An electromagnet is a type of magnet in which the magnetic field is produced by the flow of an electric current. If the flow of electrical current also disappears magnetic field disappears and the effect arising. Characteristics of electromagnets
The electromagnet is a simple piece of metal wire wound in a coil. A cylindrical coil with the wire coiled helix-shaped (like a corkscrew corkscrew-shaped) generally named solenoid; a solenoid would be a closed toroid.
May occur if stronger magnetic fields within the coil becomes a core of a ferromagnetic or paramagnetic material,…
Foucault currents are the currents induced in masses of conducting metal that are immersed in a variable magnetic field or that, in motion, through a constant or variable magnetic field. In any case, it is the variation of the magnetic flux that generates these currents. The phenomenon was discovered by the French physicist Jean Bernard Léon Foucault in 1851.
In high frequency: using cores with magnetic materials that have low electrical conductivity (such as ferrite).
Foucault currents create energy losses through the Joule effect. More specifically, these currents transform…
Altern current motors are electric motors that are powered by alternating current. Electric motors convert electrical energy into mechanical rotation energy through the mutual action of magnetic fields.
There is a wide variety of altern current motors, among which the following basic types stand out:
- The universal motor that can also be direct current.
- The synchronous motor. In this type of electric motor the speed of rotation is constant and depends on the frequency.
- The asynchronous motor. It is a three-phase motor.
In some cases, such as…
The current carrying excitation winding in the stator generates a magnetic field, which is amplified by the iron sheet package and grouped into defined poles. The same happens in the winding of the armature coil downstream. Depending on how the poles are established, this magnetic field created by the stator of the universal motor causes the rotor to drag behind or push it in front of it. In this case, the coils must be inverted in each half revolution (for machines with a pair of poles), for which a switch is necessary.
Considering a "single pole" version, both magnetic fields are perpendicular…
A linear motor is an asynchronous electric motor that has been developed so that instead of generating a rotating torque it generates a linear displacement. To get it distributes your stator and its rotor distributed differently.
The most common mode of operation is like a Lorentz actuator. In this mode the applied force is linearly proportional to the electric current and to the magnetic field
Linear motors are divided into two main groups:
- Slow acceleration linear motors used in Sky Train transport, Maglev, etc.
- Quick acceleration linear motors used in…
A squirrel cage rotor is the rotating part of the common squirrel cage induction motor. The squirrel-cage motor is a type of AC motor.
This type of rotor consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. In operation, the non-rotating stator winding is connected to an alternating current power source; the alternating current in the stator produces a rotating magnetic field. The rotor winding has a current induced by the stator field, and produces its own magnetic field. The interaction of the two magnetic field sources produces torque…
The universal motor is a type of electric motor that can operate both with direct current and with single-phase alternating current.
Its constitution is similar to that of a direct current series motor, although with some modifications:
The polar nuclei, and the entire magnetic circuit, are built with silicon iron plates isolated and stacked to reduce energy losses by parasitic currents. These currents occur because of magnetic flux variations when connected to an alternating current network.
It has a lower number of turns in the inductor to not magnetically saturate…
In physics, electricity is a generic term that encompasses a whole set of phenomena that are the manifestation of the presence of a movement of electric charges. We can apply the term electricity to phenomena known as lightning or static electricity but also to other such as the electromagnetic field or electromagnetic induction. The word also serves to designate the branch of physics that studies electrical phenomena and their applications.
In the following sections we will study electricity from a physical point of view…
An electric generator is a machine that transforms rotational mechanical energy into electrical energy. In this sense, it works in the opposite sense of how an electric motor works.
An electric generator is any device capable of maintaining an electrical potential difference (voltage) between two points, called poles or terminals. Electric generators are electrical machines designed to transform mechanical energy into electrical. This transformation is achieved by the action of a magnetic field on the electric conductors arranged in coils on a sheet metal frame. If a relative movement…
Electric motors of direct current work thanks to the properties of the magnets and to the magnetic field that is generated when circulating an electric current by a conductor.
As we well know, the main characteristic of magnets is that they have a south pole (negative) and a north pole (positive). In two different magnets the poles of different sign attract each other and the poles of the same sign repel each other.
The electric motor is an electrotechnical machine that converts electrical energy into mechanical energy. That is, when the electric motor is connected to the proper power source, it begins to rotate, which also begins to rotate the machine or the machine associated with it. That is, it works inversely to the electric generator, which produces electrical energy with mechanical energy.
The electric motor was made possible thanks to the discoveries of Franz Ernst Neumann and James Clerk Maxwell. His discoveries were published in the years 1841 and 1873.
The electric motors can be…
The armature is the part of an electric machine, magnetically coupled to the inductor, where an electromotive force is generated by induction.
The armature is the rotor in DC machines and the stator in synchronous AC machines.
The term induced term varies depending on the context in which it is used. It is usually linked to the electricity sector, electric machines and motors. Electric machines and motors
If we are talking about electric machines and electric motors. In this context the armature is the part of the rotating machine where the transformation of electrical…
The rotor is the component that turns on an electric machine. The same definition is valid whether the electric machine is an electric motor or an electric generator. The rotor together with its together with its fixed counterpart, the stator, form the fundamental set for the transmission of power in motors and electrical machines in general.
The rotor is formed by an axis that supports a set of coils wound on a magnetic core. This axis rotates inside a magnetic field created either by a magnet, an electromagnet or by passing through another set of coils, wound on some polar pieces.…
An asynchronous motor is an electric motor powered by alternating current. It is, therefore, what we call an AC motor. This type of engine is also known as an induction motor.
The asynchronous motor is based on the currents induced in the rotor from the rotating magnetic field of the stator. That's why it's called an induction machine. As to be able to induce an electric current in the rotor it is necessary that the rotor is subjected to a variation of the magnetic flux generated by the stator at the frequency of power, or synchronism, the rotor is demagnetized when it reaches the synchronism,…
A direct current motor (DC motor), or simply a continuous motor or direct current motor, is a rotating electric malternating currenthine that transforms electrical energy in the form of direct current into mechanical energy through electromagnetic interalternating currenttions.
Virtually all electric motors are reversible, that is, they can transform mechanical energy into electrical energy functioning as dynamos. direct current motors base their operation on the Lorentz law, also called Laplalternating currente's law when it is applied to a conductor, as is the case of motors. Applications…
The electric motors can be distinguished between them according to the type of power supply:
- Electric motors of direct current. The DC electric motor can be, in turn, a permanent induction motor or a continuous induction motor. In addition to these more general classifications there are also other more modern types of engines such as stepper motors and linear motors.
- Electric motors of alternating current. The AC motor can be classified as universal motor, synchronous motor or asynchronous motor.
The classic division is between direct current (DC) and alternating…