EEEB283 Electrical Machines & Drives
... For below base speed operation: Frequency reduced at rated Vs - airgap flux saturates (f ,ag and enters saturation region oh B-H curve): - excessive stator currents flow - distortion of flux wave - increase in core losses and stator copper loss Hence, keep ag = rated flux stator voltag ...
... For below base speed operation: Frequency reduced at rated Vs - airgap flux saturates (f ,ag and enters saturation region oh B-H curve): - excessive stator currents flow - distortion of flux wave - increase in core losses and stator copper loss Hence, keep ag = rated flux stator voltag ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
... processes, accounting for more than two-thirds of industrial electricity consumption. Classifying on the basis of motors usually used, about 90% are three-phase ac induction based, mainly due to low cost, mechanical robustness and balancing of current over 3 phases.Torque is the main parameters in p ...
... processes, accounting for more than two-thirds of industrial electricity consumption. Classifying on the basis of motors usually used, about 90% are three-phase ac induction based, mainly due to low cost, mechanical robustness and balancing of current over 3 phases.Torque is the main parameters in p ...
Electrical Machines - Questions and Answers
... The bimetallic thermal relay consists of a small bimetallic strip that is heated by an element connected in series with the supply. When the current rises above a preset value, the movement of the strip releases a catch which opens the trip contacts. In recent years more modern electronic relays are ...
... The bimetallic thermal relay consists of a small bimetallic strip that is heated by an element connected in series with the supply. When the current rises above a preset value, the movement of the strip releases a catch which opens the trip contacts. In recent years more modern electronic relays are ...
Power Flow Control of a Doubly Fed induction Generator (DFIG)
... and reactive power is synthesized using PI controllers. Their respective performances are in terms of stator currents references tracking. ...
... and reactive power is synthesized using PI controllers. Their respective performances are in terms of stator currents references tracking. ...
Design and Simulation of Solar Powered B-4
... ABSTRACT In this paper solar powered B-4 inverter for induction motor is presented. The speed of an induction motor is controlled by three phase inverter normally have six switches. Instead of using six switches the performance of induction motor is realized by four switch three phase inverter (FSTP ...
... ABSTRACT In this paper solar powered B-4 inverter for induction motor is presented. The speed of an induction motor is controlled by three phase inverter normally have six switches. Instead of using six switches the performance of induction motor is realized by four switch three phase inverter (FSTP ...
phase advancers
... 3 phase supply at line frequency fed to the exciter will set up a rotating magnetic field at speed NS relative to armature of exciter. The arrangement is such that the rotation of the exciter and its field are in opposite direction. The speed of the field relative to fixed brushes will now be the ...
... 3 phase supply at line frequency fed to the exciter will set up a rotating magnetic field at speed NS relative to armature of exciter. The arrangement is such that the rotation of the exciter and its field are in opposite direction. The speed of the field relative to fixed brushes will now be the ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
... The power source is presented in the source block with voltage U supplying the transistorised inverter simulation block. The order of commutation of phases is defined depending on the rotor’s angle of rotation by the rotor position block, which, by imitating the operation of the position captor, gen ...
... The power source is presented in the source block with voltage U supplying the transistorised inverter simulation block. The order of commutation of phases is defined depending on the rotor’s angle of rotation by the rotor position block, which, by imitating the operation of the position captor, gen ...
IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
... both the rotor and stator. As a result of its inherent simplicity, the SRM promises a reliable and a low-cost variable-speed drive and will undoubtedly take the place of many drives now using the cage induction, PM and DC machines in the short future. The number of poles on the SRM’s stator is usual ...
... both the rotor and stator. As a result of its inherent simplicity, the SRM promises a reliable and a low-cost variable-speed drive and will undoubtedly take the place of many drives now using the cage induction, PM and DC machines in the short future. The number of poles on the SRM’s stator is usual ...
Experience with On line PD Measurements on By James Cowling Martec
... • 80pF Capacitive Couplers (vendor neutral) • Stator Winding RTD’s • RFCT’s ...
... • 80pF Capacitive Couplers (vendor neutral) • Stator Winding RTD’s • RFCT’s ...
Major I
... resistance of 0.015 Ω and a leakage reactance of 0.024Ω. the core loss is 175 W. Find the following: (a) Equivalent impedances referred to the high-voltage winding. (b) Voltage regulation for full load at 230 V and 0.866 power factor lagging (c) The efficiency of the transformed under the condition ...
... resistance of 0.015 Ω and a leakage reactance of 0.024Ω. the core loss is 175 W. Find the following: (a) Equivalent impedances referred to the high-voltage winding. (b) Voltage regulation for full load at 230 V and 0.866 power factor lagging (c) The efficiency of the transformed under the condition ...
Document
... 2.) To calculate the actual motor speed what has to be included in the above formula? slip (120 x f / P) - slip 3.) The majority of electric motors used in general purpose applications in industry today are what NEMA design? NEMA design B 4.) A NEMA design D motor is characterized by very high break ...
... 2.) To calculate the actual motor speed what has to be included in the above formula? slip (120 x f / P) - slip 3.) The majority of electric motors used in general purpose applications in industry today are what NEMA design? NEMA design B 4.) A NEMA design D motor is characterized by very high break ...
Lecture Notes EEE 360
... • The direct current (dc) machine can be used as a motor or as a generator. • DC Machine is most often used for a motor. • The major advantages of dc machines are the easy speed and torque regulation. • However, their application is limited to mills, mines and trains. As examples, trolleys and under ...
... • The direct current (dc) machine can be used as a motor or as a generator. • DC Machine is most often used for a motor. • The major advantages of dc machines are the easy speed and torque regulation. • However, their application is limited to mills, mines and trains. As examples, trolleys and under ...
Induction motor
An induction or asynchronous motor is an AC electric motor in which the electric current in the rotor needed to produce torque is obtained by electromagnetic induction from the magnetic field of the stator winding. An induction motor therefore does not require mechanical commutation, separate-excitation or self-excitation for all or part of the energy transferred from stator to rotor, as in universal, DC and large synchronous motors. An induction motor's rotor can be either wound type or squirrel-cage type.Three-phase squirrel-cage induction motors are widely used in industrial drives because they are rugged, reliable and economical. Single-phase induction motors are used extensively for smaller loads, such as household appliances like fans. Although traditionally used in fixed-speed service, induction motors are increasingly being used with variable-frequency drives (VFDs) in variable-speed service. VFDs offer especially important energy savings opportunities for existing and prospective induction motors in variable-torque centrifugal fan, pump and compressor load applications. Squirrel cage induction motors are very widely used in both fixed-speed and variable-frequency drive (VFD) applications. Variable voltage and variable frequency drives are also used in variable-speed service.