Useful practical knowledge！ An inseparable servo motor
Issuing time:2018-02-03 00:00
Servomotor (servo motor) refers to the engine that controls the operation of mechanical elements in servo system, which is a kind of auxiliary motor indirect transmission device. Servo motor can make control speed and position accuracy very accurate. It can transform voltage signal into torque and speed to drive control object. The rotor speed of the servo motor is controlled by the input signal and can react quickly. In the automatic control system, it is used as an actuator and has the characteristics of small time constant, high linearity, starting voltage and so on. It can convert the received signal into the angular displacement or angular velocity output on the shaft of the motor. It is divided into two kinds of DC and AC servo motors. The main feature is that there is no self rotation when the signal voltage is zero, and the speed decreases with the increase of torque.
The servo motor is widely used in various control systems. It can convert the input voltage signal to the mechanical output of the motor shaft, and drag the controlled element to achieve the control purpose.
The servo motor has direct current and communication points; the earliest servo motor is a general DC motor. When the control precision is not high, the general DC motor is used as a servo motor. At present, the current DC servo motor is a small power DC motor from the structure. Its excitation is mostly armature control and magnetic field control, but armature control is usually used.
The classification of the rotating motor, the DC servo motor can meet the requirements of the control system well, but because of the existence of the commutator, there are many shortcomings: the commutator and the brush are easy to produce sparks, interfere with the work of the driver, and can not be used in the situation of combustible gas; the brush and commutator exist friction. A large dead zone will be produced by rubbing.
The structure is complex and it is difficult to maintain.
AC servo motor is essentially a two phase asynchronous motor. There are three main control methods: amplitude control, phase control and amplitude phase control.
In general, the servo motor requires the motor speed to be controlled by the added voltage signal; the speed can be changed continuously with the change of the voltage signal, the motor is fast, the volume is small, and the control power is small. Servo motors are mainly used in various motion control systems, especially servo systems.