INTRODUCTION Circulating currents are produced by the induced voltage differences between parallel strands in a bar due to different linkage magnetic flux. In large synchronous generator with high power density, the Roebel bars are used for the stator windings in which strands in a bundle are completely transposed in slot region by different arrangement. By the use of this procedure, the overall physical position of each strand in a bundle is the same. Therefore, the both main and leakage fluxes
comes from the rotor conductors. The revolving magnetic earth produced in the stator cuts across the conductive bars of the rotor and induces an e.m.f. The windings of the rotor which is being used due to the force of an external resistance tend to be directly shorted or closed which will lead in changing the direction of the rotor current in the other direction of the rotating magnetic field which is resulted from the stator and at the end a torque will be resulted in the rotor. As a reult, the rotor
Buyer’s Spotlight: Electromagnetic vs. Electrostatic Loudspeakers In this buyer’s spotlight the physics behind electromagnetic and electrostatic loudspeakers will be used to compare, contrast and justify which is best option for sound section of an integrated home theatre system. (main points, headings) What physics principles are behind: Electromagnetic loudspeakers convert the electrical signal back into sound by the voice coils vibrating. The original sound is recorded by a microphone and is amplified
industries is provided by three phase induction motors because of its simple and rugged construction, low cost, good operating characteristics, absence of comutator and good speed regulation. In three phase induction motor the power is transferred from stator to rotor winding through induction. The Induction motor is also called asynchronous motor as it runs at a speed other than the synchronous speed. Induction motor is also called as asynchronous motor because it runs at a speed less than synchronous
Pole changing • So briefly the pole changing can be altered by using multiple stator windings, method of consequent poles and pole amplitude manipulation. 2- Supply frequency control 3- Rotor resistance control • This method is only done in wound rotor motors, by adding resistance to the rotor circuit in the rotor bars, this will affect the torque-speed curves greatly. This method is affective and not expensive. 4- Stator voltage control 5- Slip recovery
stage enlistment engine the power is exchanged from stator to rotor twisting through acceptance. The Enlistment engine is likewise called offbeat engine as it keeps running at a speed other than the synchronous speed. Like some other electrical engine enlistment engine additionally have two primary parts to be specific rotor and stator. A 3-stage enlistment engine has two principle parts (I) stator and (ii) rotor. The rotor is isolated from the stator by a little air-crevice which ranges from 0.4 mm
suspensions or emulsion. The shearing is the mechanism in the colloidal mill. By the stator and the rotor present in the cylindrical vessel of the colloidal mill the shearing take place and the reduction of the particles takes place. BASIC PARTS, CONSTRUCTION, PRINCIPLE AND WORKING OF THE COLLOIDAL MILL Basic parts It consists of an inlet hopper which is used to feed the material into the mill. It consists of a rotor and stator which are used to reduce the particles size by applying the shearing force. It
Synchronous Motor: Supposed in light of the fact that rotor tries to match with the magnetic field in the stator. It has the stator of an induction engine, and the rotor of a dc engine. A synchronous engine is an AC engine, which keeps running at steady speed altered by recurrence of the framework. It requires coordinate current (DC) for excitation and has low beginning torque, and consequently suited for applications that begin with a low load, for example, air compressors, recurrence changes
speed is dependent on the voltage and the connection. Second type is a induction motor which runs slightly slower than the supply frequency. The magnetic field on the rotor of the motor is created by an induced current . when the rotor rotates, the stator conductors are cut by the magnetic flux hence the reason an induced E.M.F is produced by them, because the magnetic poles are alternative N and S , they induced an E.M.F and hence current is armature conductors which first flow in one direction and
Magnetic Levitation and Propulsion through Synchronous Linear Motors MagLev technology is entirely different from any form of transportation in operation today, but the basic principles that lie at the foundation are not beyond the understanding of the beginning electricity and magnetism student. It is in the application of these principles to design and optimize an actual train that things get hairy. The basic idea has been researched since the mid-sixties, but it is only now that economically
There are many uses for magnets. One of the more interesting uses of magnets is how they are used to both suspend, and propel trains. In this day and age, there are not many vehicles that can match the performance of an airplane, in terms of being able to transport a large number of passengers in such a short amount of time. The average train has the ability to carry a large number of passengers, but is not as good when the need for speed arrives. Maglev trains are a solution to this problem
combustor and turbine blades outward towards the stream of bypass air. This is accomplished by stators, or channels that direct the air flow. There are stators in several other places in the engine, but their function is to stop the rotational momentum of the air and force it to fly straighter. After having turned the turbine blades, the air is given a spiraling motion which decreases its velocity. The stators correct this by channeling the air towards the nozzle so that it can be expelled as exhaust
The first, a static component which consists of magnetic materials and electrical conductors to generate magnetic fields of a desired shape, is known as the stator. The second, which also is made from magnetic and electrical conductors to generate shaped magnetic fields which interact with the fields generated by the stator, is known as the rotor. The rotor comprises the moving component of the motor, having a rotating shaft to connect to the machine being driven and some means of maintaining
centerline of the south pole from another magnetic field (Fitzgerald et al., 1981). The opposing magnetic fields in a motor are generated by two separate concentrically oriented components, the stator and a rotor (Figure 2-5). Figure 2 5 Rotor and stator schematics of a three-phase DC motor The stator is the stationary component while the rotor is the rotational component of the motor. Usually magnetic fields are created when an electric current is applied to a set of conductive wires wound together
a rotor. This is the part that spins. The armature can be either a permanent magnet or an electromagnet. * Stator - This is the part that doesn't move. The rotor spins in the magnetic field contained in the stator. HOW WORKS A MOTOR? The force that that turns the armature comes from the magnetic field of the armature trying to line up with the external magnetic field of the stator. This force is called torque. This torque will cause the armature to turn until its magnetic field is aligned
driven by a three phase inverter in which the devices are triggered with respect to the rotor position as shown in Fig. 3. The phase A terminal voltage with respect to star point of the stator V_an is given as, V_an =R_(a ) i_a +L_a d_ia/dt +e_an (10) where R_(a ) is the stator resistance, L_a is the phase inductance,e_an is the back emf,i_a is the phase current of the "A" phase. Similar equations can be written for the other two phases as
An armature rotates inside a magnetic field[3] in a DC motor[1].Based on the fact of the fundamental operating principle of a DC motor that whenever a current carrying conductor is placed inside a magnetic field, the conductor experienced mechanical force. All kinds of DC motors work on the same principle. Hence for developing a DC motor, it is important to establish a magnetic field. The magnetic field is established by means of a magnet[2].The magnet can be any sorts for instance it might be electromagnet
Task 1 (P4) 1. Select two main types of gas turbine engines and state their pros and cons with respect to their operation, construction and installation arrangement Gas turbine engines are broken into four different types, the turbojet engine, the turbofan engine, the turboprop engine, and the turboshaft engine. Turbofan and turboprop engines will only be given detailed study. Turboprop Engine Turboprop engine is almost the same as turbofan since it is also equipped with a fan on the front section
brought back up to its original value. Alternators used in central power stations also control the field current to regulate reactive power and to help stabilize the power system against the effects of momentary faults. Often there are three sets of stator windings, physically offset so that the rotating magnetic field produces a three phase current, displaced by
Tesla in 1888. In the article, How Tesla will change the world, author Tim Urban (2015) explains how an induction motor works: “AC stands for alternating current, and induction means there’s no physical contact between the rotor and the stator—electricity in the stator generates a rotating