HET 250kVA/3kV,2kV,07kV Exciter Transformer

Mode: HET 250kVA/3kV,2kV,07kV
Rated frequency: 30Hz
Working frequency: 30~300Hz
Rated capacitance: 250kVA
HV winding is independent winding:
LV winding voltage: 2x350V (tap voltage 400Vx2)
HV winding voltage/current: 2kV / 83A; 3kV/125A
LV winding current: 2x375A
Cooling methods: ONAN
Heat-resistance: A grade, 25# transformer oil
Winding ≤65K, oil surface ≤55K;
Sound level: 65dB
Impedance level: ≤6%
Structure requirement: oil immersed shell type；silicon steel plate is DQ130-30 high quality cooling rolling silicon steel plate, Bm value very low; Transformer has double coils, cooper lead wire, Low voltage winding and HV winding, adopt electrostatic shielding between two windings which has the function of isolation filter; equips measuring coil, used to measure HV side voltage; there are oil expansion tank and moister absorber on transformer; Oil temperature thermograph and oil level indicator are set on oil expansion tank; Transformer’s spare part and component, e.g. bushing, valve and oil conservator’s structure and layout will not affect the transportation. There are also enough safety distance between transformer HV and LV winding, will not cause partial discharge and corona when testing. Exciter transformer insulation characteristic: Exciter transformer insulation levelwill determin transformer’s safety work and insulation ageing speed. To guarantee no flashover- which coming from external, electric potential raise and cause damage to the main insulation and minor insulation. We will also set insulation layer between HV windings and turn-to-turn. Winding is cylinder type. Capacitance is determin by the winding’s area. When design, we’d try our best to make sure the top and bottom has same area, and compensate with electrostatic shield to improve the initial voltage distribution. Winding skeleton is made of compound insulation tube: can get down partial discharge and shielding the iron coil.

Principle Diagram: