Transformers

2

Insulation Problems of HV Power Transformers

Andrey K. Lokhanin

CONTENTS

2.1  Introduction

2.1.1  Chemical Structure of Oil

2.1.2  Movement of Liquid

2.1.3  Mechanical Impurity

2.1.4  Moisture

2.1.5  Temperature

2.2  Choice of Insulation between Windings of the Transformer

2.3  Longitudinal Insulation

2.4  Conclusions

References

2.1    Introduction

Insulation of power transformers represents a complex system consisting of various design components. The insulation may be divided into two parts: internal insulation and external insulation.

The external insulation is the insulation along the cover of bushings, air gaps between bushings of the winding, and of the earthed parts.

Internal (oil-filled, gas, cast) transformer insulation is divided ...