Advantages of high-voltage test transformers:

(1) High voltage: The primary voltage of the high-voltage test transformer is 220 V or 380 V, but the secondary voltage of a single test transformer often reaches several thousand volts to tens of thousands of volts. Test transformers with secondary voltage exceeding 750 kV usually adopt multiple cascade structures.

(2) Small current: The rated current of the high-voltage test transformer is actually the capacitance current of the tested product, so it is generally less than 1 A. However, the secondary current of test transformers used for projects such as cable and large motor test, external insulation test, line corona test, etc. can reach several amperes.

(3) Short working time: Due to the short withstand voltage time of the tested product, the high-voltage test transformer generally has a short-time working system of 0.5 h or 1 h except for external insulation test, line corona test, and cable test. .

(4) High-voltage test transformers are generally single-phase, indoor installations (also made into outdoor installations): all are oil-immersed self-cooling structure, winding insulation layer is thick, high-voltage windings are usually grounded.

(5) The insulation level of the first and the end of the secondary winding of the high-voltage test transformer is different: the first is high potential, and the end is directly grounded or grounded through an ammeter.

(6) High design and manufacturing process requirements: Due to the high working voltage, the insulation structure has a decisive influence on the overall size of the high-voltage test transformer. The body generally requires vacuum drying, and vacuum oiling is required for more than 100kv.