Advantages and disadvantages of brushless DC motors.
Brushless DC motors are a typical integrated product, characterized by the elimination of mechanical elements such as brushes and rectifiers that are commonly seen as shortcomings of DC motors. They have many advantages such as simple structure, stable operation, and convenient maintenance. From a structural perspective, permanent magnet synchronous motors utilize power electronics technology to input AC signals to the motor, resulting in significant optimization of torque fluctuations and low-speed performance. Its structure is relatively simple, consisting of a permanent magnet and two sets (four) of coils. The two sets of coils open and close alternately, with the permanent magnet acting as the rotor and the coil as the stator. When the magnet and coil are in the same line, the set of coils is disconnected and the next set of coils is started. Compared to traditional brushed DC motors, it has better advantages in performance, safety, and reliability.
Precision
brushless DC motors have many advantages and a long lifespan. As they replace carbon brushes and commutators with controllers, their lifespan can reach several times or even more than ten times. The lifespan of carbon brushes is limited, for example, they will wear out after a thousand hours, and at that time, it may be necessary to replace the brushes or even the motor. In addition, the running sound is very low, which is a key concern for us and can be applied to quiet places such as banks, airports, hospitals, etc. Furthermore, the non sparking characteristic can be highly effective in specific flammable and explosive environments. Moreover, due to the use of magnetic field induction, there is no substantial contact, resulting in faster speeds and the ability to operate at low speeds with high power. This eliminates the need for a gearbox to directly drive the load, and the torque characteristics are also quite excellent. The low and medium speed torque performance is excellent, with a large starting torque, low starting current, good reliability, excellent stability, strong adaptability, easy maintenance and upkeep, and high efficiency. The motor itself has no excitation loss or carbon brush loss, reducing multi-stage deceleration loss, and the combined power rate can reach. In addition, it has soft start and soft stop functions, good braking characteristics, and can eliminate the need for original mechanical or electromagnetic braking devices. It is resistant to bumps, has weak vibration and low noise, runs smoothly, and has a long service life.
However, DC brushless deceleration motors also have certain defects. If the operating environment is in a high magnetic field area or in close contact with a high magnetic field, the motor will fail. The reason is that the magnetic field of the rotor components of the motor itself is magnetized, and encountering a high magnetic field will change the rotor magnetic field or eliminate some of the magnetism, causing the motor to be unable to continue working normally. For low-speed starting, there is slight vibration. If the speed increases and the commutation frequency increases, it will be difficult to detect the vibration phenomenon. Moreover, when the vibration frequency of the brushless motor is the same or close to that of the plastic frame, resonance phenomenon is prone to occur, but it can be minimized by adjusting it.
