Introduction:
There are two types of motors dc motors and AC induction motors, the two motors have both the same function to convert the electrical energy into mechanical energy but the difference is the type pf power which is used in each motor the DC motors use the direct current while the AC induction motors use the alternating current. The speed of the two motors is varied the DC motor use armature current to control it while the AC induction motor is being controlled by the frequency. The AC motors is classified into two types the first type is induction motor which is operated by applying the magnetic field on the rotor while the other type is synchronous motor which is rotating at the supply frequency but the speed and velocity of synchronous motor is higher than the induction motors.
There are two types of induction motors single phase induction motor and 3-phase induction motor, first will talk about single phase induction motor it is used in small applications compared to the 3-phase induction motor so it can be used in houses and shops as in our daily life machines as: fans, vacuum cleaner and pumps, The single is different than 3-phase as it has no torque starting. The second type for the induction motor is The 3-phase induction motor is one of the most important electric motors used due to its good properties as it is so simple, best construction and lower cost, also it can be started by self so no need for an external device to start it and finally it has high reliability and high thermal efficiency so it is the 3-phase induction motor has many characteristics which is better than the single phase induction motor. We are going to talk in this research about the three phase induction motor and its machine constructio...
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... a little current. In induction motors, this present 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 speed will not reach the synchronous speed of the r.m.f in the stator. If the speeds match, there should be no e.m.f. generated in the rotor, no present should be flowing, and consequently no torque should be generated. The difference between the stator (synchronous speed) and rotor speeds is known as the slip.
The Wankel rotary engine named after the designer, Felix Wankel, was engineered in the early 1930’s. The rotary engine was unlike the conventional four stroke internal combustion engines and lacked the need for pistons, valves and camshafts. With only three moving parts involved in the design, this engine showed great promise in reliability and efficiency. The first Wankel rotary model was shown in 1960, not as an engine, but as a pump drive. Instead of the very complicated system involved in a conventional reciprocating piston engine, the wankel engine incorporated triangular “rotors” (see figure 1) that rotate within an epitrochoidal chamber around an eccentric shaft. Not only is this engine much more simple (only 3 moving parts rather
...late 17th century, and beginning of the 18th century, transportation was favored by American society so much, the wealthier would hire chauffer’s to take people places. So not only did the motor produce a better and more efficient life style, it also created a huge business industry, as we know it today called, “valeting”. The actual motor worked like this. “Two cups filled with mercury would contain a magnet and a wire with one being fixed and the other free to move. Whenever a current was passed through the wire, the free moving magnet or wire would revolve around its fixed partner due to the electromagnet forces being produced.” (History of Innovation). This first motor was a prime example of the fact that movement could be created by electricity and electricity could be created by friction. This motor was the most useful and applicable invention in the 1800’s.
The idea of such a machine tantalized Tesla for years until one day at the age of 24 when he was living in Budapest working for the Central Telephone Exchange he had an epiphany and began making sketches that would soon develop into the world's first induction motor.
The Wankel Engine’s efficiency comes from the design where instead of having multiple pistons doing one of the four strokes of a four stroke engine (intake, compression, combustion, exhaust) at a time, it has a single triangular shaped rotor doing all four at once. And because the rotor rotates in a circular pattern there in no stopping to change the direction of the rotor unlike pistons which have to change directions with every stroke, this also makes the Wankel Engine smoother and better balanced than traditional internal combustion engines. And also because there is usually only one or two rotors, depending on the engine, they are much more compact than the traditional inline or v-block designs.
Firstly, I would like to discuss the beginning of technology and how it has quickly changed. From 1822, the first rotating device that used electromagnetism that was built by Peter Barlow. To then, 12 years later in May 1834, the first actual working electric motor was built by Moritz Jacobi. 4 years later, in September 1838, Jacobi then improved the first electric motor, it was now powerful enough to drive a boat across a (wide) river, filled with 14 people. Although it wasn’t until 1839/1840 that other inventors, worldwide, were able to build motors that were of a higher performance. However, it wasn’t until 1868, that the first power station was built. The power station was used to power; lights, heating, inventions that produced hot water, an elevator, life saving devices and farm buildings. It wasn’t although until 1882, that the public power station started operation. Therefore technology advances, are our friend.
