• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Motors - MD Anderson Cancer Center
Motors - MD Anderson Cancer Center

... 2. All motor bearings shall be factory prepacked with a nondetergent lubricant and shall be provided with lubrication fitting arranged to provide easy access when installed on the driven apparatus except as noted hereinafter. 3. Permanently lubricated factory-sealed motors may be provided in fractio ...
Conventional DC Machines and Universal Motor - Lab-Volt
Conventional DC Machines and Universal Motor - Lab-Volt

... The purchaser shall receive a single right of use which is non-exclusive, non-time-limited and limited geographically to use at the purchaser's site/location as follows. The purchaser shall be entitled to use the work to train his/her staff at the purchaser's site/location and shall also be entitled ...
MJB 250-315-355
MJB 250-315-355

IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) ISSN: 2278-1676
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE) ISSN: 2278-1676

Full Text
Full Text

Asynchronous performance analysis of a single
Asynchronous performance analysis of a single

How To Specify A Slip Ring
How To Specify A Slip Ring

... 1. Slip Ring Capsule - A fully integrated A slip ring must be mounted with a flexible u n i t w i t h a h o u s i n g a n d b e a r i n g s . coupling on one side of the unit. Hard 2. Slip Ring Separates - Separate slip ring rotor mounting on both the rotor and stator will and brush blocks for mount ...
Design of Direct Torque Controller of Induction Motor (DTC)
Design of Direct Torque Controller of Induction Motor (DTC)

... In order to design a mathematical model for IM, the following assumptions should be valid. 1- The stator and rotor windings are represented by stator and rotor resistances ( , ) respectively. 2- The flux in the stator and rotor are represented by stator and rotor inductances ( , ) respectively. 3- ...
International Electrical Engineering Journal (IEEJ) Vol. 5 (2014) No.12, pp. 1680-1687
International Electrical Engineering Journal (IEEJ) Vol. 5 (2014) No.12, pp. 1680-1687

Cast Coil Transformers
Cast Coil Transformers

... The low voltage coils are made with copper or aluminum foil with a thermal insulation system designed per operating conditions F, H, or C. The coils are pre-impregnated with epoxy resin, an excellent adhesive, which provides an optimum coil insulation and high mechanical strength. Winding leads are ...
lecture notes on electrical technology –r15
lecture notes on electrical technology –r15

... rectangular coils and are then pulled into their proper shape in a coil puller. Various conductors of the coils are insulated from each other. The conductors are placed in the armature slots, which are lined with tough insulating material. This slot insulation is folded over above the armature condu ...
Fast Switching Direct Torque Control Using a Single DC-link
Fast Switching Direct Torque Control Using a Single DC-link

... This paper presents a fast switching direct torque control (FS-DTC) using only a single DC-link current sensor. In FS-DTC, six new active voltage complex space vectors (CSVs) are synthesized by the conventional active voltage space vectors (SVs). The corresponding sectors are rotated in the anticloc ...
Solenoid Rebuilding - Vensel Enterprises
Solenoid Rebuilding - Vensel Enterprises

Speed-Sensorless AC Drives With the Rotor Time Constant
Speed-Sensorless AC Drives With the Rotor Time Constant

... exploit the anisotropic properties of machine. The introduction of test signal keeps machine observable even when rotorinduced voltage approaches zero. Uses of different machine anisotropies are reported, such as magnetic saturation or rotor slotting [2] or rotor slot openings modified in sinusoidal ...
Permanent Magnet Synchronous Motors (PMSM). Parameters
Permanent Magnet Synchronous Motors (PMSM). Parameters

... Permanent magnet synchronous motors are increasing applied in several areas such as traction, automobiles, robotics and aerospace technology. The power density of permanent magnet synchronous motor is higher than one of induction motor with the same ratings due to the no stator power dedicated to th ...
Field Weakening of Permanent Magnet Machines
Field Weakening of Permanent Magnet Machines

... machines has grown tremendously during the last decade. Meanwhile, a great progress has been achieved not only in the development of permanent magnets but in the area of electric machine design and power electronics as well. Therefore, PM machines have been drawing more and more attention. Developme ...
Energy $aver VHS Guideform Specification ()
Energy $aver VHS Guideform Specification ()

Understanding Generator Ripple Waveforms
Understanding Generator Ripple Waveforms

... greater than what the 50 amp current probe can measure. This will result in the oscilloscope trace either flat-lining the tops of some ripple pulses or the oscilloscope trace dropping to 0. An example illustration of this is provided later in the document. Switch to the 500 amp probe when testing th ...
UNIT 5 INDUCTION MOTOR
UNIT 5 INDUCTION MOTOR

... The shaft of an induction motor is short and stiff, in order to keep as small an airgap as is mechanically possible. This helps in removing any significant deflection in the rotor. Even a small deflection in the shaft, and hence rotor, would create large irregularities in the air-gap length which wo ...
Microelectromechanical Devices
Microelectromechanical Devices

... ECE 8830 - Electric Drives ...
Auto transformer
Auto transformer

... • As only one winding is uses the copper required for the transformer is very less • The size and hence the cost is reduced as ccompared to the conventional transformer • The losses taking place in the winding are reduced the efficiency is higher then the conventional transformer • Due to reduced r ...
Trade of Motor Mechanic Module 2
Trade of Motor Mechanic Module 2

Slide 1
Slide 1

External Characteristic of Separately Excited DC Generator
External Characteristic of Separately Excited DC Generator

... terminal voltage of the machine increases. But after reaching its maximum value it starts to decrease due to excessive demagnetizing effect of armature reaction. This phenomenon is shown in the figure by the dotted line.  Dotted portion of the characteristic gives approximately constant electric cu ...
Motor Trouble-Shooting Chart
Motor Trouble-Shooting Chart

< 1 ... 11 12 13 14 15 16 17 18 19 ... 83 >

Commutator (electric)



A commutator is the moving part of a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. It consists of a cylinder composed of multiple metal contact segments on the rotating armature of the machine. The commutator is one component of a motor; there are also two or more stationary electrical contacts called ""brushes"" made of a soft conductor like carbon press against the commutator, making sliding contact with successive segments of the commutator as it rotates. The windings (coils of wire) on the armature are connected to the commutator segments. Commutators are used in direct current (DC) machines: dynamos (DC generators) and many DC motors as well as universal motors. In a motor the commutator applies electric current to the windings. By reversing the current direction in the rotating windings each half turn, a steady rotating force (torque) is produced. In a generator the commutator picks off the current generated in the windings, reversing the direction of the current with each half turn, serving as a mechanical rectifier to convert the alternating current from the windings to unidirectional direct current in the external load circuit. The first direct current commutator-type machine, the dynamo, was built by Hippolyte Pixii in 1832, based on a suggestion by André-Marie Ampère. Commutators are relatively inefficient, and also require periodic maintenance such as brush replacement. Therefore, commutated machines are declining in use, being replaced by alternating current (AC) machines, and in recent years by brushless DC motors which use semiconductor switches.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report