Week 3 Session 7
1. Different motors used in EV
a. DC motor
b. BLDC motor
c. PMSM
d. Induction motor
| Sno | DC motor | BLDC motor | PMSM | Induction Motor |
| 1 | A DC motor is defined as electrical motors that convert direct current electrical energy into mechanical energy. | Brushless Direct Current Motor have permanent magnets | Permanent Magnet Synchronous Motor | An induction motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. |
| 2 | Mechanical commutation | A BLDC motor is an electronically commutated DC motor | A PMSM motor is an AC synchronous motor that uses permanent magnets to provide the necessary field excitation. | Works based on EMF |
| 3 | Have commutators | does not have carbon brushes and commutator assembly. | The PMSM is induction motor + brushless DC motor. | No commutators |
| 4 | input is DC | input is DC | input is AC | input is AC |
| 5 | DC motors are used in Elevators, Air compressor, Electric Vehicles | BLDC motors are used in hard drives, CD/DVD drives, washing machines, fans, pumps, robotics, etc. | PMSM motors are used in servo drives, traction control, robotics, aerospace, power factor improvement, machine tools, etc. | Tesla Model S, Mahindra Reva e2o, Indian railways has started replacing its DC motors with AC induction motors |
a. DC motor
Advantages
-High starting torque
-easy speed control
-can withstand a sudden increase in load
-ideal for traction motor
Disadvantages
-high maintenance due to brushes and commutators
-Weight
-More mechanical parts
b. BLDC motor
Advantages
-commutation is done electronically
-No commutators and Brushes
-Easy maintenance
-Low maintenance cost
-high efficiency around 95-98%
-high starting torque
-suitable for high power density design approach
-most preferred motors for the electric vehicle
Disadvantages
-High cost due to permanent magnets
-Overloading reduces Magnets life thermal conditions
c. PMSM
Advantages
-Similar to BLDC motor
-best choice for high performance applications like cars, buses.
-High efficiency
- higher power ratings
Disadvantages
-Very High cost
d. Induction motors
Advantages
-the maximum torque is made available at the starting of the motor
-Squirrel cage induction motors have a long life
-less maintenance
-has more control options
Disadvantages
-requires complex inverter circuit
-Difficult to control