ELECTROSTANDARDS PHASE II PDF

The IEC Type 2 connector is used for charging electric cars within Europe. Electric power is provided as single-phase or three-phase alternating current ( AC), or direct current (DC). For DC charging, the Combo 2 socket (Type 2 supplemented with 2 DC pins) shall become standard in cars, replacing Type 4. General Info: Electro Standards Laboratories is an engineering, design and ESL is Phase II SBIR awarded and is based in Cranston, R.I.; BBB Rating: A+. 95 Employees Phase 2 STTR Electro Standards Laboratories proposes to meet the requirements with mechanical wav.

Author: Morisar Votaur
Country: Dominica
Language: English (Spanish)
Genre: Technology
Published (Last): 13 September 2006
Pages: 198
PDF File Size: 17.38 Mb
ePub File Size: 18.94 Mb
ISBN: 359-4-76920-626-4
Downloads: 10720
Price: Free* [*Free Regsitration Required]
Uploader: Taugore

An electric motor is an electrical machine that converts electrical energy into mechanical energy.

Type 2 connector – Wikipedia

Most electric motors operate through the interaction between the motor’s magnetic field and winding currents to generate force in the form of rotation. Electric motors can be powered by direct current DC sources, such as from batteries, motor vehicles or rectifiers, or by alternating current AC sources, such as a power grid, inverters or electrical generators. An electric generator is mechanically identical to an electric motor, but operates in the reverse direction, accepting mechanical energy such as from flowing water and converting this mechanical energy into electrical energy.

Electric motors may be classified by considerations such as power source type, internal construction, application and type of motion output. In addition to AC versus DC types, motors may be brushed or brushlessmay be of various phase see single-phasetwo-phaseor three-phaseand may be either air-cooled or liquid-cooled.

General-purpose motors with standard dimensions and characteristics provide convenient mechanical power for industrial use. The largest electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings reaching megawatts. Electric motors are found in industrial fans, blowers and pumps, machine tools, household appliances, power tools and disk drives.

Small motors may be found in electric watches. In certain applications, such as in regenerative braking with traction motorselectric motors can be used in reverse as generators to recover energy that might otherwise be lost as heat and friction.

Electric motors produce linear or rotary force torque and can be distinguished from devices such as magnetic solenoids and loudspeakers that convert electricity into motion but do not generate usable mechanical force, which are respectively referred to as actuators and transducers. The first electric motors were simple electrostatic devices described in experiments by Scottish monk Andrew Gordon and American experimenter Benjamin Franklin in the s.

The law described the production of mechanical force by the interactions of an electric current and a magnetic field. The conversion of electrical energy into mechanical energy by electromagnetic means was demonstrated by English scientist Michael Faraday in A free-hanging wire was dipped into a pool of mercury, on which a permanent magnet PM was placed. When a current was passed through the wire, the wire rotated around the magnet, showing that the current gave rise to a close circular magnetic field around the wire.

Though Barlow’s wheel was an early refinement to this Faraday demonstration, these and similar homopolar motors remained unsuited to practical application until late in the century. After Jedlik solved the technical problems of continuous rotation with the invention of the commutatorhe called his early devices “electromagnetic self-rotors”. Although they were used only for teaching, in Jedlik demonstrated the first device to contain the three main components of practical DC motors: The device employed no permanent magnets, as the magnetic fields of both the stationary and revolving components were produced solely by the currents flowing through their windings.

After many other more or less successful attempts with relatively weak rotating and reciprocating apparatus Prussian Moritz von Jacobi created the first real rotating electric motor in May It developed remarkable mechanical output power.

His motor set a world record, which Jacobi improved four years later in September The first commutator DC electric motor capable of turning machinery was invented by British scientist William Sturgeon in The motors ran at up to revolutions per minute, and powered machine tools and a printing press. Several inventors followed Sturgeon in the development of DC motors, but all encountered the same battery cost issues.

  IRU 3037 PDF

Electric motor – Wikipedia

No electricity distribution system was available at the time. No practical commercial market emerged for these motors. InJedlik built a device using similar principles to those used in his electromagnetic self-rotors that was capable of useful work. A major turning point came inwhen Antonio Pacinotti first described the ring armature.

This featured symmetrically-grouped coils closed upon themselves and connected to the bars of a commutator, the brushes of which delivered practically non-fluctuating current. InFrank Julian Sprague invented the first practical DC motor, a non-sparking device that maintained relatively constant speed under variable loads.

Other Sprague electric inventions about this time greatly improved grid electric distribution prior work done while employed by Thomas Edisonallowed power from electric motors to be returned to the electric grid, provided for electric distribution to trolleys via overhead wires and the trolley pole, and provided control systems for electric operations. This allowed Sprague to use electric motors to invent the first electric trolley system in —88 in Richmond, Virginiathe electric elevator and control system inand the electric subway with independently-powered centrally-controlled cars.

The latter were first installed in in Chicago by the South Side Elevated Railroadwhere it became popularly known as the ” L “.

Sprague’s motor and related inventions led to an explosion of interest and use in electric motors for industry. The development of electric motors of acceptable efficiency was delayed for several decades by failure to recognize the extreme importance of an air gap between the rotor and stator.

