A servomotor is a special kind of engine that can be controlled by using negative feedback to adjust direction, acceleration and rotational speed.
Principle of operation
The servomotor is an integral part of the entire system of devices. It consists of such components:
- Feedback sensor.
- Control blocks and power supplies.
Motor in that system performs its main function and converts electrical energy into mechanical. The second element is a sensor that is mounted on drive unit shaft and monitors its direction and rotations frequency. It will also give feedback to control systems. Also for such a task it is quite often used an encoder.
Received results in form of signals come into special control devices. Further, in these blocks, the obtained data are analyzed and compared with programmed ones. Then they give a command that directly effects on speed and frequency of shaft`s rotation.
Data transfer and power supply are produced by cables. The three main ones are the most commonly used. Two of them supply voltage to electric motor, and the third one transmits a signal through whole system.
Servomotors are divided into several categories according to different characteristics. Most often, they are divided according to the operation principle of the drive into two main types such as
There are also several other parameters for classification. For example, they can be divided according to the movement direction into rotational or linear.
Siemens servomotors series
German company has been producing electric motors for quite long time. During this period, the manufacturer managed to develop its own models for almost all necessary industrial tasks.
Siemens servomotors are divided into:
All of them are designed to perform a different range of tasks.
Siemens synchronous motors
Synchronous servomotors are electric motors in which rotation speed of drive and electromagnetic fields of stator are the same. That is, they move synchronously with each other, hence their name.
The features of such devices are excellent accuracy in operation, wide adjustment parameters and a high degree of protection against overloads.
Category includes the following series:
1FT7. It has a compact design. Fully adapted to work with new digital control systems.
SIMOTICS S-1FK2. They are quite multipurpose synchronous motors with excellent work dynamics and compact dimensions. Such drive units have a low inertia and robust protection. They are used in almost all areas of industry.
1FK7. Servomotors series, which has 3 main types. Depending on the frequency inverter which is used. with engine (SINAMICS S 110, 120 and 120 Combi). The presented types also have differences in functionality and tasks. Read Siemens servomotors manuals for more details. This range of models is designed to work with new generations of machines, thanks to the excellent flexibility and optimization. Motors are able to dissipate heat generated by operation without forced ventilation.
SIMOTICS S-1FL6 servomotors for SINAMICS V90. They have good performance and are easy to install. The heat that occurs as a result of work can be dissipated independently through housing. It becomes possible not to install a forced ventilation system.
Synchronous servo drives are perfect combined with frequency converters of the SIMODRIVE 611 and SIMOVERT series.
Siemens asynchronous servomotors
In asynchronous motors, the rotor speed is lower than stator magnetic fields. Therefore, they move at different frequencies, hence asynchronously.
The following series are presented:
1PH8 for SINAMICS S has several models depending on the type of frequency converter that used in pair and performed tasks. Motors are available for collaboration with SINAMICS S 110, and has various models for interfacing with SINAMICS S 120 (for machine tools, cranes, production machines and Combi). Such servomotors can perform a wide range of tasks from work in pumping installations to operation with complex demanding production systems.
1PH2 built-in engines. Represent a short-circuited asynchronous motor. Water is used as cooling. Designed specifically to control spindle speed in lathes.
Advantages of asynchronous motors are their high reliability and stability of work for a low price.
The company also produces linear and moment motors. They include the series:
They are able to perform a variety of special tasks.