OIL DISTRIBUTION TRANSFORMERS OIL DISTRIBUTION TRANSFORMERS Presented By 1 Dr. Eng. Adel Abdel-Twab Farag

2 OUTLINE 1- Introduction 2- Transformer Work Principle 3- Transformer Construction 4- Conclusions

1- Introduction 1- Introduction A transformer is a static device that transfers electrical energy from one circuit at one voltage level to another circuit at another voltage level without changing frequency and without any electrical contact between them. 3

2- Transformer Work Principal 4 The transformer works in the principle of mutual induction.

3- Transformer Construction 3- Transformer Construction A basic transformer consists of: 5 Magnetic core HV coils LV coils Tank Bushings Oil

3-1 Magnetic core 6  The core is made out of transformer sheet steel laminations assembled.  The thickness of the lamination varies from 0.35 mm to 0.5 mm.

3-1 Magnetic core 7

3-1-1 Core arrangement 8 The windings of core –type enclose the core  Core type

3-1-1 Core arrangement 9 The core of shell–type encloses the windings  Shell type

3-2 Bushing 10 In order to insulate and to bring out the terminals of the winding from the tank, apt bushings that are made from porcelain must be used.

3-3 OIL 11 Mineral oil is the dominant insulating fluid, which also has cooling function.

12 4. Conclusion The distribution transformer should be kept at its acceptable loading and periodically maintenance to increase its efficiency and reliability.

13