The EV revolution is here! Electric vehicles are selling like hotcakes in the country. Earlier we had written an article on different types of electric vehicles. This article is about different types of electric motors and electric drivetrains.
Types of Electric Motors
Electric motors are the engines of an electric vehicle. The electric motor converts electrical energy into mechanical energy through rotation, this helps the EV to move forward and backwards. There are multiple types of electric motors:
- DC Series Motor
- Brushless DC Motor
- Permanent Magnet Synchronous Motor (PMSM)
- Three Phase Induction Motor
DC Series Motor
The DC Series motor is capable of producing high starting torque. This quality of the motor makes it suitable for traction applications.
The DC series motor was widely in use during the early 1900s. This motor is easy to control and can withstand a sudden boost in load.
The DC series motor is the ideal traction motor. However, maintaining the motor can be difficult due to the brushes and collecters inside the motor.
Brushless DC Motor (BLDC)
The Brushless DC motor is an advanced version of the DC series motor. This motor uses permanent magnets instead of brushes and collectors. The BLDCs are easy to maintain, provide Great efficiency and high starting torque. The BLDCs are widely used in the automotive industries as Belt driven motors or hub motors.
Permanent Magnet Synchronous Motor (PMSM)
The permanent magnet synchronous motor is similar to the BLDC motor which has permanent magnets on the rotor. The PMSM motor also provides great traction characteristics like high power density and high efficiency. The difference between PMSM and BLDC is that The PMSM uses a posterior sinusoidal CEM while the BLDC comes with a trapezoidal CEM. Permanent magnet synchronous motors are used for higher power ratings. Most automakers use the PMSM for their hybrid vehicles and EVs.
Three Phase Induction Motor
Induction motors do not produce a high starting torque.
This is a cheap option in EV motors. However, induction motors can withstand rugged conditions and provide great efficiency. Tesla Model-S uses Induction Motors. Also, Mahindra E20 comes with a three-phase induction motor. These characteristics make the Induction motor a suitable choice for performance-oriented vehicles.
Different drivetrains in EVs
Electric cars are available in different drivetrain options. The placement of the motor plays a vital role in the power delivery and purpose of the vehicle. EVs can come in different configurations, such as a single motor, dual motor, or a separate motor for each wheel.
Vehicles like tesla use a Single or dual-motor setup. Tesla vehicles have one or two centrally-mounted drive units (rear-wheel drive or all-wheel drive). The wheels are directly connected to the motors eliminating transmissions or converters.
The Model S Plaid and the upcoming Tesla roadster come with a three-motor setup. They will have individual motors driving each of the rear wheels and a common motor driving the front wheels.
The Rivian R1T and R1S get separate motors for each wheel,
However, they are in-board and not hub motors. In fact, Porsche is also working on a 4-motor electric drivetrain for the upcoming Macan EV. This setup will increase the agility and handling of the vehicle.