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Reduced Voltage Starter Configurations
Reduced Voltage Starter Configurations

G1XXVN - Zeftronics
G1XXVN - Zeftronics

DOE Fundamentals Handbook Electrical Science Volume 4 of 4
DOE Fundamentals Handbook Electrical Science Volume 4 of 4

Circuit breakers
Circuit breakers

... the insulating nozzle 76. The spinning also enhances interrup ...
50 performance analysis of pid controller for three- phase
50 performance analysis of pid controller for three- phase

... the three-phase inverter. The six number of IGBTs in the three-phase inverter are all of same rating and they are two complementary switch pairs in each phase in which only one of the switches in a pair will turn on each time while the other will be turned off. The PWM switching technique generates ...
Basic Concepts - New Age International
Basic Concepts - New Age International

... It is seen from Blv and BlI equations that generator and motor actions are based on the physical reactions on conductors situated in magnetic fields. When a relative motion between conductor and field exists, an emf is generated in the conductor and when a conductor carries current and is situated i ...
Understanding Motor Nameplate Information NEMA
Understanding Motor Nameplate Information NEMA

... against intermittent heat rises, and helps to offset low or unbalanced line voltages. For example, the standard SF for open drip-proof (ODP) motors is 1.15. This means that a 10-hp motor with a 1.15 SF could provide 11.5 hp when required for short-term use. Some fractional horsepower motors have hig ...
SUMMARY OF TOPICS
SUMMARY OF TOPICS

... intended to result in Standards and requirements that are more reflective of current and emerging technologies such as brushless DC (BLDC) or electrically commutated motors (ECM), servo motors, stepper motors, and the like. In addition, this is intended to result in Standards that represent the most ...
CONTENTS - Hodder Education
CONTENTS - Hodder Education

... Figure 12.22a) we would get the same effect as moving the magnet to the right by moving the coil to the left. The important idea is that there must be relative movement between the magnet and the coil. When a current is produced by electromagnetic induction, energy is always needed to create the ele ...
III Sem
III Sem

TEMP EFFECTS full paper Jan3.indd
TEMP EFFECTS full paper Jan3.indd

... (KE) are directly related to the magnetic flux density (Br) of the permanent magnets. Depending on the physics of the magnet material used, overall flux density will change at a given percentage with an increase in magnet temperature. As the material temperature increases, atomic vibrations cause on ...
- aes journals
- aes journals

... predominate Conventional PWM power converters when operated in a switched mode operation, the Power Switches have to cut off the load current within the turn-on and turn-off times under the hard switching conditions. Hard switching refers to the stressful switching behavior of the power electronic d ...
06310013, 06210001, 05310059, 06310041
06310013, 06210001, 05310059, 06310041

Motor Single-Phasing Voltage Unbalance
Motor Single-Phasing Voltage Unbalance

EASA Standard AR100-1010 - Electrical Apparatus Service
EASA Standard AR100-1010 - Electrical Apparatus Service

Simulation and Testing of a Switched Reluctance Motor By Matlab
Simulation and Testing of a Switched Reluctance Motor By Matlab

... electrical machines due to its construction, where only stator windings and a magnetic rotor in a saliency form are used. In the late 70, popularity of concepts of these type machines was fostered with the assistance of fast development switching technologies [8]. Even though the construction is sim ...
What Do All Those Things on an AC Motor Nameplate Mean?
What Do All Those Things on an AC Motor Nameplate Mean?

... motor would run if it were fixed to the ac power line frequency; that is, if it turned at the same speed as the rotating magnetic field created by the combination of winding pattern and power line frequency. An induction motor's speed is always less than synchronous speed and it drops off as load in ...
EE 1281721
EE 1281721

Motors and Generators - Instructor Guide
Motors and Generators - Instructor Guide

... 1. A load can be connected to armature without having moving contacts (slip rings and brushes) in circuit 2. Much easier to insulate stator conductors than rotating conductors 3. Much higher output voltages and currents can be generated ...
ABB drives - Technical guide No. 5 - Bearing currents in modern AC
ABB drives - Technical guide No. 5 - Bearing currents in modern AC

... over the bearing. In the case of high frequency bearing currents, this voltage can be generated in three different ways. The most important factors that define which mechanism is prominent, are the size of the motor and how the motor frame and shaft are grounded. The electrical installation, meaning ...
Axial Flux Permanent Magnet Generator Design for
Axial Flux Permanent Magnet Generator Design for

... used applications, are direct battery charing and grid connection. The small wind turbine construction procedure is the same in both direct battery charing and grid connection schemes, but some different design requirements need to be considered. Direct battery charging applications [5], are usually ...
AN2446
AN2446

alternators
alternators

High-Temperature Cuprate Superconductors Get to Work
High-Temperature Cuprate Superconductors Get to Work

... HTS motors, and of superconducting quantum interfer- High-temperature cuprate superconductors are among the ence devices (SQUIDs) that could detect minute magnetic most complex materials ever explored for practical applifields and contribute to medical research and other fields. cation.3 The need to ...
EASA`s "Getting the most from your Electric Motors"
EASA`s "Getting the most from your Electric Motors"

... an adjustable-speed drive (ASD) or variable-frequency drive (VFD) application, use an “inverter-duty” motor (or provide suitable filtering) and keep the supply cable length within the motor manufacturer’s guidelines. Use supply conductors designed for ASD circuits to reduce the risk of overvoltages ...
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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.
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