Week 3 Session 7

Answer:

BLDC MOTOR	PMSM MOTOR	INDUCTION MOTOR
BLDC motor is a DC motor.	PMSM motor is an AC motor.	Induction motor is an AC motor.
Starting current is rated.	Starting current is rated due to the permanent magnets.	Starting current is very high.
The torque produced is low.	The torque produced is high	It enables low torque at low speeds.
BLDC motor uses a controller.	Control algorithms are used.	No controller is required for fixed speed.
Efficiency is around 85% to 90%	Efficiency is around 92% to 97%	Efficiency is lower compared to BLDC motor.

Advantages of BLDC motor:

• High efficiency.
• Higher speed ranges.
• Operated effectively.
• Reduced Size.
• High dynamic response.
• Better speed versus torque characteristics.
• Noiseless operations.
• Less power maintenance.
• More efficient.
• Longer life span.

Disadvantages of BLDC motor:

• A brushless DC motor costs comparatively more than a brushed DC motor.
• When the Brushless DC motor is operated at low speeds, slight vibrations occur.

Advantages of PMSM motor:

• High efficiency.
• Better torque and better performance.
• Less noisy.
• Reduced size.
• More efficient.
• Low heat generation.
• Low torque ripple.

Disadvantages of PMSM motor:

• A drive is required.
• Complex control system.
• Higher costs.

Advantages of Induction motor:

• Simple and rugged in construction.
• Robust nature.
• Cheaper costs.
• Less maintenance cost.
• can be operated in polluted and explosive environments.

Disadvantages of Induction motor:

• During light load conditions, the power factor of the motor drops to a very low value.
• Speed control is difficult.
• High Input surge currents.
• Less starting torque.