JB/T 6204-1992 Large high voltage AC motor stator insulation withstand voltage test specification JB/T6204-1992 standard download decompression password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
JB/T 6204-1992
Stator insulation of large high-voltage AC motor
Withstand voltage test specification
Published on 1992-06-16
Ministry of Machinery and Electronics Industry of the People's Republic of China Mechanical Industry Standard of the People's Republic of China
Implemented on 1993-01-01
Mechanical Industry Standard of the People's Republic of China
Stator insulation of large high-voltage AC motor
Withstand voltage test specification
Subject content and scope of application
This standard specifies the voltage limit of the stator coil and winding insulation of large high-voltage motors to the ground withstand voltage test. JB/T6204-1992
This standard is applicable to the AC and DC withstand voltage test of the stator coil and winding insulation of synchronous generators, synchronous condensers and AC motors to the ground.
This standard does not apply to solvent-free integral impregnation type and explosion-proof safety type large AC motors. 2 General requirements for power frequency AC withstand voltage test 2.1 The test voltage frequency should be 50Hz and the waveform should be as close to a sine wave as possible. The voltage applied during the test should start from no more than half of the full value of the test voltage, and then increase to the full value evenly or in sections at a rate not exceeding 5% of the full value. The time for the test voltage to increase from half value to full value should be no less than 109. Under the full value voltage, the test time should last for 1min, then quickly drop to less than 50% of the full value, and then disconnect the power supply. 2.2 During the coil withstand voltage test, the straight part of the coil that is not anti-corona should be wrapped with tin foil or aluminum foil (or put into a simulated iron core). The wrapping length is the iron core length plus 10mm for coils with motor rated voltage of 3kV and below, and the iron core length plus 20mm for coils above 3kV. For the anti-corona coil, the withstand voltage test should be carried out after the anti-corona treatment. During the test, it is allowed to use the low-resistance layer as the grounding electrode, but multi-point grounding is required. 2.3 During the withstand voltage test, the voltage should be applied between the winding and the casing. At this time, the winding, temperature measuring element and iron core that are not involved in the test should be connected to the casing and grounded.
2.4 If the motor needs to be tested for overspeed, accidental overcurrent, short-term overtorque and short-circuit mechanical strength, the factory withstand voltage test should be carried out after these tests; if a temperature rise test is required, the withstand voltage test should be carried out immediately after the temperature rise test. 2.5 Before the power frequency AC withstand voltage test is carried out after the motor is assembled, the insulation resistance of the winding should be measured with a corresponding megohmmeter. The insulation resistance value measured in the cold state should be calculated according to the rated voltage of the motor and should not be less than 1Ma/kV. 3wwW.bzxz.Net
Power frequency AC withstand voltage test voltage (effective value) 3.1 The symbols and units used in the withstand voltage test are as follows: P is the rated power of the motor, generator: MVA; motor: MW; phase regulator: MV. U is the rated voltage of the motor winding: kV.
For the coil-type coil and the undivided stator composed of it, the test voltage is shown in Table 1, Table 1
Finished coil
Test stage
After the offline slot is replaced
After the head is connected and the insulation is connected, the stator is completed
After the motor is assembled
Phase splitting\
Phase splitting\
2.75U+4.5
2.5U/+2.5
2.25U+2.0
Note: 1》For motors whose neutral points of the three output terminal windings are not easy to separate, undivided phase testing is allowed. The Ministry of Machinery and Electronics Industry approved JB/T6204-1992 on June 16, 1992. Test voltage: P≥10. 2U≤6. 2.75U+4.5. 2.25U+2.0. 2.75U+6.5. 2.25U+4.0. 2.0U+3. 0. 1993-01-01 implementation: JB/T 6204-1992. For coil-type coils and the stators they consist of, the test voltage is shown in Table 2. Table 2
Dot size
Manufacturer
Finished coil
After finishing the mold
After connecting the ends and insulation
Before the joint line is taken off the line
After finishing the mold of the joint line
Connect the joint line diagram, after the ends are connected and insulation is completed, after the stator is assembled in the motor
2.75U+4.5
2.25U+2.0
2.75U+1.0
Phase-split 0.80(2.0U+1.0)
Note: For stators assembled and tested at the manufacturer, the withstand voltage test is still carried out according to Table 1. 3.4
For the strip coil and its non-petaled stator, the test voltage is shown in Table 3. Table 3
Finished coil
After the lower coil is off the line
After the upper coil is off the line, the slot is punched and replaced with the lower coil for trial welding and the head is assembled and the connection is installed, the lead wire is wrapped with insulation, and the stator is completed. After the motor assembly
Bar coils and their petal stators, the test voltage is shown in Table 4. Table 4
Manufacturer
Finished line diagram
After the lower line diagram is off the line
Test stage
After the upper coil is off the line, the slot mold is punched and the lower line diagram is tested and welded together, and the connection wire is installed and the lead wire is wrapped with insulation JB/T 62041992
2.25U+2.0
2.75U+1.0
0.80×2.5J
6
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