• Rakesh Transformer Industries Private Limited

Power Distribution Transformers

Rakesh Transformer Industries Pvt Ltd manufactures oil cooled Power Distribution Transformers up to 1600 kVA capacity and voltages up to 33 kV, according to the Indian Standards Institution. The company manufactures transformers according to the individual requirements of customers. A full range of designs is available. All transformers are of the core type with vertical limbs of multi-step section. The core is built up of CRGO low-loss non-ageing type silicon steel laminations. The cores are held together with stout webbing or stiffening plates and insulated bolts. Joints between core and yokes are carefully interleaved the individual packets of laminations are further insulated by division into sections, separated by sheets of insulating paper. The yokes are held between clamps made of steel channels, upper and lower clamps being connected with tie-rods. The clamps and the tie-rods also keep the windings in position and are rigid enough to take short circuit stresses. Generally, the low tension windings are placed next to core with an insulation barrier in between. These windings are of helical type, single or multi-layer or continuous disc-type using flat copper strips depending upon the size and current rating of the transformer. The insulation between LV and HV windings consists of vertical elephantide wedges with elephantide or press pan barriers so as to give most effective cooling. The HT windings consists of cross over coils meant for units up to 1600 kVA where round copper wires are used. In round wire coils manila or Kraft paper is used as inter-layer insulation. The paper used between the layers is so inserted that it gives winding an adequate electrical and mechanical strength, which sustains short-circuit conditions. The windings are rigidly supported by elephantide washers and spacers. Sufficient oil ducts are provided by us between the coils and also between the windings and properly dimensioned for efficient cooling and low electrical stresses. Proper clearances to earth are maintained through washers and spacers. The same are in accordance with and equal distributions of stresses resulting under short-circuit conditions.