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Permanent-magnet Electric Motor
A brushed DC electric motor is an internally commutated electric motor designed to be run from a direct current power source and utilizing an electric brush for contact. Brushed motors were the first commercially important application of electric power to driving mechanical energy, and DC distribution systems were used for more than 100 years to operate motors in commercial and industrial buildings. Brushed DC motors can be varied in speed by changing the operating voltage or the strength of the magnetic field. Depending on the connections of the field to the power supply, the speed and torque characteristics of a brushed motor can be altered to provide steady speed or speed inversely proportional to the mechanical load. Brushed motors continue to be used for electrical propulsion, cranes, paper machines and steel rolling mills. Since the brushes wear down and require replacement, brushless DC motors using power electronic devices have displaced brushed motors from many applicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commutator (electric)
A commutator is 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. Two or more electrical contacts called " brushes" made of a soft conductive material 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamo - Commutating Plane Definitions
"Dynamo Electric Machine" (end view, partly section, ) A dynamo is an electrical generator that creates direct current using a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundation upon which many other later electric-power conversion devices were based, including the electric motor, the alternating-current alternator, and the rotary converter. Today, the simpler alternator dominates large scale power generation, for efficiency, reliability and cost reasons. A dynamo has the disadvantages of a mechanical commutator. Also, converting alternating to direct current using rectifiers (such as vacuum tubes or more recently via solid state technology) is effective and usually economical. History Induction with permanent magnets The Faraday disk was the first electric generator. The horseshoe-shaped magnet ''(A)'' created a magnetic field through the disk ''(D)''. When the disk was turned, this induced an electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Series Wound Motor
Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used in serialism including tone rows * Harmonic series (music) * Serialism, including the twelve-tone technique Types of series in arts, entertainment, and media * Anime series * Book series * Comic book series * Film series * Manga series * Podcast series * Radio series * Television series * "Television series", the Australian, British, and a number of others countries' equivalent term for the North American "television season", a set of episodes produced by a television serial * Video game series * Web series Mathematics and science * Series (botany), a taxonomic rank between genus and species * Series (mathematics), the sum of a sequence of terms * Series (stratigraphy), a stratigraphic unit deposited during a certain interval of geologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shunt (electrical)
In electronics, a shunt is a device that creates a low- resistance path for electric current, to allow it to pass around another point in the circuit.Rudolf F. Graf, ''Modern dictionary of Electronics'', Mc-Graw Hill, 1968 Library of Congress 68-13873 ''Shunt'' page 454. The origin of the term is in the verb 'to shunt' meaning to turn away or follow a different path. Defective device bypass One example is in miniature Christmas lights which are wired in series. When the filament burns out in one of the incandescent light bulbs, the full line voltage appears across the burnt out bulb. A shunt resistor, which has been connected in parallel across the filament before it burnt out, will then short out to bypass the burnt filament and allow the rest of the string to light. If too many lights burn out however, a shunt will also burn out, requiring the use of a multimeter to find the point of failure. Photovoltaics In photovoltaics, the term is widely used to describe an ''unwan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Series And Parallel Circuits
Two-terminal components and electrical networks can be connected in series or parallel. The resulting electrical network will have two terminals, and itself can participate in a series or parallel topology. Whether a two-terminal "object" is an electrical component (e.g. a resistor) or an electrical network (e.g. resistors in series) is a matter of perspective. This article will use "component" to refer to a two-terminal "object" that participate in the series/parallel networks. Components connected in series are connected along a single "electrical path", and each component has the same current through it, equal to the current through the network. The voltage across the network is equal to the sum of the voltages across each component. Components connected in parallel are connected along multiple paths, and each component has the same voltage across it, equal to the voltage across the network. The current through the network is equal to the sum of the currents through each com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armature Controlled DC Motor
An armature controlled DC motor is a direct current (DC) motor that uses a permanent magnet driven by the armature coils only. Basic operation of DC motor A motor is an actuator, converting electrical energy in to rotational mechanical energy. A motor requiring a DC power supply for operation is termed a DC motor. DC motors are widely used in control applications like robotics, tape drives, machines and many more. Separately excited DC motors are suitable for control applications because of separate field and armature circuit. Two ways to control DC separately excited motors are: Armature Control and Field Control. A DC motor consists of two parts: a rotor and a stator. The stator consists of field windings while the rotor (also called the armature) consists of an armature winding. When both the armature and the field windings are excited by a DC supply, current flows through the windings and a magnetic flux proportional to the current is produced. When the flux from the fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serie Shunt Coumpound
Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used in serialism including tone rows * Harmonic series (music) * Serialism, including the twelve-tone technique Types of series in arts, entertainment, and media * Anime series * Book series * Comic book series * Film series * Manga series * Podcast series * Radio series * Television series * "Television series", the Australian, British, and a number of others countries' equivalent term for the North American "television season", a set of episodes produced by a television serial * Video game series * Web series Mathematics and science * Series (botany), a taxonomic rank between genus and species * Series (mathematics), the sum of a sequence of terms * Series (stratigraphy), a stratigraphic unit deposited during a certain interval of geologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compensation Winding
A compensation winding in a DC shunt motor is a winding in the field pole face plate that carries armature current to reduce stator field distortion. Its purpose is to reduce brush arcing and erosion in DC motors that are operated with weak fields, variable heavy loads or reversing operation such as steel-mill motors. When flux from the armature current is about equal to the flux from the field current, the flux at the field pole plate is shifted. Under a fixed load, there is an optimal commutation point for the brushes that minimizes arcing and erosion of the brushes. When the ratio of armature flux to field flux varies greatly or reverses, the optimum commutation point shifts as result of the varying flux at the pole face plate. The result is arcing of the brushes. By adding a compensating winding in the pole face plate that carries armature current in the opposite direction of current in the adjacent armature windings, the position of the flux at the pole face plate can b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawkins Electrical Guide
The ''Hawkins Electrical Guide'' was a technical engineering book written by Nehemiah Hawkins, first published in 1914, intended to explain the highly complex principles of the new technology of electricity in a way that could be understood by the common man. The book is notable for the extremely high number of detailed illustrations it contains, and the small softbound size of the volumes. The book was published by Theodore Audel & Company, and the majority of the illustrative content became the basis of decades of follow-up books published under the ''Audels'' brand name. The illustrative content of these books can still be found in Audels books sold new today. Because the ''Hawkins Electrical Guide'' was printed in the United States prior to 1923, the content of the books has passed into the public domain. Free media access on the Internet Due to several book digitizing initiatives such as the Gutenberg project, and , many of these older public domain books are becomin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamo - Commutating Plane Field Distortion
"Dynamo Electric Machine" (end view, partly section, ) A dynamo is an electrical generator that creates direct current using a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundation upon which many other later electric-power conversion devices were based, including the electric motor, the alternating-current alternator, and the rotary converter. Today, the simpler alternator dominates large scale power generation, for efficiency, reliability and cost reasons. A dynamo has the disadvantages of a mechanical commutator. Also, converting alternating to direct current using rectifiers (such as vacuum tubes or more recently via solid state technology) is effective and usually economical. History Induction with permanent magnets The Faraday disk was the first electric generator. The horseshoe-shaped magnet ''(A)'' created a magnetic field through the disk ''(D)''. When the disk was turned, this induced an electr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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