Some standard content:
National Standard of the People's Republic of China
Circuit-hreaker capacitors
1 Subject content and scope of application
GB/T 4787-1996
Replaces GB4787---84
This standard defines the scope of application, terminology, product classification, technical requirements, test methods, inspection rules, marking and safety requirements of circuit-breaker capacitors.
This standard applies to circuit-breaker capacitors connected in parallel to the break of AC high-voltage circuit breakers to improve voltage distribution and reduce the recovery voltage rise rate. Hereinafter referred to as "capacitors". This standard does not apply to high-voltage ceramic capacitors. 2 Reference standards
GB311.183 Insulation coordination of high-voltage power transmission and transformation equipment GB 311.2~311.6-83 High voltage test technology 3 Terms
3.1 Circuit-breaker capacitors Circuit-breaker capacitors are connected in parallel with the break of the AC high-voltage circuit breaker to improve the voltage distribution and reduce the recovery voltage rise rate. 3.2 (Capacitor) element (capacitor) element is a component composed of a dielectric and its electrodes. 3.3 (Capacitor) unit (capacitur) unit is an assembly composed of one or more components assembled in a single housing and having lead terminals. 3.4 Rated voltage (U) Rated vol (U.) The voltage (root mean square value) specified in the capacitor design. 3. 5 Rated capacitance (Ch) Rated capacitance (C.) The capacitance value specified in the capacitor design.
3.6 Rated frequency (f.) Rated frcqucncy (f.) The frequency specified in the capacitor design.
3.7 Insulation level
In this standard, insulation level refers to the voltage value that the insulation between the two terminals of the capacitor can withstand. 3.8 Capacitor losses The active power consumed by the capacitor.
3.9 Tangent of the loss angle (tang) The ratio of capacitor losses to reactive power. 3.10 Air temperature at ambient air temperature The air temperature of the place where the capacitor is to be installed. Approved by the State Bureau of Technical Supervision on March 31, 1996 and implemented on December 1, 1996
4 Product classification
4.1 Rated voltage
GB/T 4787--1996
The rated voltage of the capacitor shall be selected from the following values: 10kV.90kV120kV,180kV.240k,360kV4.2 Rated capacitance
The rated capacitance of the capacitor shall be selected from the following values: 1 000 pF,1 500 pF.1 800 pF,2 000 pF,2 500 pF,3 000 pF+4 000 pF,5 000 pF,5 Technical requirements
5.1 Use requirements
5.1.1 Altitude
The altitude of the installation and operation site is divided into: 1000m+2000m, 3000m. 5.1.2 Ambient air temperature
The ambient air temperature of the installation and operation site is -40℃～+40℃. 5.1.3 Installation
The capacitor should be installed horizontally, inclined or vertically. 5. 1.4 Creepage distance
The creepage distance of the capacitor should meet the requirements of the circuit breaker design. 5.2 Performance and structural requirements
5.2.1 Anti-corrosion performance
The exposed surface of the metal parts of the capacitor should have only a good anti-corrosion layer. 5.2.2 Sealing performance
The capacitor should not have any leakage of insulating medium. 5.2.3 Mechanical strength
The capacitor should be able to withstand the vibration during the operation of the circuit breaker and the specified ground test assessment or bending and torsion test assessment. The bending strength and torsion strength parameters are determined by the user and the manufacturer through consultation. 5.2.4 Appearance and installation dimensions
The appearance and installation dimensions of the capacitor should meet the user's requirements. 5.2.5 Capacitance difference
The difference between the measured capacitance and its rated value at 20°C under the rated voltage of the capacitor should not exceed ±5% of the rated value. 5-2.6 Insulation level
The capacitor should be able to withstand the withstand voltage listed in Table 1. This withstand voltage value is applicable to capacitors at an altitude not exceeding 1 000 m. For those with an altitude exceeding 1 000 m, the correction coefficient in GB311.1 shall be used. 5.2.7 Loss tangent (tang)
At rated voltage and rated power, the loss tangent of the capacitor at 20°C should not be greater than 0.002. 5.2.8 Discharge performance
The capacitor should be able to withstand short-circuit discharge at the rated voltage peak. 5.2.9 Partial discharge performance
Under the specified test conditions, the partial discharge of the capacitor should be greater than 10pC. 6 Test methods 6.1 Test conditions GB/T 4787-1996 Table 1 Insulation level Insulation level Rated short-time working withstand voltage RMS 2 h upper frequency withstand voltage RMS Rated lightning impulse withstand voltage peak value The shear test and measurement of capacitors, unless otherwise specified, shall be carried out under the following conditions: Rated switching impulse withstand voltage peak value The ambient air temperature is +5℃～+35℃. The temperature of the capacitor dielectric shall not be significantly different from the ambient air temperature. If calibration is required, +20℃ shall be used as the reference temperature.
