Regenerative Braking

What is Regenerative Braking?

A regenerative braking system is an inbuilt part of self-charging hybrid cars or electric vehicles (EVs) that uses the energy from braking.

A vehicle with a traditional internal combustion engine uses a friction-based braking system. Just after the driver presses the brake pedal, brake pads are pushed against the spinning brake discs and make contact. This contact then creates a resistive force that slows down the vehicle. During this contact, a tremendous amount of heat occurs, in other words, the energy of the vehicle is wasted. This is a pretty good working mechanism for old cars, but it is not appropriate for the new era because of its inefficiencies. For the last few years, vehicles with renewable energy have outperformed, and the energy lost must be minimized as much as possible, which leads to new mechanisms to evolve, such as regenerative braking.

Regenerative braking prevents energy loss in a considerable amount that can be fed back into the battery.

Principle

If you drive a Mercedes EQB or any model of Tesla, you will realize the car slows down just after you take your feet off the accelerator without pressing the brake pedal. Actually, this happens in all automobiles, but the effect is more obvious in electric vehicles. This is because the regenerative braking system of the vehicle is activated.

The resistive force the driver experiences is caused by electromagnetic resistance or magnetic drag. An electric motor gives sufficient energy that is transmitted to the wheels to move the car. However, when you lift off the accelerator, the electric motor becomes a generator rather than a power input. As it tries to generate electricity, it resists the rotation of the wheels which leads resistive torque to occur, slowing down the vehicle.

Electromagnetic Induction

After taking off the gas pedal, the rotor inside the electric motor keeps rotating. However, this time, it doesn’t turn by the electrical power but rather by the kinetic energy being produced by the wheels. Inside the motor, there is a magnetic field. As the motor spins, it cuts through a magnetic field, generating electricity through a process called electromagnetic induction.

Resisting Motion

The created electricity pushes back on the motor, known as back-EMF. This is like a motor saying, “Slow down”. This pushback creates a resistive force that is experienced by the driver.

Advantages of Regenerative Braking

Less Wear on Brake Pads & Rotorr

Since conventional braking system is not used as much as in normal cars, brake pads and rotors can last longer.

Increased Driving Range for EVs

The feature of capturing kinetic energy and converting it to electrical energy keeps your battery charged, which helps you to cut off the time you spend charging throughout the year.

Reduced Fuel Consumption in Hybrids

In hybrid cars, there is still a need for internal combustion engines, but you don’t have to rely on them that much by charging the battery with the regenerative braking system.

Disadvantages of Regenerative Braking

Not as efficient at Lower Speeds

Due to reduced kinetic energy, it may not be as effective as at higher speeds, but the battery will be charged anyway.

Can Offer Less Braking Power

After taking your foot off the accelerator, the car will eventually stop. However, when you encounter an emergency event on the road, regenerative braking will not stop you immediately, you must use the conventional braking system.

The Impact of Regenerative Braking

Regenerative braking recovers energy that is lost as heat. It also enhances EV range and reduces brake wear. Regenerative braking is a major step toward energy efficiency, although it is less effective at lower speeds. Along with improved sustainability, it also opens the door for future innovations to eliminate wasted energy and recycle it.

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