1. Definition of servo motor
A servo motor is a device that converts electrical energy into mechanical energy, mainly used to control the rotation of mechanical components. As an actuator in the automatic control system, it can convert the input voltage signal into angular displacement or angular velocity on the shaft, thereby driving the control object. The servo motor has the characteristics of high precision, high speed and high efficiency, and can convert the voltage signal into torque and speed to achieve precise control.
2. Working principle of servo motor
In the servo system, the servo motor receives the control signal and drives the motor after processing by the controller. The encoder feeds back the position and speed information of the motor to the controller in real time. The controller adjusts the running state of the motor according to the feedback signal to ensure that the preset position and speed requirements are met. The servo motor has the characteristics of high precision, fast response and high stability, and is widely used in occasions that require precise control.
3. Main features of servo motors
1. High precision: The servo motor adopts a closed-loop control system, and the encoder monitors the position and speed of the motor in real time to ensure that the motor shaft accurately tracks the command signal, usually achieving sub-micron or even higher precision.
2. Fast response: The servo motor has excellent dynamic response characteristics and can respond quickly to command changes in a short time. It is suitable for occasions that require frequent acceleration and deceleration, fast start and stop, or high dynamic load changes.
3. Strong stability: When the load changes suddenly or there is external interference, the servo motor maintains stable operation through feedback adjustment to avoid loss of step or oscillation, and has good anti-interference ability.
4. Strong overload capacity: The servo motor can withstand loads exceeding the rated value in a short time, has good overload capacity, and is suitable for use in occasions that require short-term peak torque.
5. Wide speed range: The servo motor can provide stable torque output in a wide speed range, and can maintain good performance regardless of low or high speed.
6. High efficiency: The drive control technology of the servo motor enables it to maintain high working efficiency under various working conditions, which helps to save energy and reduce consumption.
7. Intelligent integration: The servo motor supports multiple control modes (such as position, speed, and torque control), and can communicate with the host computer through the bus (such as EtherCAT, CAN) to achieve intelligent control.
4. Common types of servo motor failures
1. Bearing failure: Bearings are key components in servo motors. Common failures include jitter, abnormal noise, and shaft jamming. These failures may be caused by improper mechanical load, excessive vibration and impact, overspeed operation, shaft current influence, overheating, moisture or contaminant ingress. To avoid these failures, the rated load must be strictly controlled, long-term overload operation must be avoided, and measures must be taken to prevent shaft current problems, while regular preventive maintenance is performed.
2. Shaft seal failure: Servo motors used in polluted environments usually need to be equipped with oil seals for protection. Shaft seal failures are mainly manifested as wear, which may be caused by accidental damage or normal wear. To prevent such failures, it is recommended to replace the shaft seal every 3 months, and no longer than 12 months.
3. Stator and winding failure: Winding problems are also one of the common failures of servo motors, which may cause short circuits and internal burning. The reasons include overload, overvoltage, phase loss, incorrect wiring, inappropriate drive parameter settings, excessive ambient temperature, cooling device failure, and physical damage. To avoid these faults, it is necessary to strictly control the load of the servo motor, ensure correct wiring and drive parameter settings, and perform regular inspections and maintenance.
4. Rotor and shaft failures: The rotor is usually composed of permanent magnets and may face fracture or deformation failures. These failures may be caused by excessive vibration, too many starts or reversals, overheating or unexpected collisions. To prevent these failures, the motor should be operated under rated load and excessive vibration and collision should be avoided as much as possible.
5. Other faults: Including motor encoder alarm, broken shaft, unbalanced no-load current, abnormal sound during operation, difficulty starting, etc. These faults may be caused by incorrect wiring, electromagnetic interference, mechanical vibration, unbalanced power supply voltage, wrong winding connection, etc. Solutions include checking the wiring, adjusting the power supply voltage, and repairing the rotor.
Posted
Apr 09 2025, 02:09 AM
by
Amaris07