A06B-2082-B403  fanuc 主轴功率伺服放大器

3. Dc servo motor

3.1 Structure

3.2 Working Principle

The working principle of DC servo motor is basically the same as that of ordinary DC motor. Electromagnetic torque is generated by the action of armature flow and air gap flux to make the servo motor rotate. Armature control is usually used to change the speed by changing the voltage while keeping the excitation voltage constant. The lower the voltage, the lower the rotational speed. When the voltage is zero, stop rotating. Because when the voltage is zero, the current is zero, so the motor does not produce electromagnetic torque, nor does it spin.

Dc servo motor is widely used in numerical control system, but DC servo motor also has some disadvantages: its brush and commutator are easy to wear; Limit of maximum speed of motor and application environment; The structure is complex, the manufacture is difficult and the cost is high.

Two servo driver

Step 1: Concept

Servo driver is also known as servo amplifier or amplifier, is the input from the controller pulse signal or analog signal after internal calculation and amplification output to the motor device.

2. Structure and principle

Servo driver is mainly composed of servo control unit, power drive unit and communication interface unit. The servo control unit includes position controller, speed controller, torque controller and current controller.

Servo driver can be divided into two modules, power board and control board. The power board is the strong electric part, which includes two units, one is the power drive unit IPM used to drive the motor, the other is the switching power supply unit to provide digital and analog power for the whole system. The control board is the weak current part, the control core of the motor and the running carrier of the core control algorithm of the servo driver technology. The control board outputs PWM/PFM signal through the corresponding algorithm, which is used as the driving signal of the driving circuit to change the output power of the inverter, so as to achieve the purpose of controlling the AC servo motor.