In traditional power stations, the original energy source spins a turbine which connects to an electric generator. The generator converts mechanical energy into electrical energy. This working is based on which fundamental principle of physics?

Faraday principle of electromagnetism

Explanation:

In 1831, Michael Faraday found that a conductor placed in a rotating magnetic field induces a voltage in the conductor and if the circuit is closed, current would flow. This voltage produced is through electromagnetic induction.

The turbine is connected to the rotor which carries the electromagnet coils, as the turbines spins, the rotor also spins producing a rotating magnetic field, the rotating magnetic field cuts the stator and induces voltage on the output of the generator.