REGENERATIVE BRAKING (Syllabus: GS Paper 3 – Sci and Tech)

Context: State-led incentives and subsidies are driving significant changes in the electric vehicle sector. One key innovation is regenerative braking, which enhances energy use efficiency in these vehicles.

Braking

• About: It is the mechanism through which a moving automotive vehicle decelerates.
• It primarily reduces the vehicle's kinetic energy, translating its motion into other forms.
• Energy Conversion: Vehicles in motion possess kinetic energy proportionate to their speed.

o Braking involves converting this kinetic energy into other forms due to the law of energy conservation.

• Types of Brakes

o Mechanical Brakes (Disc Brake)

o Utilizes brake pads pressing against a rotating disc.

o Friction generated converts kinetic energy into heat.

o Features like disc perforations aid in heat dissipation.

• Induction Brake

o Involves inducing electric currents in a conducting wheel.

o These currents create a magnetic field opposing an external magnet's field.

o Resulting drag slows down the wheel, dissipating energy as heat through metal resistance.

Regenerative Braking

• About: It is a brake system designed to convert the kinetic energy of the wheels into a form that can be stored and used for other purposes.
• Mechanism: During braking, the traction motor in electric vehicles functions as a generator, converting kinetic energy back into electrical energy.
• Comparison: Contrasted with rheostatic braking, regenerative braking stores recovered energy rather than dissipating it as heat.

How Does a Motor Become a Generator?

• Motor Basics: A motor comprises a stationary stator and a rotating rotor, generating motion through interaction with a magnetic field.
• Operation: When a motor operates in reverse, as a generator, mechanical energy turns the rotor to induce electrical current in the stator.
• Application: Switching the motor's function allows electric vehicles to implement regenerative braking, converting kinetic energy into stored electricity.