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Electric wheelchair motor selection problem

In other electric vehicles, brushless motors have already been used, so why not use them in electric wheelchairs, it is not difficult to understand the advantages and disadvantages of the two motors.
What are the characteristics of brushless motors?
advantage:
a) Electronic commutation replaces traditional mechanical commutation, with reliable performance, no wear and tear, low failure rate, and a lifespan about 6 times longer than that of brushed motors, representing the development direction of electric vehicles;
b) It is a static motor with small no-load current;
c) high efficiency;
d) Small size.
shortcoming:
a) There is slight vibration when starting at low speed. If the speed increases, the commutation frequency increases, and the vibration phenomenon will not be felt;
b) The price is high and the controller requirements are high;
c) Resonance is easy to form, because anything has a natural vibration frequency. If the vibration frequency of the brushless motor is the same or close to the vibration frequency of the frame or plastic parts, it is easy to form resonance, but the resonance can be adjusted by adjusting phenomenon is reduced to a minimum. Therefore, it is a normal phenomenon that an electric vehicle driven by a brushless motor sometimes emits a buzzing sound.
d) It is more laborious to ride by foot, and it is best to combine electric drive and pedal assist.

What are the pros and cons of brushed motors?
advantage:
a) The speed change is smooth, almost no vibration is felt;
b) Low temperature rise and good reliability;
c) The price is low, so it is chosen by many manufacturers.
shortcoming:
a) The carbon brushes are easy to wear and tear, which is troublesome to replace and has a short lifespan;
b) When the running current is large, the magnet steel of the motor is easy to demagnetize, which reduces the service life of the motor and the battery.

 


Post time: Oct-25-2022