How Brushless DC Motors Work and Their Advantages

An electric motor transforms the electrical energy into mechanical energy. A growing star on the market, brushless DC motors are gradually taking the place of brushed DC motors. Brushless motors have more benefits than brushed motors.
They are a crucial component of contemporary drive technology and are most frequently used to actuate motors, machine tools, electric bikes, robotics, computer peripherals, and electrical power generation. These motors are now so efficient in terms of the cost, size, and dependability of the entire system with the development of sensorless technology and digital control.

What is a Brushless DC Motor and How does it Work?

Electric motors convert electrical energy into mechanical energy. E-bike has a brushless DC motor, also known as BLDC motor, which does not need brushes like older electric motors did to change the direction of current flowing to the motor. Brushless motors have been the norm for more than ten years because their brushes reduce the motors' efficiency and have a tendency to wear out over time.

You may notice a lot of cables winding around a ring of poles when you open a BLDC motor. It is the stator that turns into an electromagnet when the motor controller injects current into the cables from the battery. A circle-shaped row of permanent magnets will also be visible inside or outside the stator. Depending on the type of BLDC motor, the magnets' orientation concerning the stator may differ, but the rotor is always present.

What are the Advantages of a Brushless DC Electric Motor?

Longer Lifespan

In contrast to brushed motors, brushless motors lack brushes, as the name implies. Because there are no brushes, there is no friction between moving parts that could eventually wear out, which prolongs the motor lifespan even more.

Greater Efficiency

Brushless motor efficiency can reach up to 85 to 90 percent. A BLDC motor's mechanical power can account for up to 90% of its total electrical input. Compared to brushed DC motors, which have an efficiency output power rating of roughly 75 to 80, which is significantly higher.

Reduce Noise

Brushless DC motors operate with comparatively less noise. In other motors, the brushes are in constant contact, which causes noise and sparking while in touch. Brushless DC motors are preferred to avoid electrical noise.

More Power Output

A brushless DC motor is suitable for high-performance applications because it can generate high power in a small package. Brushless DC motors provide maximum torque due to continuous rotation. A brushless DC motor can provide more power output from the same input energy than a brushed motor.

Low Maintenance

Due to the absence of carbon brushes, brushless DC motors require less frequent brush replacement, which lowers maintenance expenses.

More Reliable

Brushless motors are more reliable and suitable for hazardous areas because they lack a commutator that can wear out or produce sparks.

Brushless vs. Brushed Motors

Rendering of the brushless motor in the Ranger-S e-bike

A brushless motor is a good option if you want a lengthy lifespan. The lifespan of a brushed motor is determined by the type of brush used, which can range from 1,000 to 3,000 hours on average. In contrast, a brushless motor can operate for thousands of hours on average because they do not have brushes to wear out. The bearings' wear is the limiting factor.

When comparing brushed and brushless motors, one might anticipate that brushless motors would have greater overall efficiency. Brushless motors do not experience the same energy losses from friction or heat. They have longer battery life and a better range for e-bikes because brushless motors can provide more power for the same amount of input energy.

A DC voltage supply, including a battery, may efficiently drive brushed DC motors. A controller is required to electronically commutate brushless motors, which adds to the complexity and cost of the system as a whole.

Brushless motors are more reliable because they have fewer moving components and experience less wear and tear than brushed motors. Brushes in brushed motors inevitably wear out, hence in performance loss and motor failure. On the other hand, brushless motors have no brushes, so they require less upkeep and last longer.

Finally, brushless motors operate more quietly and smoothly compared to brushed motors. It is because brushless motors do not vibrate or make noise. After all, they use electronic commutation rather than mechanical brushes.
It is merely a summary of motor efficiency; we also advise you to consider the efficiencies of the entire drive system, including gearboxes and controllers.

Summing

In conclusion, electric bike motors are a fantastic way to enjoy riding without pedaling for long distances. We have discussed the two types of motors: Brushed and Brushless DC motors.
Brushless motors last longer and are more reliable than brushed motors. Higher maximum speeds are also possible with brushless motors but are more expensive. Choose an electric motor for your e-bike wisely! With the correct electric motor, you can propel yourself on a trip to remember.