# PPT_CHAPTER_6

# Slide_1: Electric Motor:
* An Electric Motor is an electrical machine that converts electrical energy into mechanical energy.
* The basic idea of an electric motor:
Electricity is given at one end and at the other end, an axle(metal bar) rotates giving the power to drive any kind of machines.
* Priciple:
When a current-carrying conductor is placed in a magnetic field it experiences a magnetic field and starts rotating according to the direction given by Fleming’s Left-Hand Rule for a motor.

# Slide_2:Types of Motor
Motors are classified based on the power i.e. AC or DC and their method for generating rotation.

1. DC MOTORS
Brushed DC motor
Brushless DC motor
Stepper (STP)
2. AC MOTORS
Induction motor (IM)
Synchronous Motor (PM)

# Slide_3:Electric Motor Comparison

# Slide_4: AC motors over DC motors

* Why does TESLA exclusively use AC motors?
While most of the commercially available EV’s in the market employ a BLDC motor in their powertrain.
Tesla motors remains as an exception from the lot.
* Reasons for opting AC motors over DC motors
1. Cost
2. Efficiency
3. Regenerative braking

# Slide_5: Important Parts in an Electric Motor
1. Armature
2. Commutator
3. Brushes


# Slide_6: Working of an Electric Motor:

An electric motor uses the magnetic push to rotate the current-carrying conductor.
To find the direction of the force in each side of the loop Flemings Left-Hand rule for motors(also called motor rule) is used.


# Slide_7: Advantages of an Electric Motor

* For the same horse-power rating, the initial cost of an electric motor is less compared to fuel engines.
* An electric motor has comparatively few moving parts and hence longer lifespan.
* Minimum maintenance is required.
* Electric motors don’t require fuel, hence there is no need for engine oil maintenance, also no greenhouse gas emissions.
* Electric motors are highly-efficient with the ratings that range from 80% to 95%.

# Slide_8: BLDC Motor
* BrushLess DC motor or BL motor is the DC motor which does not have brushes.
* The commutation is done electronically.
Principle of BLDC motor:
* The reversal of current is done by hall-effect sensors.
* The hall-effect sensors generate a high or low signal whenever rotor magnetic poles cross the hall sensors, which can be used to detect the position of the shaft.

# Slide_9: TYPES OF BLDC MOTORS:

They are classified based on their design but their working procedure remains the same.

* Outer rotor design
* Inner rotor design

Figure: BLDC Motor Types

# Slide_10: WORKING OF BLDC MOTOR

Figure:Working of BLDC Motor

# Slide_11: Regenerative Braking System

* The technique of recharging the batteries while braking is called Regenerative Braking System.
* Regenerative Braking System is used in fully electric vehicles and hybrid electric vehicles that use an electric motor

* Need of Regenerative Braking System
Using RBS technique, the fuel economy of vehicles can be improved. It further reduces greenhouse gas emissions. The enrgy which would have been lost due to thermal dissipiation is thus harnessed and restored in the system.

# Slide_12: REGENERATIVE BRAKING SYSTEM IN FULLY-ELECTRIC VEHICLE
Regenerative action in EV

# Slide_13: REGENERATIVE BRAKING SYSTEM IN HEV

Regenerative action in HEV

# Slide_14: BENEFITS OF RBS

All-electric vehicles in motion can utilize this advantage of regeneration to re-collect energy that would have been lost.
Some of the advantages are
* Reduction in engine wear out
* Smaller components
* Increase in the performance
* Increase in the overall efficiency of vehicles
* Increases the life span the friction braking system.