When the container is placed in the specified ambient air temperature for an appropriate period of time without power, the temperature of the capacitor medium is considered to be the same as the ambient air temperature.
bThe waveform of the AC voltage used for the test and measurement should be a real standard sinusoidal waveform (see GB 311.3). 6.2 Sealing test
The sealing test of the capacitor is divided into two types: factory test and type test. 6.2.1 The factory test is carried out in accordance with the following method or other effective methods. The capacitor is heated to +50℃~+55℃ in all parts. It is kept at this temperature for at least 2h. There should be no leakage. 6.2.2 The type test is carried out in accordance with the following method: the capacitor is frozen to -40℃ and kept for at least 12 1, and then placed in an ambient temperature not lower than 20℃ for 12h; then the capacitor is heated to +50℃~+55℃ in all parts. It is immediately placed in a water towel with a temperature not higher than 20℃ for at least 55. This heating cycle process needs to be repeated 3 times. There should be no leakage after the test. 6.3 Capacitance measurement
Capacitance measurement should be carried out in a way that can eliminate errors caused by harmonics and accessories in the measurement circuit. The measurement accuracy should be sufficient to reflect the case of a component breakdown.
The initial capacitance measurement should be carried out before the withstand voltage test (6.5) and the discharge test (6.6) at a voltage not higher than 0.15 U. The re-measurement of capacitance should be carried out after the withstand voltage test and the discharge test at a voltage of (0.9~～1.1)t. The actual measured capacitance is based on the last measured value.
Note: When the number of series components in the unit under test is large, the amount of capacitance change caused by the breakdown of one component may be roughly the same as the reproducibility of the measurement or the capacitance change caused by the mechanical force on the component during the withstand voltage test or the difference in capacitor temperature before and after the withstand voltage test. This should be taken into account when judging the test results.
6.4 Measurement of loss tangent (tan)
The loss tangent of the capacitor shall be measured after the withstand voltage test at a voltage of (0.9~1.1)U. and a frequency of (0.8~1.2)f. by a method that can eliminate the error caused by the harmonics and accessories in the measuring circuit. The measurement accuracy shall not be less than 20%. 6.5 Withstand voltage test
The withstand voltage test of the capacitor shall be carried out in accordance with the relevant provisions of B311.2~311.6. During the test, the voltage is applied between the two terminals of the capacitor.
6.5.1 Short-time withstand voltage test
GB/T4787-1996
The time for applying positive voltage to the capacitor: 10s for factory test and 1min for type test. During the test, no flashover or breakdown should occur. 6.5.22h power frequency withstand voltage test
The voltage is applied to the capacitor for 2h. During the test, no flashover or breakdown should occur. 6.5.3 Switching impulse withstand voltage test
The waveform of the switching impulse test voltage is 250/2500s. During the test, the capacitor is subjected to positive and negative impulses for 15 times each. If no flashover or breakdown occurs more than 2 times in the 15 consecutive impulses, the capacitor is considered to have passed the test. 6.5.4 Lightning impulse withstand voltage test
The waveform of the required lightning impulse test voltage is (1.2~5)/50μs. During the test, the capacitor is subjected to positive and negative impulses for 15 times each. If no flashover or breakdown occurs more than 2 times in the 15 consecutive impulses, the capacitor is considered to have passed the test. 6.6 Discharge test
The capacitor is charged to a voltage of 2. with direct current and immediately discharged through a gap as close to the capacitor as possible. This test should be performed 5 times during factory testing; this test should be performed 2000 times during type testing, and there should be no damage after the test. 6.7 Partial discharge test
According to the short-time power frequency withstand voltage test method, apply a power frequency voltage of 1.8U to the capacitor for at least 1s, then quickly reduce the voltage to 1.1U, and keep it at this voltage for 10min. During this 10min, the partial discharge of the capacitor should not increase, and the requirements of 5.2.9 should be met.
