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🚗 | Nissan X-Trail new model, "e-POWER" setting ... to be released in the European market in the summer of 2022

Photo Nissan X-Trail new model (Chinese specification)

Nissan X-Trail new model, "e-POWER" setting ... to be released in the European market in the summer of 2022

If you write the contents roughly
e-POWER is an electric powertrain that uses a gasoline engine only for power generation and is driven only by an electric motor.

Nissan Motor's European division will launch the new "X-TRAIL" (Nissan X-TRAIL) on April 4th in 19 ... → Continue reading


Wikipedia related words

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electric motor

electric motor(Dendoki,British: Electric motor) Means electrical energyMechanical energyConvert toPower equipment,Prime moverIs the general term for.motor,Electric motorAlso called[1].

In general,magnetic field(magnetic field)When電流Interaction (Lorentz force) Is used to output rotational motion, but linear motion is obtained.Linear motorAnd use ultrasonic vibration without using magnetic fieldUltrasonic motorEtc. have also been put into practical use.Electrostatic forceUsedElectrostatic motorHas been known for a long time.

Originally, the word "motor" ("moter") means "power" and is not particularly limited to electric motors.Therefore, a device that plays a role in some kind of power is often described as a motor (Rocket motorSuch).

In the following, we will mainly explain general electric motors that generate rotational force by electromagnetic force, and other than that.Linear motor,Ultrasonic motorWill be briefly explained at the end.

Today, electric motors account for more than half of electricity consumption.

Motor configuration

A rotating electric motor has a shaft and rotates.Rotor(Rotor: Rotor) and interacting with the rotorMoment of forceGeneratestator(Stator: Stator), rotation that transmits the rotation of the rotor to the outside, Support the axis of rotationbearingCaused by lossheatTo coolCooling deviceIt is composed of.

The part that generates the magnetic field of the rotor and statorFieldThat is.Electromagnets arranged so as to surround the rotor, ferromagnet iron cores that guide a magnetic field, and permanent magnets are used.

Commutator motor (Brush Motor)Synchronous motorSo, what generates a magnetic field to interact with the field and obtain torqueArmatureThat is.When an electric current flows through the electric wire, the Lorentz force acts due to the magnetic field of the field to rotate the rotor.

Coupling to connect with load equipment ・ Reduce the number of revolutions for the purposetorqueTo getDeceleratorEtc. are connected as an accessory device.

The commutator motor isCommutatorbrushBy switching the current flowing through the armature and maintaining the direction of rotation, continuous use is possible.

  • Rotor

A force is applied by the magnetic field of the stator and the current in the rotor to rotate the shaft.Some have permanent magnets in the rotor and conductors in the stator.A gap for rotation is required between the stator and the rotor.The gap width has a great influence on the electrical characteristics of the motor, and the motorPower factorIs the main cause of low.If the gap is large, the magnetization current increases and the power factor decreases. Therefore, it is better that the gap is narrow, but if it is too small, noise, loss, and mechanical problems may occur.

  • stator

The fixed part that surrounds the rotor in the electromagnetic circuit of the motor.It consists of an electromagnet with a wire wound around a ferromagnetic iron core and a field magnet, which is a permanent magnet.A magnetic field passes through the armature and creates a force on the winding.The stator core is configured by laminating a large number of thin metal plates that are insulated from each other, which is called lamination.The reason for stacking is to reduce the energy loss that occurs when a solid core is used.The "resin laminated motor" used in washing machines and air conditioners completely wraps the stator with resin, and uses the damping characteristics of the resin to reduce noise and vibration.

  • coil

A wire wound around a laminated soft iron magnetic core so as to form a magnetic pole when an electric current is passed through it.

In the series magnetic pole type, protrusions called magnetic poles face the ferromagnetic cores of the rotor and stator, and an electric wire is wound under the magnetic pole surface. It is supposed to be.On the other hand, in the non-parallel magnetic field type (distributed magnetic field type), the core of the ferromagnetic material has no magnetic poles, has a smooth cylindrical shape, and the windings are evenly arranged in a slot shape on the circumference.An alternating current flowing through the winding forms a magnetic pole in the core and rotates continuously. Kumatori magnetic pole type induction motorHas a winding on a part of the magnetic pole, which delays the phase of the magnetic field of the magnetic pole.

