Types of Electrical Motors
Used in a wide range of applications within the home and in industrial environments, an electric motor is a device that turns electric energy into mechanical energy.There are basically two kinds of electric motors: alternating current (AC) and direct current (DC). The DC motor is different from AC motor because it uses electricity and a magnetic field to form what is known as torque. Both categories are further divided into different subcategories, according to the functions they perform.
Asynchronous AC Motors
An asynchronous AC motor features an AC transformer accompanied by a rotating secondary, attached to the main source of power. This secondary rotor, which produces the torque, carries the induced current. Used in generators, washing machines, dryers, and water pumps (to name a few), an induction motor is also another name for asynchronous AC motor.
Linear Electric Motors
Comparatively cheaper than rotary electric motors, AC linear electric motors came into use about 100 years age. The linear induction motors have large air gaps, and typically are chosen for material-handling applications, such as an indoor folk lift equipment, because they run quietly and efficiently. Another characteristic of linear electric motors is that they do not have drive gearboxes.
Brushless DC Motors
DC motors motors are used mostly within the industrial settings, mostly because of their speed-torque relationship, which can vary in relation to the form required. DC motors have the ability for continuous application. Industrial applications use DC motors because the speed-torque relationship can be varied to almost any useful form. They can produce more than five times the rated torque, and are suitable for use in equipment such as an industrial generator that is used by hospitals as an emergency alternative to power outage situations.
Limited-Angle DC Motors
The limited-angle DC motor is made to produce torque within a predetermined angle of 180 degrees or less. These devices are used in sophisticated systems such as direct laser mirrors, to position missile-guided radar antenna, and in heat-seeking sensors. Limited-angle DC motors fit multiple applications, particularly those found in military guidance systems and munitions.
Another example of a DC motor, the stepper motors is mostly used within the industrial automation process. It is constructed to employ computerized a control system in stepping the rate of the rotation of the motor. This procedure helps control the robotic arm of the automation mechanism, for instance. Stepper motors are designed to be very accurate, a characteristic that's critical to the automation process.