2.3.6 Use of Transformers

• Transformer

  An electrical device that changes the voltage of an alternating current (AC) supply
• Transformer components

  • Primary Coil
  • Secondary Coil
  • Iron Core
• Primary Coil


  The coil connected to the input voltage source
• Secondary Coil


  The coil connected to the output load
• Iron Core


  A magnetic core that links the primary and secondary coils and enhances efficiency
• How a Transformer Works

  1. Electromagnetic induction

  2. Alternating current generates magnetic field

  3. Induces voltage in secondary coil
• Transformers only work with alternating current (AC)
• Voltage Transformation


  The voltage change depends on the number of turns in each coil
• Transformer equation

  Vp/Vs = Np/Ns
• Types of Transformers

  • Step-Up Transformer
  • Step-Down Transformer
• Step-Up Transformer

  • Increases voltage
  • Used in power stations
  • Reduces current to minimize energy loss
• Step-Down Transformer

  • Decreases voltage
  • Used near homes
  • Makes voltage safe for domestic use
• Energy loss during transmission is proportional to the square of the current
• Ideal Transformer

  No energy is lost; power in primary equals power in secondary
• Real Transformers

  Some energy is lost as heat, but designed to be highly efficient
• Practical Applications of Transformers

  • Power Distribution
  • Electronics
  • Industrial Use
• Transformers are essential for distributing electricity efficiently
• Small transformers are used in devices like chargers and adapters
• Transformers adjust the voltage of electricity for different machinery
• Understanding the use of transformers is fundamental to grasping how electrical energy is transmitted and used safely and efficiently