The core standard for the AC withstand voltage test of high-voltage reactors is GB 50150-2016 “Code for Handover Test of Electrical Equipment in Electrical Installation Projects”, which is a key project to test the main insulation strength of reactors. The following is a detailed interpretation of the standards and key points based on this standard and relevant technical regulations.
I. Scope of the Test
According to Article 9.0.6 of GB 50150-2016, the scope of the AC withstand voltage test for reactors during handover is as follows:
Reactors with a rated voltage of 110kV and below, including arc suppression coils, dry-type or oil-immersed reactors, must undergo the AC withstand voltage test.
For reactors with a rated voltage of 110kV and above, the test is generally replaced by induced voltage or partial discharge measurement in accordance with the standard.
II. Test Voltage Standards
The test voltage is carried out in accordance with Appendix D.0.1 of GB 50150-2016, with specific values as follows:
Rated voltage 3kV: 22kV for oil-immersed, 17kV for dry-type
Rated voltage 6kV: 32kV for oil-immersed, 24kV for dry-type
Rated voltage 10kV: 35kV for oil-immersed, 30kV for dry-type
Rated voltage 15kV: 45kV for oil-immersed, 38kV for dry-type
Rated voltage 20kV: 55kV for oil-immersed, 47kV for dry-type
Rated voltage 35kV: 85kV for oil-immersed, 72kV for dry-type
Rated voltage 66kV: 140kV
Rated voltage 110kV fully insulated structure: 200kV
Special Note
For reactors with graded insulation: For reactors with the insulation level at the neutral point lower than that at the line end, the test voltage is based on the insulation level at the grounded end or the end.
Duration: Unless otherwise specified, the full voltage withstand time is 1 minute.
Frequency requirement: The test should use a 45-65Hz power supply.
III. Conditions to be Met Before the Test
The following items must be completed and qualified before the test to avoid equipment damage:
Insulation resistance: The insulation resistance of the winding together with the bushing, absorption ratio or polarization index test is qualified.
Dielectric loss: For reactors with a rated voltage of 35kV and above, the dielectric loss factor and capacitance of the winding together with the bushing are qualified.
Insulating oil: The insulating oil of oil-immersed reactors, such as breakdown voltage and moisture content, are qualified.
Standing time: After oil filling, oil-immersed reactors need to stand still. For 110kV and below, it is usually 24 hours, and the test can be conducted after the bubbles are eliminated.
IV. Test Method and Judgment
Test method
Connect the high-voltage output end of the test transformer to the reactor winding, and short-circuit and ground the non-tested winding.
Start from a lower voltage and increase the voltage at a rate of 1-2kV/s until the specified test voltage is reached.
Maintain the full voltage for 1 minute, then uniformly reduce the voltage to zero.
Qualified standard
No breakdown, no flashover, and no abnormal sounds during the test.
The insulation resistance does not significantly decrease before and after the test, usually not less than 70% of the pre-test value.
V. Safety Precautions
Discharge operation: After the test, the tested item must be fully discharged to prevent residual charges from causing personal injury.
Environmental conditions: The relative humidity of the air should not exceed 80%, and the temperature of the equipment should not be lower than 5℃.
Site isolation: Set up barriers and warning signs in the test area, and prohibit non-operating personnel from entering.
The AC withstand voltage test of high-voltage reactors is a strict insulation test and should be carried out after all non-destructive tests are qualified. The test voltage strictly follows the requirements of Appendix D.0.1 of GB 50150-2016. If a breakdown occurs during the test, it usually indicates a serious insulation defect, and the equipment needs to be repaired or replaced.
Post time: Apr-07-2026