Electric motor

Efficient designs have a comparatively small air gap. Louis motor, long used in classrooms to illustrate motor principles, is extremely inefficient for the same reason, as well as appearing nothing like a modern motor. Electric motors revolutionized industry. Industrial processes were no longer limited by power transmission using line shafts, belts, compressed air or hydraulic pressure.

Instead, every machine could be equipped with its own power source, providing easy control at the point of use, and improving power transmission efficiency. Electric motors applied in agriculture eliminated human and animal muscle power from such tasks as handling grain or pumping water.

Household uses of electric motors reduced heavy labor in the home and made higher standards of convenience, comfort and safety possible. Today, electric motors consume more than half of the electric energy produced in the US.

The first alternating-current commutatorless induction motors were independently invented by Galileo Ferraris and Nikola Teslain andrespectively. Inthe Royal Academy of Science of Turin published Ferraris’s research detailing the foundations of motor operation, while concluding that “the apparatus based on that principle could not be of any commercial importance as motor.

One of the patents Tesla filed inhowever, also described a shorted-winding-rotor induction motor. George Westinghouse promptly bought Tesla’s patents, employed Tesla to develop them, and assigned C. Scott to help Tesla; however, Tesla left for other pursuits in Steadfast in his promotion of three-phase development, Mikhail Dolivo-Dobrovolsky invented the three-phase cage-rotor induction electrostandardds in and the three-limb transformer in This type of motor is now used for the vast majority of electrostandarvs applications.

Lamme later developed a rotating bar winding rotor. The General Electric Company began developing three-phase induction motors in In an electric motor, the moving part is the rotor, which turns the shaft to deliver the mechanical power. The rotor usually has conductors laid into it that carry currents, which interact with the magnetic field of the stator to generate the forces that turn the shaft.

Alternatively, some rotors carry permanent magnets, and the stator holds the conductors. The rotor is supported by bearingswhich allow the rotor to turn on its axis. The bearings are in turn supported by the motor housing. The motor shaft extends through the bearings to the outside of the motor, where the load is applied.

  ELECTROMECHANICAL DYNAMICS WOODSON PDF

Because the forces of the load are exerted beyond the electristandards bearing, elfctrostandards load is said to be overhung. The stator core is made up of many thin metal sheets, called laminations. Laminations are used to reduce energy losses that would result if a solid core were used. The distance between the rotor and stator is called the air gap. The air gap has electgostandards effects, and is generally as small as possible, as a large gap has a strong negative effect on performance.

It is the main source of the low power factor at which motors operate. The magnetizing current increases with the air gap. For this reason, the air gap electrostandadrs be minimal. Very small gaps may pose mechanical problems in addition to noise and losses.

Windings are wires that are laid in coilsusually wrapped around a laminated soft iron magnetic core so as to form magnetic poles when pphase with current. Electric machines come in two basic magnet field pole configurations: In the salient-pole machine the pole’s magnetic field is produced by a winding wound around the pole below the pole face. electrostamdards

Electro Standards Laboratories

In the nonsalient-pole electrostandarsd, or distributed field, or round-rotor, machine, the winding eoectrostandards distributed in pole face slots. Some motors have conductors that consist of thicker metal, such as bars or sheets of metal, usually copperalternatively aluminum. These are usually powered by electromagnetic induction. A commutator is a mechanism used to switch the input of most DC machines and certain AC machines. It consists of slip-ring segments insulated from each other and from the ohase.

The motor’s armature current is supplied through stationary brushes in contact with the revolving commutator, which causes required current reversal, and applies power to the machine in an optimal manner as the rotor rotates from pole to pole.

In light of improved technologies in the electronic-controller, sensorless-control, induction-motor, and permanent-magnet-motor fields, externally-commutated induction and permanent-magnet motors are electrostandafds electromechanically-commutated motors.

A DC motor is usually supplied through slip ring commutator as described above. AC motors’ commutation can be either slip ring commutator or externally commutated type, can be fixed-speed or variable-speed control type, and can be synchronous or asynchronous type. Universal motors can run on either AC or DC. Variable-speed controlled AC motors are provided with a range of different power invertervariable-frequency drive or electronic commutator technologies. The term electronic commutator is usually associated with self-commutated brushless DC motor and switched reluctance motor applications.

Electric motors operate on three different electrostamdards principles: By far, the most common is magnetism. In magnetic motors, magnetic fields are formed in both the rotor and the stator.

The product between these two fields gives rise to a force, and thus a torque on the motor shaft. One, or both, of these fields must be made to change with elecyrostandards rotation of the motor. This is done by switching the poles on and off at the right time, or varying the strength of the pole.

The main types are DC motors and AC motors, [59] the former increasingly being displaced by the latter. AC electric motors are either asynchronous or synchronous. Once started, a synchronous motor requires synchronism with the moving magnetic field’s synchronous speed for all normal torque conditions. In synchronous machines, the magnetic field must be provided by means other than induction such as from separately excited windings or permanent magnets.

A fractional-horsepower FHP motor either has a electrosandards below about 1 horsepower 0. Many household and industrial motors are in the fractional-horsepower class. By definition, all self-commutated DC motors run on DC electric power.

Most DC motors are small permanent dlectrostandards PM types.