section 15170-motors - DeCA Facilities Website
... Explosion-Proof Motors: UL approved and labeled for hazard classification, with over temperature protection. ...
... Explosion-Proof Motors: UL approved and labeled for hazard classification, with over temperature protection. ...
Utilization of Repetitive Surge Oscillograph (RSO) in the Detection of
... chosen by the various RSO manufactures in such a manner that the equipment is sensitive to shorted-turns for all large rotors. ...
... chosen by the various RSO manufactures in such a manner that the equipment is sensitive to shorted-turns for all large rotors. ...
CHAPTER 11
... The commutator consists of a number of copper segments that are electrically insulated from each other and from the rotor shaft. The brushes are held by springs against the rotating of the commutator so as to make electrical contact and to provide a connection from the rotating coils to the outside ...
... The commutator consists of a number of copper segments that are electrically insulated from each other and from the rotor shaft. The brushes are held by springs against the rotating of the commutator so as to make electrical contact and to provide a connection from the rotating coils to the outside ...
halaman pengesahan - (COT) Publications
... The stator and rotor winding of DFIG can be assumed as two balanced three-phase windings coupled with each other. In which, Clark transformation may be applied for simplification by reducing a coupled balanced of three-phase winding into an uncoupled two-phase winding. By doing so, the machine equat ...
... The stator and rotor winding of DFIG can be assumed as two balanced three-phase windings coupled with each other. In which, Clark transformation may be applied for simplification by reducing a coupled balanced of three-phase winding into an uncoupled two-phase winding. By doing so, the machine equat ...
Upgrading the Rotor Ground Fault Protection on Electric Generators
... the field voltage and the fault location. With low side injection, a fault near the negative side of the winding will typically need to be an order of magnitude lower in resistance before detection occurs, than a fault near the higher DC voltage at the positive winding terminal. The ground fault det ...
... the field voltage and the fault location. With low side injection, a fault near the negative side of the winding will typically need to be an order of magnitude lower in resistance before detection occurs, than a fault near the higher DC voltage at the positive winding terminal. The ground fault det ...
A TORQUE TRACKING CONTROL ALGORITHM FOR DOUBLY
... A doubly-fed induction generator is an electrical asynchronous three-phase machine with open rotor windings which can be fed by external voltages. The typical connection scheme of this generator is reported in Fig. 1. The stator windings are directly connected to the line grid, while the rotor windi ...
... A doubly-fed induction generator is an electrical asynchronous three-phase machine with open rotor windings which can be fed by external voltages. The typical connection scheme of this generator is reported in Fig. 1. The stator windings are directly connected to the line grid, while the rotor windi ...
DC Motors.pdf - 123seminarsonly.com
... forces, and because the windings are supported by the housing, they can be cooled by conduction, requiring no airflow inside the motor for cooling. This in turn means that the motor's internals can be entirely enclosed and protected from dirt or other foreign matter. The maximum power that can be ap ...
... forces, and because the windings are supported by the housing, they can be cooled by conduction, requiring no airflow inside the motor for cooling. This in turn means that the motor's internals can be entirely enclosed and protected from dirt or other foreign matter. The maximum power that can be ap ...
Experiment 7 - WFU Physics
... The electric field generated by the changing magnetic field can be detected by the electric force which charged bodies in the region experience. If there is a conductor which is part of a closed circuit in the region, it is possible that the induced electric field will drive negative charges along t ...
... The electric field generated by the changing magnetic field can be detected by the electric force which charged bodies in the region experience. If there is a conductor which is part of a closed circuit in the region, it is possible that the induced electric field will drive negative charges along t ...
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.