Frankfurt (Germany), 6-9 June 2011

Dry-type Transformer for Pole Mounted Application

SINGH – US – Session 1 – 0952

Frankfurt (Germany), 6-9 June 2011

ABB dry-type transformers

   Market and technology leader, providing Vacuum cast coil     three complementing technologies from 60 kVA to 63 MVA up to 72.5 kV and with on-load tap changer RESIBLOC ® More than 35 years experience Proprietary technology and R&D departments Open wound

Frankfurt (Germany), 6-9 June 2011

Our value proposition – Dry Transformers Safety – reliability – low losses

 Safety for people and property - no fire hazard or explosion risk  Hundred thousand-fold proven  Intrinsically environmental-safe    New high-tech product line for ultra-efficient dry-type transformers: “EcoDry” New 72.5 kV voltage class dry-type transformer for ultimate safety New IP00 pole mount dry-type transformer PoleDry for avoiding soil contamination and copper theft -

Frankfurt (Germany), 6-9 June 2011

Dry pole mount transformer The motivation for the development

 Risks for oil leakage, theft and related soil contamination  Not attractive for copper theft  Safety for people and environment   Suitable for water and environment protection areas Compact transformer, with comparable dimension and weight as oil-filled Pole mounts

Frankfurt (Germany), 6-9 June 2011

Dry-type IP00 pole mount 100kVA / 15 kV

     VCC coils, realized with cycloaliphatic epoxy for outdoor applications Solid insulation between HV and LV Integrated bushings and off-load taps Stacked core with corrosion protection Used advanced simulation tools to realize dielectric design Integrated bushings mould design Advanced dielectric simulations

Frankfurt (Germany), 6-9 June 2011

Testing- Routine Dielectric

Results

Dimensions (LxWxH): mm Lightning impulse/ AC 95kV AC Withstand 38kV Sound power level PD-level (@ 130% nominal voltage) Temperature rise 1200 x 613 x 1198 Passed Passed 53 dB(A) <10 pC (after pre-stressing to 200%) +45 °C (25°C ambient)

Frankfurt (Germany), 6-9 June 2011

Core corrosion resistance

   All structural steel part are made of stainless steel or Aluminum with no welding joint.

(a) 1000 hrs. of corrosion test for magnetic steel (stacked core samples) Standards used DY991 and DY2101 (b) Stacked core samples after 1000hrs. of salt fog testing (a) reference, uncoated sample (b) successful, coated sample.

Frankfurt (Germany), 6-9 June 2011

Testing- Accelerated Aging- Salt fog Chamber

Test Voltage [U/Uo, kVrms] [Uo=8.7 kVrms] 1.03

1.5

1.8

Total Ageing Time [Hours] 160 378 303 12 hrs. cycle of salt fog chamber cycle 4 Hours Clean UV 4 Hours Salt fog Cooling 2 Hours 2 Hours

Frankfurt (Germany), 6-9 June 2011

Testing- Outdoor- KIPTS

  The installation is placed around 30 m from the Atlantic Ocean in Western Cape of South Africa Almost one year of energized PoleDry transformer confirmed robustness of materials and design Energized Dry Pole mount transformer in South Africa

Frankfurt (Germany), 6-9 June 2011

Conclusions

 Dry-type transformer for pole mount application without enclosure    Increases safety and avoids oil or copper theft Complies with IEC 60076-11 Solid insulation between HV and LV, cycloaliphatic outdoor epoxy    Corrosion resistant coating for core Dielectric simulations confirm the internal and external design Lab and outdoor testing show superior performance under extreme environments 3D-drawing showing single pole installation (from HV side) of PoleDry with HV Delta connection.