live part of the neutral point bushing to the ground, as shown in Table 7. See Table 5 and table 6 for the phase to ground, phase to phase, relative neutral point of the live part of the bushing of power transformer with different voltage levels and the minimum air gap to the low-voltage winding terminal, which is different from the required values in IEC standards.
Iec60076-3:2000: IEC standard does not specify the air gap requirements for the live part of neutral point bushing to the ground. See Table 5 and table 6 for the phase to ground, phase to phase, relative neutral point and the minimum air gap to the low-voltage winding terminal of the live part of the bushing of power transformer with different voltage levels.
Differences between gb1094.5 and iec60076-5 standards：
1、 Maximum voltage and insulation level of equipment
Gb1094.5-2008 (modified by iec60076-5:2006): page 2, considering the specific situation of China's power grid system, the maximum voltage and short-circuit apparent capacity of equipment are listed in Table 1 according to the actual situation of China's power grid of various voltage levels. (consider whether the system short-circuit impedance needs to be added when calculating the short-circuit current.)
Iec60076-5:2006: see Table 2 on page 13 for corresponding provisions.
Differences between gb1094.11 and iec60076-11 standards
1、 Scope of application of the standard
Gb1094.11-2007 (modified by iec60076-11:2004): Page 1, this standard is applicable to dry-type power transformers with maximum equipment voltage of 40.5kV and below and at least one winding operating above 1.1kv.
Iec60076-11:2004: Page 13, this standard is applicable to dry-type power transformers with maximum equipment voltage of 36kV and below and at least one winding operating above 1.1kv.
2、 Nameplate fixed to transformer
Gb1094.11-2007: page 4, same as IEC, note 1 is added to simplify the marking content: when the insulation system temperature of each winding is the same, only one letter can be marked. Note 2: when it is impossible to mark with letters, it can be marked with temperature (Celsius of insulation system temperature).
Iec60076-11:2004: page 23: insulation system temperature of each winding. The first letter represents high-voltage winding and the second letter represents low-voltage winding. When there are multiple windings, the letters shall be arranged in order from high-voltage winding to low-voltage winding.
3、 Insulation level
Gb1094.11-2007: on page 6, the column of system nominal voltage is added in Table 3. The rated short-time withstand voltage of transformer with um of 12kV is 35kV; The insulation level corresponding to the maximum voltage um of 40.5kV is given.
Iec60076-11:2004: Article 29, rated short-time withstand voltage of transformer with um of 12kV is 28kv; Give the insulation level corresponding to the maximum voltage um of the equipment is 36kV.
4、 General requirements for tests
Gb1094.11-2007: page 8, regular type tests shall be conducted at least once every 5 years.
Iec60076-11:2004: not required.
About the relationship between hengfengyou electric and GB and IEC standards:
As an export-oriented enterprise dedicated to the power transformer industry, Qingdao hengfengyou electric mainly implements IEC standards and has many years of experience in transformer manufacturing, testing and after-sales service. Its products have been exported to Spain, France, Zimbabwe, Tanzania, South Africa, Ghana, Ethiopia, Iraq, Kuwait, Uzbekistan, Kazakhstan Vietnam and other more than 30 countries in the world. Hengfengyou electric strictly implements SQA workflow and ISO quality standards to ensure that it provides first-class electrical products and best services to users all over the world. ( info@hengfengyou.com )。 WhatsApp：+86 15853252696（Jack) +86 158 5326 5269（Alisa）
