Servo motor in the operation process, there will be a variety of small problems, of which servo motor jitter is one of the most common problems.
First, the jitter caused by mechanical structure can be divided into two cases:
1, no load jitter:
a. The foundation of the motor is not strong, the stiffness is not enough or the fixing is not tight.
b. The fan blades are damaged, which damages the mechanical balance of the rotor.
c. The shaft is bent or cracked. You can solve the problem by fastening screws, replacing fan blades, and replacing machine shafts.
2, if the load after jitter, is generally caused by the fault of the transmission device, can determine the following parts of the defect:
a. The rotation of the belt wheel or coupling is unbalanced.
b. The center line of the coupling is inconsistent, so that the motor does not coincide with the mechanical axis of the transmission.
c. The transmission belt connector is unbalanced. It can be solved by correcting the transmission device to balance it.
2. Jitter caused by the speed ring problem:
Velocity loop integral gain, velocity loop proportional gain, acceleration feedback gain and other parameters are improper. The greater the gain, the greater the speed, the greater the inertial force, the smaller the deviation, and the easier it is to jitter. Setting a small gain can maintain the speed response and is less prone to jitter.
3. Jitter caused by fault of compensation board and servo amplifier of servo system:
The sudden power failure and great jitter are caused by BRK terminal of servo amplifier and improper setting of parameters. The acceleration and deceleration time constant can be increased, and the motor can be slowly started or stopped by PLC without jitter.
4. Jitter caused by load inertia:
The load inertia increases due to the problems of guide rail and lead screw. The moment of inertia of guide rail and lead screw has a great influence on the rigidity of servo motor drive system. Under fixed gain, the greater the moment of inertia, the greater the rigidity, the easier to cause motor jitter; The smaller the moment of inertia, the smaller the rigidity, the more difficult the motor is to shake. By replacing the smaller diameter guide rail and screw to reduce the moment of inertia and thus reduce the load inertia to achieve the motor does not jitter.
5. Jitter caused by electrical parts:
a. The brake did not open, the feedback voltage instability and other factors caused. Check whether the brake is open, add the encoder vector control zero servo function, and output a certain torque by reducing the torque to solve the jitter. If the feedback voltage is not normal, check whether the vibration period is related to the speed, if it is, check whether there is a fault in the connection between the spindle and the spindle motor, whether the spindle and the pulse generator installed at the tail of the AC spindle motor are damaged, if not, check whether the printed circuit board is faulty, and it is necessary to check the circuit board or readjust.
b. The sudden jitter in the operation of the motor is mostly caused by the lack of phase, and it should be focused on checking whether the fuse melt is fused, whether the switch contact is good, and whether the power grid phases are electricity.
Post time: Dec-21-2023
