The structural types of transformer windings and key points for operation and maintenance

The winding is the circuit part of the transformer that generates the magnetic field and transmits electrical energy. It is made of copper or aluminum wires wrapped in insulating paper and is wound around the iron core column of the transformer. Its insulation strength, mechanical strength and heat resistance directly determine the operational safety and service life of the transformer, and it is one of the core components of the transformer. 

The structural types of transformer windings mainly include layer-type and pancake-type. The windings of the layer-type structure are continuously wound in sequence along the axial direction, which has simple process and convenient manufacturing, and is often used in low-loss power transformers; the windings of the pancake-type structure are continuously wound into pancakes along the radial direction, and then many pancakes are arranged along the axial direction to form a structure. It has good insulation performance and high voltage tolerance, and is often used in 110kV and above high-voltage large and super-large transformers. Most of the power transformers produced in China adopt concentric windings, that is, the high-voltage and low-voltage windings are wound on the same cylindrical wire sleeve outside the iron core column, with insulation gaps and heat dissipation channels left between them. 

The key points for the operation and maintenance of windings mainly include the following aspects: First, conduct regular inspections of the insulation performance of the windings. Through insulation tests, identify problems such as insulation aging and damage, and prevent insulation breakdown. Second, monitor the operating temperature of the windings to avoid accelerated insulation aging due to overheating. The temperature monitoring system can be used to obtain real-time information on the winding temperature and take cooling measures promptly. Third, inspect the connection terminals of the windings to ensure a secure connection and avoid poor contact that may generate electric sparks and damage the windings. Fourth, regularly clean the dust and debris on the surface of the windings to keep them clean, preventing the accumulation of dust from affecting heat dissipation and insulation performance. 

A reasonable winding structure design and standardized operation and maintenance work can effectively extend the service life of the winding, ensure the stable operation of the transformer, and reduce the probability of faults.