Inside the motor, a conductor made of thick metal such as rod-shaped or plate-shaped metal (usually copper or aluminum) is inserted and driven by electromagnetic induction.

  • Commutator

A rotary electric switch that supplies electric current to the rotor.A cylinder composed of a plurality of metal contacts is installed on the armature.Two or more soft, conductive "brushes" of electrical contacts, such as carbon, are pressed against the commutator and rotate while sliding into continuous segments of the commutator, supplying current to the rotor.The rotor windings are connected to the commutator segment.The commutator periodically reverses the direction of the current flowing through the windings of the rotor every half rotation (2 °) so that the torque applied to the rotor by the magnetic field of the stator is always in the same direction.Without this current reversal, the direction of the torque applied to each winding of the rotor would be reversed every half rotation, and the rotor would stop.Commutators are inefficient, and most motors with commutators have been replaced by brushless DC motors, permanent magnet motors, and induction motors.

Operating principle

There are various types of electric motors, but electric motors have a stator and a rotor, and one of them generates a magnetic field that changes in rotation, and the driving force is obtained by the change in the magnetic field.

Classification by rotor

Except for commutator motors, motors that have a coil in the stator and generate a fluctuating magnetic field by supplying a changing current to the coil can be classified into rotor types.

  1. permanent magnetField (Permanent Magnet Type): If the poles of a permanent magnet are arranged in the circumferential direction, a driving force is generated as the poles of the stator move.
  2. Electromagnet field: Since it is possible to give a magnetic field to the rotor with an electromagnet, both the rotor and the stator are configured to be electromagnets.
  3. Difference in magnetic permeability (Variable Reluctance Type): A driving force is generated by providing a protrusion on the magnetic material so that the magnetic field lines can easily pass through and difficult to pass through.
  4. Arago's disc : If a metal conductor is placed, an eddy current is generated by the change of the magnetic field, and a driving force is generated by the interaction with the magnetic field created by the eddy current.
  5. WindingShapeInduction motor : If a conductor coil is placed, a change in the magnetic field will generate a current that flows through the coil, and the interaction with the magnetic field will generate a driving force.

A plurality of coils on the driving side are provided in order to continuously generate a driving force in a certain direction, and the magnetic phases are shifted in order to generate the driving force.As for the method, various arrangements have been put into practical use.

またRotorstatorIt can be classified into inner rotor type, outer rotor type, and flat rotor type according to the internal and external positional relationship of.Linear motorIf you apply it toPrimary on-board type-Ground (orbit) linear expressionbecome.

Field and armature current types

Next, there are the following types of current for generating a magnetic field that fluctuates depending on the armature and the primary winding.

  1. Three-phase exchange : A rotating magnetic field can be generated by supplying a commercial three-phase alternating current (a sine wave out of phase by 120 degrees) to three or multiples of the coils.
  2. Single-phase AC: CapacitorIs often used to create another phase that is out of phase.
  3. Variable voltage variable frequency controlInverterThree-phase alternating current by: Commercial three-phase alternating current has a constant frequency, so it is used for starting and changing the speed.
  4. DCPulse: Feeds out-of-phase pulse voltages to separate coils.So-calledStepping motorCorresponds to this.
  5. Commutatorless motor (Brushless DC Motor)SensorThe rotor position is detected by the above, and the polarity of the direct current is switched accordingly.

The classification of DC motors and AC motors can be considered as the classification of usage, not the classification of the structure of the motor, and there may be motors that rotate in either case.

Classification of electric motors

Other classification

  • High-efficiency motor-Complies with high-efficiency motor standards.Less loss than ordinary motors.
  • - FieldTo exciteSuperconductivityElectric motor to use

Electric motor specifications

Motor loss

Motor loss is defined as the difference between input power and output work.

  • Total loss
    • Fixed loss
      • Iron loss : Hysteresis loss / eddy current loss
      •  : Friction loss / wind loss of bearing / cooling device
    • Load loss: Loss that occurs in proportion to load fluctuations

Special electric motor

Most electric motors generate changes in the magnetic field by electricity and generate rotational force by the changes in the magnetic field, but there are special electric motors with other principles and structures as described below.

