Table of Contents
- 1 What is meant by rotating magnetic field?
- 2 How is rotating magnetic field produced in alternator?
- 3 How is a rotating magnetic field produced in a single phase supply?
- 4 What is the speed of rotating magnetic field?
- 5 Who discovered the rotating magnetic field?
- 6 Why is a rotating field system used in preference to a stationary field?
- 7 What causes the rotating magnetic field in a stator?
- 8 How is a rotating magnetic field produced from a polyphase AC supply?
What is meant by rotating magnetic field?
A rotating magnetic field is the resultant magnetic field produced by a system of coils symmetrically placed and supplied with polyphase currents. Rotating magnetic fields are often utilized for electromechanical applications, such as induction motors, electric generators and induction regulators.
How is rotating magnetic field produced in alternator?
A rotating magnetic field is generated when the magnet rotates, and the coil cuts the magnetic lines of force to generate an induced electromotive force, seeing figure 1. Mount the stator and coil on the periphery of the rotor, and a single-phase alternator model is formed, as shown in figure 3.
How rotating magnetic field is generated in a three phase supply explain?
When a 3-phase winding is energized from a 3-phase supply, a rotating magnetic field is produced. The three-phase currents flow simultaneously through the windings and are displaced from each other by 120° electrical. Each alternating phase current produces its own flux which is sinusoidal.
What is rotating magnetic field and conditions?
When a balanced poly phase current flows in the balanced poly phase winding, a rotating magnetic field is produced. The necessary condition for generation of rotating magnetic field is that “the time angle displacement between the currents and space angle displacement between the winding axes must be equal.”
How is a rotating magnetic field produced in a single phase supply?
The magnetic field rotates due to the 120° phase offset in each phase of the power supply. This rotating magnetic field induces a current in the bars of the rotor. The interaction between the stator and rotor magnetic fields causes the rotor to rotate.
What is the speed of rotating magnetic field?
Speed is important to the rotating magnetic field of an AC motor. It is known as “synchronous speed.” This speed is calculated by dividing 120 times the frequency (F) by the number of poles (P). As an example, the synchronous speed for a 2-pole motor operated at 60 Hz is 3,600 RPM.
Which is the rotating part of an alternator?
The stationary part of the alternator, also known as ‘stator’ is a set of wires, or electrical conductors wound in coils over an iron core. The rotor also known as the armature is the movable part of the alternator that produces the rotating magnetic field in three different ways.
How can you make a rotating magnetic field from two phase supply?
In an induction motor, when AC supply is given to the the stator, magnetic flux is produced which is revolving at synchronous speed. This post will explain you in brief about production of rotating magnetic flux for 2 phase as well as 3 phase supply.
Who discovered the rotating magnetic field?
This article presents the life and achievements of this Serbian-American inventor and researcher who discovered the rotating magnetic field, the basis of most alternating-current machinery. Nikola Tesla had 700 patents in the United States and Europe that covered every aspect of science and technology.
Why is a rotating field system used in preference to a stationary field?
Because you would have to draw all the power via slip rings and brush-gear and one could not generate at say 11 kV. That is why a rotating DC field is preferred and why the stator is able to generate at very high voltage levels as the insulation issues are much easier to handle.
What happens when a magnet rotates?
When you rotate a magnet, you are using kinetic energy to move it. This kinetic energy can be converted to electrical energy by taking advantage of the properties of electromagnetism.
How rotating magnetic field is produced in a rotating machine?
When we apply a three-phase supply to a three-phase distributed winding of a rotating machine, a rotating magnetic field is produced which rotates in synchronous speed. In this article, we will try to understand the theory behind the production of rotating magnetic field.
What causes the rotating magnetic field in a stator?
The rotating magnetic field is produced radially around the rotor by the varying currents in the stator windings. The rotating magnetic field induces eddy currents in the squirrel cage’s vertical bars causing it to rotate. The rotation of the rotor and magnetic field are asynchronous.
How is a rotating magnetic field produced from a polyphase AC supply?
In practice, without any external force, a rotating magnetic field can be produced with the help of a polyphase ac supply. When the three-phase uniformly distributed winding suitably wound on the stator is supplied with a 3-phase ac supply, a rotating magnetic field of constant magnitude rotating at synchronous speed is produced.
Why is a 3 phase winding called a rotating magnetic field?
When a 3-phase winding is energized from a 3-phase supply, a rotating magnetic field is produced. This field is such that its poles do no remain in a fixed position on the stator but go on shifting their positions around the stator. For this reason, it is called a rotating field.