1, servo system (servo mechanism) is to make the object's position, orientation,

State is accused of output can follow the input target given value (or) any change of the automatic control system. Servo positioning by pulse, basically can understand it, servo motor to receive a pulse, will rotate one pulse of the corresponding point of view, so as to realize the displacement, because, the function of the servo motor itself has a pulse, so each rotation Angle of a servo motor, send out the corresponding number of pulses, in this way, and the servo motor to accept pulse forming the echo, or closed loop, as a result, the system will know how many pulses sent to the servo motor, how much charge pulse back again at the same time, in this way, can be very precise control of the motor rotation, so as to realize accurate positioning, can reach 0.001 mm. Divided into the dc servo motor with brush and brushless motors. Has the motor of low cost, simple structure, big start torque, wide speed range, easy control, need maintenance, but the maintenance is not convenient (in carbon brush), electromagnetic interference, has asked for the environment. So it can be used in ordinary industrial and civil occasions is sensitive to the cost.

Brushless motor is small in size, light weight, the output is big, fast response, high speed, small inertia, the rotation smooth, stable torque. Intelligent control is complex, easy to implement, the flexible electronic commutation, can square wave or sine wave phase commutation. Motor free maintenance, high efficiency, low operating temperature, electromagnetic radiation is very small, long life, can be used for all kinds of environment.

2, ac servo motor and brushless motor, divided into synchronous and asynchronous motor, the current motion control with synchronous motor, in the scope of its power is big, can do a lot of power. Big moment of inertia, high rotational speed is low, and with the increasing power and fast. Thus suitable for the application of low speed running smoothly.

3, the inside of the servo motor rotor is a permanent magnets, drive control of U/V/W three-phase electric form of electromagnetic field, under the action of rotating rotor in this field, at the same time, the motor with encoder feedback signal to drive, drive according to the feedback value compared with the target, adjust the Angle of the rotor rotation. The precision of the servo motor is determined by the precision of the encoder (line number).

Ac servo motor and brushless dc servo motor on the function of the difference: ac servo is better, because it is a sine wave control, torque ripple is small. Dc servo is trapezoidal wave. But dc servo is simpler and cheaper.