As the core of the drive device, the performance of the motor is crucial, especially the motor speed which directly affects the motor’s output power and efficiency.

Factors determining motor speed:

1. For synchronous motors or asynchronous motors, the motor speed is related to the frequency of the power supply and the number of pole pairs of the motor. The higher the power supply frequency and the fewer the number of pole pairs, the higher the speed. For asynchronous motors, it is also related to the current passing through the motor coil. The larger the current, the closer the speed is to the synchronous speed. There is another type of motor (usually AC and DC motors) whose speed is unrelated to the frequency of the power supply. It is only related to the current passing through the coil.

General motor speed:

2-pole motor 3000 rpm

4-pole motor 1500 rpm

6-pole motor 1000 rpm

8-pole motor 750 rpm

10-pole motor 600 rpm

16-pole motor 500 rpm

2. The most common is the AC asynchronous motor, whose speed is mainly determined by the number of poles and the frequency of power supply. The current power supply frequency is 50Hz (the same across the country). The speed of general motors at 50Hz: The synchronous speed of the two-pole motor is 3000 rpm, and the actual speed is about 2800 rpm (maximum speed), the synchronous speed of the four-pole motor is 1500 rpm, and the actual speed is about 1440 rpm, the synchronous speed of the six-pole motor is 1000 rpm, and the actual speed is about 960 rpm. The four-pole motor is the most common, that is, the general motor.

3. The speed of the motor is determined by the structure of the motor and the way it is powered. Generally, the speed of the motor is from hundreds to thousands of revolutions per minute.

The performance of the motor is affected by many factors, including speed, power, efficiency, torque, etc. Here are some relevant considerations:

Power density: Higher speeds usually increase the power density of the motor, that is, the power that can be output per unit volume or unit weight. This may be beneficial for some applications that require high power output, such as high-speed machinery or vehicle power systems.

Dynamic response: Higher speeds may help improve the dynamic response capability of the motor, allowing it to respond to load changes more quickly or achieve precise motion control. This is important for some applications that require fast response and high-precision control.

Efficiency: The efficiency of the motor usually reaches its maximum value within a specific speed range. Within this speed range, the motor is able to convert the input electrical energy into mechanical energy output with high efficiency. However, if the speed exceeds this range, the efficiency of the motor may decrease. Therefore, it is important to choose the right speed to improve the efficiency of the motor.

Torque output: The torque output of the motor is usually related to the speed. In some applications, such as starting or climbing, higher torque output may be required at the expense of some speed. Therefore, for these applications, a motor with low speed and high torque may be more suitable.

Axial load and vibration: Higher speeds may increase the axial load and vibration experienced by the motor, which may have a negative impact on the motor’s life and reliability. Therefore, the relationship between speed and load needs to be balanced based on the specific application requirements and the motor’s design parameters.

In summary, the effect of speed on motor performance is complex and there is no simple consistent rule. The optimal speed depends on the specific application requirements, including factors such as required power, torque, efficiency and response speed. Therefore, when selecting a motor, it is necessary to comprehensively consider the speed and its relationship with other performance indicators to meet the requirements of a specific application. When it comes to motor performance, the factors affecting speed are complex and diverse.

In addition to the factors mentioned above, here are some other factors to consider:

Power requirements: Specific applications may have specific requirements for power. In some cases, higher speeds can provide greater power output to meet application requirements. However, this does not apply to all cases. Sometimes, lower speeds are required to provide the required power and torque.

Dynamic balance: Motors that rotate at high speeds may require more complex balancing measures to reduce vibration and noise. This may include higher precision bearings, dynamic balancing of rotating parts, etc. Therefore, when running at high speeds, special attention needs to be paid to the balance performance of the motor.

Axial and radial loads: Higher speeds may increase the axial and radial loads borne by the motor. Therefore, when designing and selecting the motor, it is necessary to ensure that the motor can withstand these loads to prevent motor damage or premature wear.

Heat dissipation and cooling: Higher speeds generate more heat and require a more powerful cooling system to ensure that the motor operates within an acceptable temperature range. Therefore, high-speed motors generally require more efficient heat dissipation and cooling measures.

Noise and vibration: Motors rotating at high speeds may generate higher noise and vibration. This may be unacceptable for some applications, so noise and vibration control measures such as soundproofing covers and shock-absorbing brackets are required.

In summary, the impact of speed on motor performance is a complex issue involving the balance of multiple factors. When selecting a motor, it is necessary to comprehensively consider factors such as application requirements, power requirements, torque requirements, balance performance, load requirements, heat dissipation requirements, noise and vibration control, etc. to find the speed range that best suits a specific application.