Linear motor

Linear motorIs a rotary electric motorstatorOn the part that extends in a straight line corresponding toRotorA linear motion is obtained by changing the magnetic field by placing a part corresponding to.There are linear induction motors (LIM), linear synchronous motors (LSM), linear DC motors (LDM), linear stepping motors, linear piezoelectric motors, linear electrostatic motors, and the like.

Vibration motor

Ultrasonic vibration motor
Ultrasonic motorChanges small position changes due to deformation of the vibrating body into rotary motion or linear motion by friction.Lorentz forceLow efficiency compared to conventional motors that use
  • Piezoelectric elementThose that utilize the piezoelectric phenomenon caused by the above are sometimes called piezoelectric motors.It is used for focusing the camera.
Vibration motor
Has been developed for the purpose of vibrating incoming calls on mobile phones and the like.In some small ones, the center of gravity of the rotor is biased and the rotor itself is a weight that creates vibration.


Before the birth of the motor

In the 1740s, the first electric motors were simple electrostatic devices made by Scottish monk Andrew Gordon and American experimenter Benjamin Franklin.In front of modern electromagnetic motors, motors that are powered by static electricity (Electrostatic motor) Was being conducted.

1771 years,Henry CavendishDiscovered its theoretical principle but was not announced, in 1785CoulombDiscovered and announced independentlyCoulomb's lawIs called.An electrostatic motor has not been put into practical use because a high voltage is required to generate a force sufficient for practical use.

1799 years,Alessandro Volta Chemical batteryInvented, it became possible to produce a continuous electric current.

In 1820, Hans Christian Olstead discovered that an electric current created a magnetic field that exerted force on a magnet. Andre Marie AmpereDescribed the generation of mechanical forces due to electromagnetic interaction in just a few weeksAmpere's Lawannounced.

1821, British scientistMichael Faraday ElectromagneticAn experiment was conducted to convert electrical energy into kinetic energy by means of a target.Hang the lead wire from above,mercurySoak a little in the pool and put a permanent magnet on it.On that lead電流A round magnetic field is generated around the wire, and the wire rotates around the magnet.[3]..This experiment is often performed in school physics classes, but instead of toxic mercurybrineMay be used.this isHomopolar motorIt is the simplest type of electric motor called.Later improved this Barlow's Wheel There is also.These were for demonstration purposes and could not be used as a power source.

1827, HungarianJedrik AgnoshStarted experimenting with electromagnetically rotating devices, calling them "lightning-magnetic self-rotors".He uses it for college education, and in 1828 it was one of the three major elements of a practical DC motor.statorArmatureCommutatorWorld's first practical withDCI succeeded in experimenting with an electric motor.Both the fixed part and the rotating part are electromagnets, and no permanent magnets are used.[4][5][6][7][8][9]..This device was also for experimentation and could not be used as a power source.

DC motor

1832, British scientistWilliam sturgeonHowever, the world's first that can be used as a power source for machinesCommutatorInvented the type DC motor[10].

In 1837, he developed and patented a commutator-type DC motor for commercial use in the United States and with his wife Emily.This motor drove machines such as printing presses at a maximum speed of 600 rpm.[11]..As a power source at that timePower InputThere is no choice but for that electrodezincWas very expensive.As a result, the Davenports failed commercially and went bankrupt.There were several other inventors who developed DC motors, but all faced the problem of power supply costs.at that time,Power gridDid not exist yet.Therefore, there was no market for electric motors that was worth the power supply cost.[Source required].

1834, RussiaMoritz von JacobiHowever, he made the first full-scale rotary electric motor using a relatively weak rotary and reciprocating device.This motor had an amazing mechanical output.The motor set a world record, but set a new record for itself in 1838.The latter could be used to cross a wide river on a 14-seater boat. From 1839 to 40, other developers succeeded in making motors with similar or better performance.

In 1855, Jedrik created a device that did useful work on a similar principle to electromagnetic self-rotors.[4][6].. Also in the same year,Automobile driven by electric motorMaking a model of[12].

1864 years,Antonio PachinottiAnnounced the ring-shaped armature for the first time (initiallyDC generator(Invented as a dynamo).This is characterized by the fact that the coils are symmetrically arranged so as to be closed to each other, connected to the bar of the rectifier, and the brush supplies a constant current at a practically acceptable level. After the reinvention of Pachinotti's design in 1871 and the Zenove Gram, which adopted several solutions by Werner Siemens, DC motors finally became commercially successful.

