Hollow cup motor is a special DC permanent magnet servo, control motor, can also be classified as micro motor. The use of hollow cup motors has several significant advantages and certain disadvantages. Here's a breakdown of the pros and cons:
I. Advantages
① High efficiency:
The rotor of the hollow cup motor adopts a hollow structure, which reduces the iron loss and copper loss of the rotor, thus improving the efficiency of the motor. Its energy conversion efficiency is very high, the maximum efficiency is generally more than 70%, and some products can even reach more than 90%, which is much higher than ordinary iron core motors.
② High reliability:
Because the rotor of the hollow cup motor is hollow structure, there is no open circuit or short circuit, so its reliability is high. In addition, the life of the hollow cup motor is also relatively long, which can ensure long-term stable operation.
③ Low maintenance cost:
The hollow cup motor has a simple structure and no wearing parts, so its maintenance cost is low. In practical applications, it is only necessary to carry out regular checks on the appearance of the motor to ensure that there is no obvious damage.
④ Good speed control performance:
The hollow cup motor has good speed regulation performance, and the speed of the motor can be adjusted by changing the input voltage or frequency, which is very useful for occasions where the speed needs to be accurately controlled.
⑤ Low noise:
Because the rotor of the hollow cup motor is hollow, there is no mechanical friction and vibration present in traditional motors, so it is low noise, suitable for applications that require a quiet environment.
⑥ Small size, light weight:
Because there is no iron core, the hollow cup motor is relatively small in size and light in weight, which makes it an advantage in some applications that require small and lightweight, such as drones, power tools, and so on.
⑦ Fast response speed:
The mechanical time constant of the hollow cup motor is small, the response speed is extremely fast, and some products can reach less than 10 milliseconds, which is very advantageous for the servo system that needs a fast response.
⑧ Less electromagnetic interference:
With high quality brush and commutator structure, commutation spark is small, additional anti-interference device can be eliminated and electromagnetic interference can be reduced.
Ii. Disadvantages
① Large starting current:
The starting current of the hollow cup motor is large, so it will cause a certain impact on the power grid when starting. In order to reduce the starting current, soft start or frequency conversion start can be used.
② High cost:
Compared with traditional motors, the manufacturing cost of hollow cup motors is higher, mainly due to the relatively complex manufacturing process. Therefore, its price is also relatively high, and may not be suitable for some applications with higher cost requirements.
③ Limited output power:
Because the rotor of the hollow cup motor is composed of conductive coils, and there is no iron core support, its output power is limited. This makes hollow cup motors unsuitable in some applications that require high power output, such as large mechanical equipment, generators, etc.
④ High requirements for the working environment:
Hollow cup motor has higher requirements for the working environment, if there is a lot of dust, iron filings and other debris in the working environment, it will affect the normal operation of the motor. Therefore, when using the hollow cup motor, it is necessary to ensure that the working environment is clean, dry and well ventilated.
⑤ Heat dissipation problem:
Due to the small volume and large power density of the hollow cup motor, long time operation may produce large heat. Although its heat dissipation performance is relatively good (such as copper coil both inside and outside the surface of the air flow), but in some high temperature environment applications still need to pay attention to heat dissipation problems.
⑥ Magnetic field control is difficult:
Because the stator of the hollow cup motor is composed of permanent magnets or electromagnetic coils, its magnetic field control is relatively difficult. This makes hollow cup motors unsuitable for applications that require precise control of magnetic fields, such as some high-precision control systems.