Brushless DC motor

Brushless DC motor

At present, there are various types of motors, which can be divided into brushless motor and brushed motor. Although it is only a word difference, they belong to different motors, so they are different in many aspects. Some users do not know which is brushless motor and which is brushed motor because they do not have a deep understanding of motors. Here's a comparison:

First, whether there is a commonly used brush - commutator

1. The commutation of the brush motor is realized through the contact between the graphite brush and the annular commutator installed on the rotor.

2. The brushless motor feeds the rotor position back to the control circuit through the Hall sensor, so that it can know the exact time of the motor phase reversal. Most motors feature three halls.

Second, Differences in performance requirements

1. Brush motor: It is a traditional product with stable performance.

2, brushless motor: is an upgrade product, its life performance is better than brush motor. But its control circuit is more complex, the aging screening requirements of components is more strict.

Third , life

1, brush motor: can work continuously for about 5000 hours, conventional service life of 2-3 years.

2, brushless motor: can work continuously for about 20000 hours, the conventional service life of 7 to 10 years.

Fourth . Energy Saving

It only consumes 1/3 of the power of a brushed motor.

Between brushless motor and brushless motor, they both have a certain correlation, and they are different motors. Although they all use direct current, only when the two are clear can they help users choose motors and prevent other problems caused by improper use.

Advantages of brushless motor

If you want to use equipment efficiently, then you need to know some of its advantages. Brushless motor has a lot of advantages in the process of use. Below we will specifically list their advantages.

1, speed is not limited by mechanical reversing, if the use of air bearings or magnetic bearings, can be up to hundreds of thousands of revolutions per minute. The system has higher density and higher efficiency.

2, with fast response, large starting torque, from zero speed to rated speed with rated torque performance.

3, mature technology, stable performance, can save customer enterprise research and development, product costs, high matching, suitable for a variety of fields.

4. The permanent magnet of brushless motor is now mostly made of rare earth NdFeb with high magnetic energy product.

5, the motor control system is simple.

6. Wide speed range, the motor can run in the range of low, medium and high speed. It can operate at full power at any speed.

7, overload capacity is strong, to meet the needs of the vehicle plugging. Good braking effect, in the car downhill or braking motor can be completely into the generator state, to charge the battery, at the same time play the role of electric braking, reduce the burden of mechanical braking. Motor small size, light weight, large specific power, can reduce the weight of equipment, save space.

8. Brushless motor has the advantages of good low voltage characteristics, strong torque overload characteristics, large starting torque, small starting current and so on.

9, good external characteristics, can output large torque at low speed, so that it can provide large starting torque;

10, high efficiency, strong overload capacity;

11, regenerative braking effect is good, because its rotor is permanent magnet material, the motor can enter the generator state when braking;

12, small size, high power density;

13, no mechanical commutator, the fully enclosed structure, can prevent dust into the motor, high reliability;

Brushless motor has many advantages, which can show a lot of advantages in the process of application, which requires us to fully grasp their advantages and better use.

Application requirements for brushless motors

According to the requirements of the use of the motor, whether in performance, life, or other aspects, basically is better, understand the use of brushless motor requirements, later use, in accordance with the requirements to use the line, what is the use of the motor requirements?

1. When using brushless motor, the middle axis of the reduction motor needs to be in the middle, because if it is not in the middle, the error of the middle shaft of the reduction motor will lead to the service life of the reduction motor.

2, to be stable on the horizontal plane, to ensure the stability of the base of the deceleration motor, and the oil of the deceleration motor discharge tank needs to be cleaned. When running, in general, it will not produce too much vibration and noise. If there is, it is damaged gear. At this time, it is necessary to add some lubricant to the gear, and then install protective devices.

3. When moving parts on the output shaft of the reduction motor, it can not be knocked with a hammer. Knocking Ronggui leads to the press of the reduction motor transmission parts, which may cause damage to the internal parts. Use requires the use of rigid fixed coupling.

4. When using brushless motor, the staff should not be close to the oil mark in general, except for some operations such as ventilation plug or oil discharge plug for the deceleration motor. Before use, the accuracy of the reduction motor should also be carefully checked. Ensure that the operation can work in a stable, no impact, small vibration, no leakage oil environment.

Users in strict accordance with the requirements of the use of brushless motor, efficiency will be significantly improved, running speed will be slightly faster. So in order to better use of the motor, we should still use it according to the requirements.

Protection measures of brushless DC motor

The proper use of brushless DC motor can prolong its life. The motor can play a key role in many equipment, and sometimes it will involve the whole equipment. The motor needs to do a good job of relevant protection, through protection, can reduce the damage to its.

1, if the load of DC brushless motor is too large, or because of the improper use of the motor will cause large current and the power transistor will be burned. In order to protect the driver because the current exceeds the specification, it is generally to increase the power transistor current resistance or current as the protection of the motor.

2. When the load of the DC brushless motor is not small, the energy and overvoltage sent back to the driver by the motor end when it stops rotating will endanger the driver, which can be prevented with the overvoltage protection circuit and the regenerative energy dissipation circuit. The control department can judge and timely warn.

In order to reduce the damage to DC brushless motor, but also to reduce the wear and tear of parts, before use, we must take appropriate protective measures in advance to protect the normal operation of the motor. Prevent damage caused by improper protection.