Electric motor
Electric motor, some of a class of devices that convert electrical energy to mechanical energy, usually by using electroAc Induction Motor magnetic phenomena.
What is a power motor?
How can you bring stuff in motion and keep them moving without moving a muscle mass? While steam engines create mechanical energy using scorching steam or, more specifically, steam pressure, electrical motors use electric energy as their supply. For this reason, electrical motors are also known as electromechanical transducers.
The counter piece to the electric engine is the generator, that includes a similar structure. Generators transform mechanic movement into electric power. The physical basis of both procedures may be the electromagnetic induction. In a generator, current is definitely induced and electrical energy is created when a conductor is at a moving magnetic field. Meanwhile, in an electric motor a current-having conductor induces magnetic fields. Their alternating forces of attraction and repulsion produce the basis for generating motion.
How does an electric motor work?
Motor housing with stator
Motor housing with stator
In general, the heart of a power motor includes a stator and a rotor. The word “stator” comes from the Latin verb “stare” = “to stand still”. The stator may be the immobile part of a power motor. It really is firmly attached to the equally immobile casing. The rotor on the other hand is installed to the engine shaft and can move (rotate).
In case of AC motors, the stator includes the so-called laminated core, which is wrapped in copper wires. The winding functions as a coil and generates a rotating magnetic field when current is certainly flowing through the wires. This magnetic field produced by the stator induces a current in the rotor. This current then generates an electromagnetic field around the rotor. Consequently, the rotor (and the attached motor shaft) rotate to follow the rotating magnetic field of the stator.
The electric electric motor serves to use the created rotary motion in order to drive a equipment unit (as torque converter and speed variator) or even to directly drive an application as line motor.
What forms of electric motors can be found?
All inventions began with the DC motor. Nowadays however, AC motors of various designs are the mostly used electric motors in the industry. They all have a common result: The rotary motion of the motor axis. The function of AC motors is founded on the electromagnetic operating theory of the DC electric motor.
DC motors
As with most electric motors, DC motors consist of an immobile component, the stator, and a moving element, the rotor. The stator consists either of a power magnet utilized to induce the magnetic field, or of long lasting magnets that consistently generate a magnetic field. Within the stator 
is where the rotor is definitely located, also called armature, that is wrapped by a coil. If the coil is connected to a way to obtain direct current (a electric battery, accumulator, or DC voltage supply device), it creates a magnetic field and the ferromagnetic core of the rotor turns into an electromagnet. The rotor is usually movable installed via bearings and may rotate to ensure that it aligns with the attracting, i.e. opposing poles of the magnetic field – with the north pole of the armature reverse of the southern pole of the stator, and the other method round.
In order to set the rotor in a continuing rotary movement, the magnetic alignment should be reversed again and again. This is attained by changing the current direction in the coil. The motor has a so-known as commutator for this purpose. Both supply contacts are linked to the commutator and it assumes the duty of polarity reversal. The changing attraction and repulsion forces ensure that the armature/rotor proceeds to rotate.
DC motors are mainly utilized in applications with low power rankings. These include smaller tools, hoists, elevators or electrical vehicles.
Asynchronous AC motors
Instead of direct current, an AC motor requires three-phase alternating electric current. In asynchronous motors, the rotor is usually a so-called squirrel cage rotor. Turning results from electromagnetic induction of this rotor. The stator consists of windings (coils) offset by 120° (triangular) for every phase of the three-phase current. When connected to the three-stage current, these coils each build-up a magnetic field which rotates in the rhythm of the temporally offset line frequency. The electromagnetically induced rotor is usually carried along by these magnetic areas and rotates. A commutator as with the DC engine is not needed in this way.
Asynchronous motors are also known as induction motors, because they function only via the electromagnetically induced voltage. They run asynchronously because the circumferential speed of the electromagnetically induced rotor by no means reaches the rotational swiftness of the magnetic field (rotating field). For this reason slip, the effectiveness of asynchronous AC motors is leaner than that of DC motors.
More on the framework of AC motors / asynchronous motors and on what we offer
AC synchronous motors
In synchronous motors, the rotor is equipped with permanent magnets instead of windings or conductor rods. In this manner the electromagnetic induction of the rotor can be omitted and the rotor rotates synchronously without slide at the same circumferential acceleration as that of the stator magnetic field. Efficiency, power density and the feasible speeds are thus considerably higher with synchronous motors than with asynchronous motors. However, the design of synchronous motors can be much more complex and time-consuming.
More details about synchronous motors and our portfolio
Linear motors
In addition to the rotating devices that are mainly used on the market, drives for motions on straight or curved tracks are also required. Such motion profiles occur mainly in machine tools as well as positioning and handling systems.
Rotating electric motors can also convert their rotary movement into a linear movement with the aid of a gear unit, we.e. they can cause it indirectly. Often, however, they do not have the necessary dynamics to realize particularly demanding and fast “translational” movements or positioning.
This is where linear motors come into play that generate the translational motion directly (direct drives). Their function can be produced from the rotating electrical motors. To do this, imagine a rotating engine “opened up”: The previously circular stator becomes a flat travel distance (monitor or rail) which is definitely protected. The magnetic field then forms along this path. In the linear electric motor, the rotor, which corresponds to the rotor in the three-phase electric motor and rotates in a circle there, is stopped the travel distance in a straight line or in curves by the longitudinally moving magnetic field of the stator as a so-called carriage or translator.
More information about linear motors and our drive solutions