Bharat Bijlee Limited

Prabhadevi, Mumbai, Maharashtra

The Unit Auxiliary Transformer is the Power Transformer that provides power to the auxiliary equipment of a power generating station during its normal operation. This transformer is connected directly to the generator out-put by a tap-off of the isolated phase bus duct and thus becomes cheapest source of power to the generating station. It is generally a three-winding transformer i.e. one primary and two separate secondary windings. Primary winding of UAT is equal to the main generator voltage rating. The secondary windings can have same or different voltages i.e. generally 11KV and or 6.9KV as per plant layout.

Greenstar from Bharat Bijlee is a new-generation gearless machine for elevators powered by a permanent magnet synchronous motor. Compact modular designs, light weight and low operating noise levels make it especially suitable for machine room-less applications. Real saving in energy consumption (up to 30%), and in space and routine maintenance requirements, contribute to a significant reduction in cost of ownership. The gearless machine, configured with the KEB variable frequency drive and our 30 years of elevator experience, is an unbeatable value proposition.

For Power Transformers, the short circuit withstand capability is of prime importance. We ensure this through the adoption of a unique clamping arrangement of the windings at accurately determined pre-stress levels. For primary voltages of 132 kV and 220 kV, ability of windings to withstand system transients and lightning surges are of vital importance. The insulation design and quality of materials used, ensure that our product withstands these stringent test requirements upto a BIL of 1050 KVP when tested in accordance with national international client specific standards.

BBL motors can be continuously overloaded by 10% or can be used up to ambient temperature of 55°C. Temperature rise will be as per Class F limits.All motors up to 280M frame are designed for 50°C ambient.2Z Bearings are standard up to 180L frame which are filled with high temperature grease suitable up to 140°C.Additional anti tracking protective coating of air drying varnish is applied on the winding overhangs.