The power frequency AC high voltage test transformer is referred to as the test transformer for short. It has good electrical insulation performance and is generally widely used for the insulation performance test of electrical equipment and electrical materials. However, it can also be used as a small power high voltage power supply. The test transformer is generally a step-up transformer. This test transformer uses the power frequency high voltage induced by its secondary side to conduct insulation performance tests on various electrical products and insulating materials. After the electrical equipment is delivered, handed over or overhauled, AC withstand voltage test shall be carried out to assess the insulation level of equipment insulation withstanding overvoltage. Therefore, no matter in the high-voltage laboratory or test site of the manufacturing department and the operation department, the AC voltage withstand equipment should be set up. You can check the samples for this.
Test transformer is an indispensable electrical equipment for withstand voltage test in the repair and construction of motors, transformers and electrical appliances. The test transformer is mainly used for power frequency withstand voltage test of electrical products, partial discharge measurement, thermal stability test of insulation medium, etc; For medium and high frequency electrical equipment, special frequency test transformer can also be used for withstand voltage test and measurement of relevant electrical parameters.
The principle of the test transformer is the same as that of the ordinary power transformer, but the difference is that the test transformer has high working voltage, short service time, small temperature rise and generally no radiator. In addition, the load of the test transformer is small and mostly capacitive load. The capacity of the test transformer is relatively smaller than that of the power transformer.
In principle, the AC high-voltage test transformer is no different from the power transformer, but due to the different operating conditions between them, what are the characteristics of the AC high-voltage test transformer and the power transformer in terms of design and use?
(1) The AC high-voltage test transformer is single-phase, while the power transformer is generally three-phase.
(2) The output of AC high-voltage test transformer is high voltage, small current and small capacity; Power transformers generally have large capacity.
(3) The insulation margin of AC high-voltage test transformer is small, and the working mode is intermittent; The power transformer has large insulation margin and its working mode is continuous.
(4) The AC high-voltage test transformer shall be able to withstand multiple discharges.