6.8 Mechanical strength test
When conducting a mechanical strength test on a capacitor, the capacitor can be installed on the circuit breaker and the mechanical life test and ground test of the circuit breaker can be carried out together. The capacitor can also be subjected to bending and torsion tests alone. There should be no abnormal phenomenon after the test. 1
Inspection rules
7.1 Test classificationWww.bzxZ.net
The capacitor test is divided into: factory test, type test and acceptance test. See Table 2 for test items. Table 2 Test items
Test category
Factory test
Type test
Appearance inspection
Sealing test
Capacitance measurement
Test items
Short-time withstand voltage test
Electric loss angle tangent measurement
Discharge test
Sealing test
Short-time rated withstand voltage test Wet test
2h rated withstand voltage test Dry test
Switching impulse withstand voltage test Avoidance test
Lightning impulse withstand voltage test
Discharge test
Partial discharge test
Mechanical strength test
Technical requirements Article number
5. 2. 1;5. 2. 4
Test method Article number
Test type
Absorption test
7.2 Factory test
Appearance inspection
GB/T4787--1996
Continued table 2
Test items
Short-time power frequency withstand voltage test
Loss tangent measurement
Technical requirements Article number
5. 2. 1; 5. 2. 4
Test method Article number
The purpose of factory test is to inspect the manufacturing defects of capacitors. This test is carried out by the manufacturer for each capacitor. 7.3 Type test
The purpose of type test is to examine whether the design, materials and manufacturing of the capacitor meet the performance and operation requirements specified in this standard. Type test is carried out when new products are manufactured. When there are changes in materials, processes or product structures during production, and these changes may affect the performance of the capacitor, type tests should also be carried out. At this time, only test items related to these changes are allowed. The capacitor used for type testing should be a capacitor that has passed the "export" test. Each type test does not necessarily have to be carried out on the same capacitor, but each test should be carried out on no less than two capacitors. In normal production, type tests should be carried out at least once every five years. Type tests are carried out by the manufacturer. Certificates of these test results should be provided when the purchaser requires them. 7.4 Acceptance test
Acceptance tests are mainly tests carried out by the purchaser according to needs. The purpose of this test is to check whether the capacitor has been damaged during transportation to ensure that the installed capacitor is in good condition. The short-term power frequency withstand voltage test should not exceed 75% of the specified test voltage. If the test is carried out at the same time as the circuit breaker, the test requirements of the circuit breaker should be met. 8 Marking and packaging
8.1 Marking
Each capacitor should be equipped with a nameplate with the following information: a.
Name:
Model:
Number;
Rated frequency, Hz1
Rated voltage, kV;
Measured capacitance, rF or pF;
Year of manufacture:
Note: If the year and month of manufacture are already indicated in the capacitor number, this item may not be marked separately. h.
Temperature range:
Altitude;
Basic weight, kg:
Name or trademark of the manufacturer.
Note, h,;j feedback can be stated in the manual. 8.2 Packaging
The packaging of capacitors should ensure that the container is not damaged under the condition of normal transportation. 9 Safety requirements
9.1 Connection of metal parts
GB/T 4787-1996
The metal parts of the capacitor must be reliably connected to the breakers of the circuit breaker. After the capacitor is out of operation, people must use ground rods to discharge when they need to approach the capacitor
2 Environmental protection
When the impregnation agent of the capacitor is not allowed to dissipate in the environment, measures must be taken. Additional remarks:
This standard is proposed by the Ministry of Machinery Industry of the People's Republic of China. This standard is approved by the Jinguo Power Capacitor Standardization Technical Committee. This standard is initiated by Xi'an Power Capacitor and Xi'an Power Capacitor Research Institute. The main drafters of this standard are Huang Xuan and Xiuzhu Zhang Xiucai.4
Test method number
The purpose of the factory test is to check the manufacturing defects of the capacitor. This test is carried out by the manufacturer on each capacitor. 7.3 Type test
The purpose of the type test is to examine whether the design, material and manufacturing of the capacitor meet the performance and operation requirements specified in this standard.
