ZF-D200 series Digital Close Loop AC Servo Motor Drive Systems Motion Control

A closed-loop servo system is an automatic control system based on feedback control principles, widely used in motion control fields that require high precision and stability. Its core is to monitor the system output in real-time through a feedback mechanism, compare it with the target value, adjust the control signal according to the deviation, and achieve precise control of the system.

The closed-loop servo system mainly consists of the following parts:

• Controller: receives target instructions and feedback signals, generates control signals.
• Driver: Convert control signals into current or voltage to drive the motor.
• Servo motor: converts electrical energy into mechanical energy to drive load movement.
• Sensor: Real time detection of physical quantities such as load position, speed, or torque.
• Feedback loop: Transmit sensor signals to the controller to form a closed loop.

• Command input: The controller receives target position or velocity commands.
• Signal processing: The driver drives the servo motor to rotate according to the control signal.
• Load movement: The motor drives the load to move, while the sensor monitors the load status in real time.
• Feedback comparison: The sensor signal is fed back to the controller, compared with the target value, and the deviation is calculated.
• Error correction: The controller adjusts the control signal based on the deviation and drives the motor to compensate for the error until the deviation approaches zero.

According to the source of feedback signals, closed-loop servo systems can be divided into:

• Fully closed-loop servo system:
  The sensor is directly installed on the load end (such as the workbench) to monitor the actual position of the load in real time.
  Advantages: High precision, can eliminate transmission chain errors.
  Disadvantages: The system is complex and difficult to debug.
• Semi closed loop servo system:
  The sensor is installed at the end of the motor shaft to detect the rotation angle of the motor.
  Advantages: Simple structure and low cost.
  Disadvantage: Cannot completely eliminate transmission chain errors.