Week-11 Challenge: Braking

1) Energy required for braking for different drive cycles can be calculated in excel sheet:

2)

An electric motor can’t develop braking torque at a high speed similar to starting, because the Braking Torque of an EV Motor is not as high as the Acceleration Torque. Therefore Regenerative braking is cannot happen so effectively that we can get all the power back to the battery.

Regenerative Braking:- It is defined as when the vehicle decelerates, the kinetic energy of the vehicle gets converted into electrical energy and gets stored in the battery with the help of the motor. The efficiency of regenerative varies across vehicles but it's roughly near 60%-70%. It is efficient at low vehicle speeds.

Example:- Tesla Roadster

The electrical and mechanical brakes are coordinated in the following ways:

Electric Driven Intelligent Brake System:- Regenerative Brake is only efficient at low speed. It cannot provide enough braking power at high speed. In this case, Electic driven intelligent Brake system is used. In this system, at low speed, the regenerative breaks are applied for maximum efficiency but at high speed, both the regenerative and friction brakes are applied.

Example: Nissan Fuga

-Series: The electrical and mechanical brakes are applied one after another.

3)