Started in the year 2002, with the motto of bringing Global Standards to manufacture transformers in the range of 11 to 132 kV.
All in coming materials are inspected to confirm to the Company-National standards.
At every stage of manufacture, transformer is inspected to confirm to company quality assurance program.
Ratio and phase angle error test before connections are brazed. Vector group test before connections are brazed. Magnetic balance.
Before dispatch all transformers are tested at specified pressure to ensure leak proof joints.
(As per IS 2026:1997)
Ratio : Winding resistance / OLTC M.B.B
Contacts
checking
Polarity : Open circuit test
Phase angle error :
Short circuit & impudence test
B.D.V of oil : Separate source voltage test
I.R
values : Induced over voltage test
Polarization Index : Vector group test
Dielectric
discharge : Zero sequence Impedance test
All the design
are tested for heat run test. In house heat run test facility available up to
20,000 kVA. Oil test facilities like tan delta, Resistivity, Acidity, PPM and
suspended particles are available in house.
Transformer
is designed for low losses. Selection of core material with low specific losses
and proper selection of conductor dimensions meet the goals.
Tap turns are
distributed along the length instead of lumping at the center of winding to minimize
short circuit forces.
Cooling ducts are dimensioned to limit hot spot temperature
of windings. At the same time winding spacers/blocks are dimensioned to limit
the stresses on windings due to short circuit forces.
HV and LV Windings are dried by heating and pressed by hydraulic jacks to predetermined short circuit forces.
Core and coil assembly is dried by heating under vacuum in vacuum-drying oven controlled by PLC circuit. After the assembly is dry, it is taken out of oven, windings are then clamped tight. The assembly is housed into its tank and dry transformer oil is filled into it under vacuum drying oven.
Oil is filtered through ultra high Vacuum Filter Machine for limiting the moisture content to less than 5PPM.
Tank,
cable boxes and core clamps are manufactured from weldable quality steel confirming
to Indian standards.
Tanks are designed to withstand the hydraulic pressure
test prescribed in CBIP specifications. Clamps are designed to with stand forces
transmitted on to them by short circuit of windings.
Cable boxes are designed
to facilitate easy connection of cables.