Technology Class

According to the regulations, the number of full voltage air load impact tests, the investment of new products should be impacted 5 times continuously; after large repair, it should be impacted 3 times. Each impact interval is not less than 5min, and someone should be sent to the scene to monitor the transformer before the operation. Check the opposite whether there is any abnormality.

Although the DC withstand voltage test and leakage current measurement methods are the same, their functions are different. The former is to test the insulation's dielectric strength, and its test voltage is higher; the latter is used to check the insulation condition, and the test voltage is relatively low.

When an indoor switch using SF6 gas as insulation and arc extinguishing medium leaks during use, the leaked SF6 gas and its decomposition products will accumulate in the indoor low-level space, resulting in localized hypoxia and toxicity, posing a serious danger to the life safety of the staff entering the room.

When cable faults occur, obstacles must be eliminated quickly to restore communications as soon as possible, first of all, the nature of the obstacle should be judged and then select the appropriate instrument to determine the precise location of the obstacle in time to carry out cable line repair work, the determination of the precise location of the obstacle is generally used to determine the precise location of the obstacle to the instrument cable fault tester.

Both DC internal resistance and AC internal resistance measurements have their own unique principles and operations. DC internal resistance is relatively simple to measure and is based primarily on Ohm's law. AC internal resistance, on the other hand, requires the injection and detection of a sine wave signal from which the corresponding impedance value is obtained.

Hydrogen-cooled generator with water-cooled stator, segmented rotor coils, advanced ventilation, and safety features including sealing and cooling systems.

The vacuum oil filter efficiently removes moisture, gas, impurities, and pigments from oil under high vacuum, enhancing its quality by reducing dielectric loss and acidity, and improving demulsification.

The tan delta test on a transformer, also known as the Dielectric Dissipation or Loss Angle test, is a method used to assess the quality and condition of the transformer's insulation system. This test is crucial for determining the health of the transformer and identifying potential insulation faults or aging issues.

Measurement of capacitance and dielectric loss of circuit-breaker capacitor is a very important task to ensure safe and stable running of circuit-breaker. However, due to serious electric interference to on-site measurement, dielectric losses of more and more 500kV circuit-breaker capacitor exceeded the limit at 10kV test voltage according to the CSG trial standard. To address the above-mentioned problems, the paper proposes that methods of using different frequency power source and boosting test voltage be utilized to measure the capacitance and dielectric loss. Based on the above measuring methods, several common test schemes are put forward and application ranges are also analyzed followed by capacitance and dielectric loss measurement for some 500kV circuit-breaker capacitor at substation. Test results indicate that the dielectric loss of capacitor reduces as the voltage rises; the change in test voltage frequency can effectively shield the interference from on-site electric field.