How Transformers Work and Their Use in the National Grid

Recap: Transformer's Role in the National Grid

Electricity Generation: Most electricity in the UK is generated at large power stations distributed across the country.
Step-Up Transformers: Increase voltage to around 400,000 volts to minimize energy losses during transmission through the national grid.
Transmission: Electricity sent through a network of wires and pylons.
Step-Down Transformers: Decrease voltage to around 230 volts for safe usage in homes.
Summary: Transformers either increase or decrease electricity voltage.

Iron Core: Central component connecting primary and secondary coils.
Primary Coil: Input side where alternating potential difference is applied.
Secondary Coil: Output side where induced potential difference causes current flow.

Alternating PD Applied: Alternating potential difference applied to primary coil causes current flow, generating an alternating magnetic field.
Magnetic Field in Iron Core: Alternating magnetic field in primary coil induces an alternating magnetic field in the iron core (iron can become magnetized).
Induced PD in Secondary Coil: Iron core's magnetic field induces a potential difference in the secondary coil.
Current Flow in Secondary Coil: If part of a complete circuit, current will flow in secondary coil.

Transformers transfer current using induced magnetic fields due to insulated wires (plastic prevents direct conduction).
Purpose: Allows change in the size of the potential difference.
- Step-Up Transformer: Increases voltage (e.g., 10V input -> 20V output) due to more turns in the secondary coil.
- Step-Down Transformer: Decreases voltage due to fewer turns in the secondary coil.

Hope this made sense!