What is servo motor

These are backed by comprehensive support that extends from prototyping to commercial production and after-sales service.

ASPINA can offer solutions that are tailored to suit the functions and performance demanded by a diverse range of industries, applications, and customer products, as well as your particular production arrangements. ASPINA supports not only customers who already know their requirements or specifications, but also those who are facing problems at early stages of development.

Do you struggle with the following concerns? Small brushless motors. What are the disadvantages of brushless DC motors? And how can you use them in your application? And how can they be overcome? Contact us. What is a servo motor? Definition of servo motor. Servo motor Stepper motor. Don't have detailed specifications or design drawings yet, but need advice on motors? Don't have anyone in-house with expertise in motors and can't identify what sort of motor will work best for your new product?

Want to focus your resources on core technology, and outsource drive systems and motor development? Want to save the time and effort of redesigning existing mechanical components when replacing your motor?

Need a custom motor for your product, but been declined from your usual vendor? Can't find a motor that gives you the control you require, and about to give up hope? List of the same series columns Small brushless motors What are the disadvantages of brushless DC motors? How do brushless DC motors work? The need for a drive circuit explained Do brushless DC motors require a drive circuit? What is an electric motor? What is a brushless DC motor?

How are stepper motors controlled? As you will learn within this lesson, servo motor applications are most commonly used in closed loop systems where precise position control commonly found in industrial and commercial applications.

Together with the recently RealPars published blog post, what is a Stepper Motor and How it Works, and this lesson, you will learn about motion control using different types of motors available, primarily stepper and servo motors. Servo motors are part of a closed-loop system and are comprised of several parts namely a control circuit, servo motor, shaft, potentiometer, drive gears, amplifier and either an encoder or resolver.

A servo motor is a self-contained electrical device, that rotate parts of a machine with high efficiency and with great precision. The output shaft of this motor can be moved to a particular angle, position and velocity that a regular motor does not have. The controller is the most important part of the Servo Motor designed and used specifically for this purpose.

The servo motor is a closed-loop mechanism that incorporates positional feedback in order to control the rotational or linear speed and position. The motor is controlled with an electric signal, either analog or digital, which determines the amount of movement which represents the final command position for the shaft.

A type of encoder serves as a sensor providing speed and position feedback. This circuitry is built right inside the motor housing which usually is fitted with gear system. Types of Servo Motors are classified into different types based on their application, such as the AC servo motor, and DC servo motor.

There are three main considerations to evaluate servos motors. First based on their current type — AC or DC, and secondly on the type of Commutation used, whether the motor uses brushes and the third type of consideration is the motors rotating field, the rotor, whether the rotation is synchronous or asynchronous. AC or DC consideration is the most basic classification of a motor based on the type of current it will use.

Looking at it from a performance standpoint, the primary difference between AC and DC motors is in the inherit ability to control speed. And in an AC motor, speed is determined by the frequency of the applied voltage and the number of magnetic poles. While both AC and DC motors are used in servo systems, AC motors will withstand higher current and are more commonly used in servo applications such as with robots, in-line manufacturing and other industrial applications where high repetitions and high precision are required.

Brushed or brushless is the next step. A DC Servo Motor is commutated mechanically with brushes, using a commutator, or electronically without brushes. Brushed motors are generally less expensive and simpler to operate, while brushless designs are more reliable, have higher efficiency, and are less noisy. A commutator is a rotary electrical switch that periodically reverses the current direction between the rotor and the drive circuit. It consists of a cylinder composed of multiple metal contact segments on the rotor.

While the majority of motors used in servo systems are AC brushless designs, brushed permanent magnet motors are sometimes employed as servo motors for their simplicity and low cost.

The most common type of brushed DC motor used in servo applications is the permanent magnet DC motor. Brushless DC motors replace the physical brushes and commutator with an electronic means of achieving commutation, typically through the use of Hall effect sensors or an encoder. AC motors are generally brushless, although there are some designs—such as the universal motor, which can run on either AC or DC power, that do have brushes and are mechanically commutated.

And the final classification to consider is whether the servo motor application will use a synchronous or asynchronous rotating field. While DC motors are generally categorized as brushed or brushless, AC motors are more often differentiated by the speed of their rotating synchronous or asynchronous field. If we recall from the AC-DC consideration, that in an AC motor, speed is determined by the frequency of the supply voltage and the number of magnetic poles. This speed is referred to as the synchronous speed.

However, the speed of an asynchronous motor can be varied utilizing several control methods such as changing the number of poles, and changing the frequency just to name a couple.

A software interface with the control electronics also allows precise parameterization and programming for actuation of the motor, which provides a high degree of dynamism and individuality.

In particular, additive processes in plastics production as well as automation and robotics solutions can be implemented efficiently and enable maximum precision for production processes.

The term servo motor must be viewed historically. The name comes from earlier areas of use in which the motors were used as support drives auxiliary drives. Due to the rapid continued development of components, e. By virtue of the way in which they work, servo motors have a special feature in that torque, speed and position can be controlled precisely, and therefore very fine and dynamic movements are made possible.

It is always connected to a servo controller , which converts the signals of a control unit, which nowadays is mostly digital, and therefore allows precise programming. In the manufacturing industry, servo motors are used in all types of automation solutions, e. Modern servo motors are actuated by a servo controller — both together form the servo drive.

With this combination, the motor can be operated with very dynamic movements, high effective torque and high power density. Due to the way it works, it is also particularly energy efficient and can achieve high nominal power with relatively small deviation. Costs are therefore saved on multiple levels, which are reflected in better economic efficiency of servo-assisted drive systems.

The greatest strength of the servo motor and the way it works, however, does not emerge until it interacts with the servo controller. Together, software-supported programming is possible, which ensures outstanding precision. Predefined torque, position and speed can be controlled with maximum precision and dynamically adapted to the required movement.

Very complex machine processes can therefore be implemented. Since servo motors are generally subjected to high loads, effective cooling is indispensable in many cases. This can be implemented in different ways:. Air cooling can be an option, but has the disadvantage of taking up a relatively large amount of space and is maintenance-intensive, due to the regular cleaning required. Failure to clean leads to reduced cooling capacity and the machine can fail.

A water-cooled servo motor solution can be implemented with significantly less space and also requires less maintenance. In addition, a compact, side-by-side arrangement of multiple servos is possible, without heating each other with the waste heat produced.

The same applies to cooling with oil, although here the cooling capacity is somewhat lower. Summarizing, water cooling is the ideal solution, especially for sophisticated areas of use.