1873 years,Zenobe GrammIs 2GeneratorI happened to discover that the power generated by one can be used to drive the other as an electric motor.This is the world's first commercially successful electric motor[Source required].

1872 years,Siemens und HalskeFriedrich von Hofner Altenneck of the company introduced a drum rotor instead of the Pakinotti ring armature to improve mechanical efficiency.The following year, the company introduced a laminate rotor to reduce iron loss and improve induced voltage. In 1880, Jonas Wenström added a slot in the rotor to accommodate the windings, further increasing efficiency.

1886 years,Frank SpragueInvented a spark-free DC motor that can maintain a constant rotational speed even when the load changes.Around this time, Sprague returns the power of the motor to the power grid.RegenerationInventing technologyTramWe also invented a method of collecting current from the overhead wire.Using these technologies, in 1887VirginiaRichmondSucceeded in operating a tram in 1892, an electric elevator and its control system, and moreIllinoisChicagoCentralized control type electric subway (commonly known asChicago L) Was successful.Taking advantage of Sprague's motors and related inventions, the demand for motors in the industry increased explosively, and other inventors invented similar systems one after another.

Improving the efficiency of electric motorsstatorRotorIt was hard to realize that it was important to reduce the gap between the two, and progress was delayed for decades.In early motors, the gap was relatively large, and the magnetic circuitMagnetic resistanceWas very large.For this reason, the torque that can be generated with the same power consumption is considerably smaller than that of modern efficient electric motors.The reason for this is thought to be that the closer the magnets and electromagnets are, the stronger the attractive force is, so we tried to separate them to some extent.In an efficient design, the gap between the stator and the rotor should be as small as possible to create a magnetic flux pattern that easily generates torque.

AC motor

1824, French physicistFrancois AragoBut"Arago's discThe rotating magnetic field known as "" was formulated. Primitive by Walter Bailey manually switching on and off in 1879Induction motorWas produced. In the 1880s, although the advantages of alternating current in long-distance high-voltage power transmission were recognized, the challenge was to operate the motor with alternating current, so practical AC motors were actively developed.

1885 years,Galileo FerrarisBy the first AC commutatorlessInduction motorWas invented. In 1888, the Royal Academy of Sciences of Turin published a study of Ferraris detailing the basics of motor operation, but at that time it was concluded that "devices based on that principle cannot have commercial significance as motors". It was.

1887 years,Nikola TeslaIs the first practicalAC motorInvented and obtained a patent in 1888.That same year, Tesla published a treatise, "A New System for Alternating Current Motors and Transformers," in AIEE, explaining three types of patented two-phase, four-pole motors. Non-self-starting with 3-pole rotorReluctance motorA self-starting induction motor with a winding rotor, a true synchronous motor that supplies individually excited DC power to the rotor windings.The patent also described an induction motor for a short-circuit wound rotor.George Westinghouse, who had already acquired rights from Ferraris, immediately bought a Tesla patent.Constant-speed AC induction motors were not suitable for trams, but Westinghouse adopted them in 1891 to power its mining business in Telluride, Colorado.The company realized the first practical induction motors in 1892 and developed a line of multi-phase 1893-hertz induction motors in 60, but these early Westinghouse motors were two-phase motors with winding rotors. It was.Later, BG Ramme developed a rotary rod winding rotor.

In 1889, Mikhail Dolivo-Duvrovorsky with a starting rheostat with both a cage rotor and a winding rotor.Three-phase induction motorIn 1890, he invented a three-limb transformer and steadily proceeded with three-phase development. AEGAnd Maschinenfabrik OerlikonMikhail Dolivo-DobrovolskyAnd Charles Eugene Lancelot Brown have developed a large 20-horsepower squirrel-cage model and a 100-horsepower winding model with a starting rheostat. After 1889, Wenstrom began developing a similar three-phase machine. At the 1891 Frankfurt International Electrical Technology Expo, he successfully unveiled his first long-range three-phase system.It was rated at 15 kV and extended 175 km from Laufen Falls on the Neckar River.Laufen's power plant has a 240kW 86V 40Hz AC generator and a step-up transformer. At the exhibition, a step-down transformer supplies power to a 100-horsepower three-phase induction motor to move an artificial waterfall, expressing the movement of the original power supply. did.Three-phase induction is currently used in most commercial motors.Dolivovolsky argued that Tesla's motors were impractical due to their two-phase pulsation, which prompted him to stick to his three-phase study.

