Servomotors may be classified as direct current servomotors and alternating current servomotors. It is also called the motor for control because servomotor is an electric motor primarily designed and built for use in feedback control systems. These motors have a high dynamic response, requiring little inertia of the rotor. They have smaller diameter and longer length and are designed to work allied to a servo-converter that follows a true reference to torque, speed or position.
The specialties of a servomotor are http://cgevaporator.com/ smooth rotation, high dynamic, low noise and vibration, the motor output torque proportional to the voltage applied and the direction of the torque determined by the instantaneous polarity of the control voltage. The most widely used type of servomotor is the one that uses alternating power supply. In them the rotor uses permanent magnets, the housing is made of aluminum and the stator is formed by a packet of blades and a sensor (resolver – analog or resolver – digital) is responsible for providing feedback signals to the servo inverter. Thus the converter is able to precisely actuate the servomotor. An alternating signal according to Faraday’s induction law allows the speed and position of the rotor shaft to be obtained.