A direct current in a set of windings creates a polar magnetic field. A torque acts on the rotor due to its relation to the external magnetic field. Just as the magnetic field of the rotor becomes fully aligned with the external magnetic field, the direction of the current in the windings on the armature reverses, thereby reversing the polarity of the rotor's electromagnetic field. A torque is once again exerted on the rotor, and it continues spinning.
Energy efficient motors use more copper and iron than regular motors. They also consume less energy than regular motors.
Have you ever walked into a room, turned on a light, and wondered, “Who gave us the ability to do this?” Nikola Tesla is the man’s name. He invented Alternating Current, or AC, which is the electrical system that we use to power our world today. In this paper, I will be describing a few of Nikola Tesla’s innovations and how they inspired and impacted our way of life.
To understand how this motor works, we must understand the relationship between electricity, and magnetism, or simply put, electromagnetism. Direct electric current in a simple description: There are two requirements for current flow. The first is a source of electrical potential energy or EMF (electro motive force). The second is a conductor that provides a complete loop to carry the current. The reason a conductor will conduct is found at the atomic level.
There are hundreds of occupation around the world, few of which anyone would want to do. Being an electrician is one of them. Electrician keep lighting, electrical system around a building and generator working. Being an electrician can also be dangerous. You can die if you get Electrocuted by touching cables that have running current through them.
Alternating current is always changing in direction and amplitude. The current flow in alternating current changes in even intervals. Ac usually changes in power and direction. The vast majority of power supplied for households and big business is alternating current. This is because of the ease of generating alternating current in alternators. The main concept of alternators is moving a conductor through magnetic lines. The change in the magnetic field around the conductor or vice versa makes electrons move. When you have physically moved either the conductor or magnet in a complete 306-degree circle you have produced one sine wave or one complete cycle. The amount of time it takes to complete one cycle is referred to as a period. The frequency of an alternating sine wave is the amount of cycles per second. Frequency is measured in hertz. One hertz is equivalent to one cycle per second. The frequency coming out of your electrical plug at home is 60 Hz. The peak value in a sine wave is the top voltage level away from zero. The peak-to-peak voltage value is referring to difference between the positive peaks value to the negative peak value. The effective or rms value of a sine wave is the actual amount you would use or measure using a multi-meter. In three-phase alternating current there are three different coils or conductors that produce three different sine waves.
electricity as the “fuel” instead of gasoline or some other combustible fuel. The electric motor in
... that conversion device; converting linear electric current into a series of alternating pulses that caused the rotor to rotate. Because these conversion devices always used some energy in the process of linear to rotary motion, Tesla’s idea of a commutator-less motor seemed to Poschl that Tesla would be cheating Nature.” (TESLA) Poschl intended that what he said to Tesla would change his resolve from what would be Alternating Current (AC). Instead Tesla is fired up to this as if he were accepting a challenge.
In 1831, using his "induction ring", Faraday made one of his greatest discoveries - electromagnetic induction: the "induction" or generation of electricity in a wire by means of the electromagnetic effect of a current in another wire. The induction ring was the first electric transformer. In a second series of experiments in September he discovered magneto-electric induction: the production of a steady electric current. To do this, Faraday attached two wires through a sliding contact to a copper disc. By rotating the disc between the poles of a horseshoe magnet he obtained a continuous direct current. This was the first generator. From his experiments came devices that led to the modern electric motor, generator and transformer.
Electrical motors function by converting electrical energy into mechanical energy by using the energy stored in the magnetic field (Sarma, 1981). The mechanical energy (torque) is produced when opposing magnetic fields try to lineup. Therefore, the center line of the north pole of a magnetic field is directly opposite to the 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).