1891 years,General ElectricThe company has started the development of a three-phase induction motor. In 1896, General Electric and Westinghouse signed a cross-licensing agreement for the design of a bar winding rotor, later called the Riskage Rotor.Due to these inventions and technological innovations that have led to improvements in induction motors, 100-hp induction motors are now the same size as the 1897 7.5-hp motors.

Electric motor in Japan

1895 (Meiji 28), Shibaura Seisakusho (currentToshiba) Created Japan's first two-phase induction motor with 6 poles and 25 horsepower (18.5 kW) for copper mine pumps.

1901 (Meiji 34),MeidenshaManufactured a one-horsepower (1kW) three-phase induction motor.

1906 (Meiji 39),MeidenshaHas standardized a three-phase induction motor with 5 horsepower (3.8 kW) or less using its own design method, and started full-scale production as a general-purpose motor.

In 1906 (Meiji 39), a survey as of the end of December,MeidenshaOccupied about 6% of the electric motor Shure in Tokyo.Of the 746 electric motors in Tokyo, 463 were made by Meidensha, and the majority of the remaining 283 were imported products.[13]

A short film about electric motors

Matsushita Electric Industrial Co., Ltd. (currently one of the electric motor manufacturers)Panasonic), In 1963,Power Technology-Motor-A short film (about 28 minutes) entitled "" has been produced.

In this movie work, starting from the explanation of the principle of the motor, the scene of the assembly site of each of the various motor products and the operation scene of the finished product are explained.Tatsuya Jô OfNarrationEntered and introduced.

Here, "Motor" seen in the movie title is a notation based on the German pronunciation of "Motor", which was modeled until the first half of the 20th century. The notation "motor" is not used (production of motors for general industry continues) >>[1].

This movie work was produced by Tokyo Cinema (currently Tokyo Cinema Shinsha) and is currentlyScience picture museum(NPO corporation, association supporting science picture museum) It is released for free on the website.


  1. ^ a b Regarding the katakana notation "motor"Institute of Electrical EngineersIn "motorIn addition to the notation of "motor" depending on the electric motor manufacturerGermanThe notation "Motor" was used as a model for German pronunciation until the first half of the 20th century.Stage pronunciationFollowing the pronunciation based on ""Motor"(Or"Motor") Can be seen using the notation <<NidecIn the website "What is a motor? 1-3-6.Ultrasonic motorFrom the column "Etymology of Motors" published in the latter half of the page; the notation "motor" is currently at least日立Of seriesHitachi Industrial Equipment SystemToshibaMainly used in brand names in affiliated Toshiba Industrial Equipment Systems >>
  2. ^ Faraday, Michael (1844). Experimental Researches in Electricity. 2  See plate 4.
  3. ^ spark museum
  4. ^ a b Electricity and magnetism, translated from the French of Amédée Guillemin. Rev. and ed. By Silvanus P. Thompson. London, MacMillan, 1891
  5. ^ Nature 53. (printed in 1896) page: 516
  6. ^ a b Battery and Technology History Timeline Electropedia
  7. ^ http://www.fh-zwickau.de/mbk/kfz_ee/praesentationen/Elma-Gndl-Generator%20-%20Druckversion.pdf
  8. ^ http://www.uni-regensburg.de/Fakultaeten/phil_Fak_I/Philosophie/Wissenschaftsgeschichte/Termine/E-Maschinen-Lexikon/Chronologie.htm
  9. ^ Electrical Technology History Electropedia
  10. ^ Gee, William (2004). “Sturgeon, William (1783–1850)”. Oxford Dictionary of National BiographyOxford, England: Oxford University Press. two:10.1093 / ref: odnb / 26748 
  11. ^ Garrison, Ervan G., "A history of engineering and technology".CRC Press, 1998. ISBN 084939810X, 9780849398100. Retrieved May 7, 2009.
  12. ^ http://www.frankfurt.matav.hu/angol/magytud.htm
  13. ^ "Friend of Electricity" (1906) |


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