Power Transformers, Sohar
VOLTAMP has recognised the huge local and global opportunity and has implemented state of the art facility at Sohar 200 Km from Muscat as new subsidiary company named Voltamp Power LLC. Spread over an area of 80,000 sq. mtrs. this plant has a total built up area of 14,500 sq. mtrs. This ramps up our capacity to 10,500 MVA, making us one of the biggest facilities in the Middle East and North Africa. This state of the art plant has been specially created to facilitate production of heavy duty transformers up to 220 kV.
WINDINGS
Windings are designed to withstand high short circuit withstand capability, uniformity of surge voltage distribution and effective heat dissipation which is important to achieve product reliability.
High Voltage windings mostly use disc type winding which ensures better short circuit with-stand capability, uniform surge distribution and effective heat dissipation.
And helical type windings comprising of machine transposed copper conductor made of several strands in parallel (CTC – continuously transposed conductor) are used for low voltage windings. Spacers are provided between the strands to accommodate oil ducts for insulation and cooling.
Windings are produced on special vertical winding machines to meet the exact dimensions. Adjustable mandrel ensures compliance to designed winding diameter of coil of transformer.
Care is taken to uniformly distribute the tapping winding across the core limb. This ensures proper ampere turn distribution enabling electromagnetic balance at any tap.
Whole winding area is air conditioned which eliminates presence of any dust particles and winding dimensions closer to designed diameter and height.
TESTING
VOLTAMP POWER Transformer at Sohar is implementing state of art testing facility which has been ordered on HEAFELY Switzerland. VOLTAMP POWER Transformers will be subjected to all the necessary routine tests in accordance with IEC ensuring they withstand conditions beyond normal operating conditions. Apart from routine tests, special & type tests which can be carried out in this facility include:
- Temperature rise test
- Lightening & Switching impulse test
- Induced over- voltage test with PD measurements
- Measurement of noise level
- Measurement of harmonics & zero sequence impedance
- Capacitance & tan delta measurement
- SFRA (Sweep frequency Response Analysis)
This test facility will be able to carry out all Routine, Type & Special tests as per IEC 60076 except Short Circuit Test.
QUALITY CONTROL
VOLTAMP POWER Transformers will go under strict Quality assurance Plan which covers all the stages starting from design, selection of vendors, sourcing of raw materials, inspection on receipt of raw materials, measurement and tests after each manufacturing stage and Final acceptance test in presence of customer or their nominated representative.
IN HOUSE HANDLING AND TRANSPORTATION
Entire Power transformer facility is epoxy floored. Air coasters are used to move the windings, sub-assemblies and complete transformers facilitating jerk free movement inside the plant which is very essential for safety and long life of power transformer being very heavy mass.
For transportation to site VOLTAMP suggests use of hydraulic axles for Power transformers weighing beyond 60 Tons and use of Impact recorders to measure shocks during transit.
INSTALLATION & AFTER SALES SUPPORT
VOLTAMP POWER has dedicated team of engineers to provide services during installation & commissioning or on demand. We are committed to attend any calls within 24 hours. VOLTAMP Power is also planning to keep standby standard Power Transformer unit at its facility so that same can be mobilized to site within 24 hours of requirement.
Transformers, Rusayl
CORE CUTTING
The Core is constructed from Lamination of Cold Rolled Grain Oriented, Low Loss Electrical Sheet, featuring excellent
magnetic properties; Slit coils conforming to BS 6404 are sourced from reputed mills.
The core laminations are cut to a designed geometry on a most modern fully automated CNC Core cutting machine of GEORG,
Germany. The individual stampings are coated on both sides with insulating material that is both oil and temperature resistant.
Testing
The following Routine Tests (as per IEC 60076) are carried out on all Transformers:
* Separate Source Voltage withstand test.
* Induced Over voltage Test.
* Voltage Ratio and Vector Group test.
* Measurement of Winding Resistance.
* Measurement of No Load Loss and Magnetizing Current.
* Measurement of Load Loss and Impedance Voltage.
* BDV Tests on Oil.