Type test is carried out when new products are manufactured. When there are changes in materials, processes or product structures during production, and these changes may affect the performance of the capacitor, type tests should also be carried out. At this time, only test items related to these changes are allowed. The core container used for type test should be a capacitor that has passed the "export" test. Each type test does not necessarily have to be carried out on the same capacitor, but each test should be carried out on no less than two capacitors. In normal production, type tests should be carried out at least once every five years. Type tests are carried out by the manufacturer. Certificates of these test results should be provided when the purchaser requires them. 7.4 Acceptance test
Acceptance test is mainly carried out by the purchaser according to needs. The purpose of this test is to check whether the capacitor has been damaged during transportation to ensure that the installed capacitor is in good condition. The short-term power frequency withstand voltage test should not exceed 75% of the specified test voltage. If the test is carried out at the same time as the circuit breaker, the test requirements of the circuit breaker should be met. 8 Marking and packaging
8.1 Marking
Each capacitor should be equipped with a nameplate with the following information: a.
Name:
Model:
Number;
Rated frequency, Hz1
Rated voltage, kV;
Measured capacitance, rF or pF;
Year of manufacture:
Note: If the year and month of manufacture are already indicated in the capacitor number, this item may not be marked separately. h.
Temperature range:
Altitude;
Basic weight, kg:
Name or trademark of the manufacturer.
Note, h,;j feedback can be stated in the manual. 8.2 Packaging
The packaging of capacitors should ensure that the container is not damaged under the condition of normal transportation. 9 Safety requirements
9.1 Connection of metal parts
GB/T 4787-1996
The metal parts of the capacitor must be reliably connected to the breakers of the circuit breaker. After the capacitor is out of operation, people must use ground rods to discharge when they need to approach the capacitor
2 Environmental protection
When the impregnation agent of the capacitor is not allowed to dissipate in the environment, measures must be taken. Additional remarks:
This standard is proposed by the Ministry of Machinery Industry of the People's Republic of China. This standard is approved by the Jinguo Power Capacitor Standardization Technical Committee. This standard is initiated by Xi'an Power Capacitor and Xi'an Power Capacitor Research Institute. The main drafters of this standard are Huang Xuan and Xiuzhu Zhang Xiucai.4
Test method number
The purpose of the factory test is to check the manufacturing defects of the capacitor. This test is carried out by the manufacturer on each capacitor. 7.3 Type test
The purpose of the type test is to examine whether the design, material and manufacturing of the capacitor meet the performance and operation requirements specified in this standard.
Type test is carried out when new products are manufactured. When there are changes in materials, processes or product structures during production, and these changes may affect the performance of the capacitor, type tests should also be carried out. At this time, only test items related to these changes are allowed. The core container used for type test should be a capacitor that has passed the "export" test. Each type test does not necessarily have to be carried out on the same capacitor, but each test should be carried out on no less than two capacitors. In normal production, type tests should be carried out at least once every five years. Type tests are carried out by the manufacturer. Certificates of these test results should be provided when the purchaser requires them. 7.4 Acceptance test
Acceptance test is mainly carried out by the purchaser according to needs. The purpose of this test is to check whether the capacitor has been damaged during transportation to ensure that the installed capacitor is in good condition. The short-term power frequency withstand voltage test should not exceed 75% of the specified test voltage. If the test is carried out at the same time as the circuit breaker, the test requirements of the circuit breaker should be met. 8 Marking and packaging
8.1 Marking
Each capacitor should be equipped with a nameplate with the following information: a.
Name:
Model:
Number;
Rated frequency, Hz1
Rated voltage, kV;
Measured capacitance, rF or pF;
Year of manufacture:
Note: If the year and month of manufacture are already indicated in the capacitor number, this item may not be marked separately. h.
Temperature range:
Altitude;
Basic weight, kg:
Name or trademark of the manufacturer.
Note, h,;j feedback can be stated in the manual. 8.2 Packaging
The packaging of capacitors should ensure that the container is not damaged under the condition of normal transportation. 9 Safety requirements
9.1 Connection of metal parts
GB/T 4787-1996
The metal parts of the capacitor must be reliably connected to the breakers of the circuit breaker. After the capacitor is out of operation, people must use ground rods to discharge when they need to approach the capacitor
2 Environmental protection
When the impregnation agent of the capacitor is not allowed to dissipate in the environment, measures must be taken. Additional remarks:
This standard is proposed by the Ministry of Machinery Industry of the People's Republic of China. This standard is approved by the Jinguo Power Capacitor Standardization Technical Committee. This standard is initiated by Xi'an Power Capacitor and Xi'an Power Capacitor Research Institute. The main drafters of this standard are Huang Xuan and Xiuzhu Zhang Xiucai.
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