Transformers are critical devices in power systems used to change AC voltages. Their basic working principle is based on Faraday's law of electromagnetic induction, where voltage transformation occurs through magnetic flux exchange between the primary and secondary coils. Below is a detailed introduction to the main structure and components of transformers.
1. Core
- Function: The core, made from high permeability materials such as silicon steel sheets, is designed to concentrate and enhance the magnetic field, improving conversion efficiency.
- Types: Includes various shapes like E-type, I-type, C-type, etc., selected according to design requirements.
2. Windings
- Primary Winding: Connected to the power source side, responsible for generating the magnetic field.
- Secondary Winding: The output voltage side, which acquires energy from the primary winding via electromagnetic induction.
- Material: Copper or aluminum is commonly used due to their excellent electrical conductivity.
3. Insulation Materials
- Role: To prevent short circuits between windings and between windings and the core, insulation materials like kraft paper, epoxy resin, mica, etc., are used.
- Importance: Ensures safe operation and extends the lifespan of the equipment.
4. Oil Tank
- Specific to Oil-Immersed Transformers: For oil-immersed transformers, the tank is filled with insulating oil that provides both electrical insulation and cooling.
- Maintenance: Regular checks on oil level and quality are necessary to ensure normal operation.
5. Cooling System
- Natural Cooling: Suitable for small transformers, utilizing natural air convection for heat dissipation.
- Forced Oil Circulation Cooling: Large transformers use forced oil circulation cooling systems, circulating oil forcibly to dissipate heat.
6. Tap Changer
- Usage: Used to adjust the transformer’s output voltage, especially under conditions of significant grid voltage fluctuations.
- Location: Can be installed on either the high-voltage side or low-voltage side depending on specific design requirements.
