The basic conditions for series resonance test and the test environment shall be carried out in accordance with the relevant provisions of GB/T 16927.1.
1. Appearance inspection: The appearance should have no obvious deformation or damage. The anti-corrosion layer and paint layer should be in good condition, and the nameplates and signs should meet the standard requirements. The main dimensions and electrical clearance meet the requirements of the drawings. The grounding terminal should be no less than M6 and have good contact.
2. Excitation transformer test: Voltage ratio measurement is carried out using a variable ratio bridge or voltage ratio method, and the ratio of the measured voltage ratio to the nominal value should not exceed 1.05.
3. Winding insulation resistance measurement: Using a 2500V megohmmeter, the insulation resistance should not be less than 2500M Ω. Temperature rise test, run at full load for twice the working time according to the working system. The temperature rise of oil immersed windings shall not exceed 65K, and that of dry-type windings shall not exceed 60K. The measurement of winding temperature shall be carried out using the resistance method.
4. Insulation test: The tail end of the frequency withstand winding should withstand a 3kV power frequency voltage for 1 minute without breakdown or flashover. If the tail end is directly grounded, this test is not required.
5. Inductive withstand voltage: The first end of the winding should withstand an AC voltage of 2.0UZN between the shell and the winding group without breakdown or flashover.
6. Reactor test: Check the status of the inductive reactor. The air gap adjustment of the reactor should be sensitive, reliable, and the air gap position indication should be correct. The inductance value of the reactor is measured using the voltage current method, and the measured inductance value should meet the requirements of 5.2.6. The temperature rise test of the reactor shall not exceed 65K for the oil immersed winding and 60K for the dry-type winding, and the temperature rise of the winding shall be measured by the resistance method for the time specified by the continuous working system at the rated capacity of the reactor.
7. The partial discharge test of the reactor should be conducted under the system of the device itself, and should not exceed 10 pC at rated voltage. Devices without this requirement do not need to undergo this test. Special requests shall be negotiated with the manufacturer and agreed upon in the contract. Reactor discharge test: The reactor discharges through an air gap between the high voltage terminal and the ground at rated voltage. Perform two tests within 5 minutes, and there should be no significant changes in local discharge capacity, inductance value, and loss value. The measurement of no-load loss of the reactor is carried out by raising the reactor to the rated voltage with a voltage divider, and measuring the active power input by the excitation transformer. This power is the no-load loss of the reactor. The change before and after withstand voltage should not exceed 10%.
8. Insulation test: The reactor should withstand a voltage of 1.2UN for 1 minute at the upper frequency limit without breakdown or flashover. The lead bushing of the reactor should withstand a voltage of 2.0UZN for 1 minute without breakdown or flashover to the flange.
9. Voltage regulator test: Voltage regulator status check. The regulator should operate flexibly, trip back to zero reliably, and lock back to zero reliably. The minimum and maximum output voltage measurement should not exceed 2V when the regulator returns to zero. When the regulator is adjusted to the upper limit, the ratio of the voltage value to the rated voltage value should not exceed 1.1. Voltage regulator temperature rise test, the voltage regulator should work continuously for twice the working time under full load, and the winding temperature rise should not exceed 60K. The winding temperature rise can be directly measured by thermocouple or measured by resistance method.
Wuhan UHV specializes in producing series resonance (also known as power frequency withstand voltage test equipment) and has been engaged in the electrical measurement industry for many years. Its products have first-class quality and welcome customers to come and purchase.