HET 25kVA/20kV,10kV Exciter Transformer

Mode: HET 25kVA/20kV,10kV
Rated frequency:50Hz 
Single phase
Cooling methods: ONAN
Rated voltage:
Input voltage:10 kV
Output voltage: 13.7kV/60kV (tap voltage ,test with water termination)
Input current: 50A  HV current: 36.6A/4A(tap current)
Impedance voltage: < 6%
Shielding methods: Set electrostatic shield layer between HV windings.
Exciter transformer protection: equip piezoresistor for each HV output, exciter transformer’s input and output terminal connects with the ground via zinc oxide arrester, this methods can protect the operator and the equipment itself when test object breakdown. Structure: steel housing, HV bushing equips on the oil tank, equips wheels, movable, oil tank is shell-type, lead out the Low voltage with porcelain bushing. E ach terminal is lead out by relative voltage grade bushing. HV bushing lead wire go through isovolumetric capacitance core, exterminal insulation is fiber glass bushing. Bushing has corona rings. Oil tank has oil conservator to make sure the capacitance core in the oil. HV bushing can guarantee 20kV corona free. 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: