chap02_dc machines_230107
... that produce the main flux in the machines. The magnetic field of the field winding is approximately sinusoidal, thus AC voltage is induced in the armature winding as the rotor turns under the magnetic field of stator. The COMMUTATOR and BRUSH combination converts the AC generated voltages to DC. ...
... that produce the main flux in the machines. The magnetic field of the field winding is approximately sinusoidal, thus AC voltage is induced in the armature winding as the rotor turns under the magnetic field of stator. The COMMUTATOR and BRUSH combination converts the AC generated voltages to DC. ...
What will happen when when armature winding of a dc shunt motor
... current is held constant during loading, the core loss too can be assumed to remain same. In this test, the motor is run at rated speed under no load condition at rated voltage. The current drawn from the supply IL0 and the field current If are recorded. Since the motor is operating under no load co ...
... current is held constant during loading, the core loss too can be assumed to remain same. In this test, the motor is run at rated speed under no load condition at rated voltage. The current drawn from the supply IL0 and the field current If are recorded. Since the motor is operating under no load co ...
Brushless DC Motors – Part I: Construction and Operating Principles
... Hall Sensor Failure – In sensor-based BLDC motors, rotation of the motor is based solely on the feedback obtained from the Hall sensors. Thus, in case of failure of the Hall sensors, the commutation sequence will break, which may cause the BLDC motor to become stuck and the current to rise above a p ...
... Hall Sensor Failure – In sensor-based BLDC motors, rotation of the motor is based solely on the feedback obtained from the Hall sensors. Thus, in case of failure of the Hall sensors, the commutation sequence will break, which may cause the BLDC motor to become stuck and the current to rise above a p ...
Iowa State University
... or embedded into the rotor slots. At both ends of the rotor, short-circuiting rings are welded or brazed to the bars to make a solid structure. The short-circuited bars, because their resistance is much less than the core, do not have to be specially insulated from the core. In some rotors the bars ...
... or embedded into the rotor slots. At both ends of the rotor, short-circuiting rings are welded or brazed to the bars to make a solid structure. The short-circuited bars, because their resistance is much less than the core, do not have to be specially insulated from the core. In some rotors the bars ...
ENERGY CONVERSION ONE
... • on larger generator & motors, brushless exciters are used • Brushless Exciter: is a smaller ac generator with its field circuit mounted on stator & its armature circuit mounted on rotor shaft - 3 phase output of exciter generator rectified by a 3 phase rectifier mounted also on shaft • By controll ...
... • on larger generator & motors, brushless exciters are used • Brushless Exciter: is a smaller ac generator with its field circuit mounted on stator & its armature circuit mounted on rotor shaft - 3 phase output of exciter generator rectified by a 3 phase rectifier mounted also on shaft • By controll ...
BT044436441
... ISSN : 2248-9622, Vol. 4, Issue 4( Version 1), April 2014, pp.436-441 distributed winding), or can be wound as one coil on the magnetic pole. The magnetization of the permanent magnets and their displacement on the rotor are chosen in such a way that the back-EMF shape is trapizoidal. This allows th ...
... ISSN : 2248-9622, Vol. 4, Issue 4( Version 1), April 2014, pp.436-441 distributed winding), or can be wound as one coil on the magnetic pole. The magnetization of the permanent magnets and their displacement on the rotor are chosen in such a way that the back-EMF shape is trapizoidal. This allows th ...
UNIT-IV 1 Mark questions
... 14. A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A.The torque produced when the armature current is 20 A, is (a) 54 N-m (b) 81 N-m (c) 108 N-m (d) None of the above 15. The d.c. series motor should never be switched on at no load because (a) the field current is zero ...
... 14. A 220 V shunt motor develops a torque of 54 N-m at armature current of 10 A.The torque produced when the armature current is 20 A, is (a) 54 N-m (b) 81 N-m (c) 108 N-m (d) None of the above 15. The d.c. series motor should never be switched on at no load because (a) the field current is zero ...
here
... appearance of pulsation is disturbing, especially during start-up, and pulsation is not desired for higher speeds due to its effect of generating vibration in the masses, which may cause a surplus load and fatigue in the structure. The non-sinusoidal and square-wave supply can be realised at the low ...
... appearance of pulsation is disturbing, especially during start-up, and pulsation is not desired for higher speeds due to its effect of generating vibration in the masses, which may cause a surplus load and fatigue in the structure. The non-sinusoidal and square-wave supply can be realised at the low ...
Lecture-07
... In case of a concentrated winding, all the conductors / pole is housed in one slot. Since the conductors / slot is more, quantity of insulation in the slot is more, heat dissipation is less, temperature rise is more and the efficiency of operation will be less. Also emf induced in the armature condu ...
... In case of a concentrated winding, all the conductors / pole is housed in one slot. Since the conductors / slot is more, quantity of insulation in the slot is more, heat dissipation is less, temperature rise is more and the efficiency of operation will be less. Also emf induced in the armature condu ...
File - electro science club
... Nicholas Callan of Maynooth College, Ireland in 1836. He was one of the first researchers to realize that the more turns the secondary winding has in relation to the primary winding, the larger is the increase in EMF. Induction coils evolved from scientists' and inventors' efforts to get higher volt ...
... Nicholas Callan of Maynooth College, Ireland in 1836. He was one of the first researchers to realize that the more turns the secondary winding has in relation to the primary winding, the larger is the increase in EMF. Induction coils evolved from scientists' and inventors' efforts to get higher volt ...
Experiment No. 1 Study of Separately
... A dc Motor/Generator can run either as a motor or as a generator. A motor converts electrical power into mechanical power while a generator converts mechanical power into electrical power. A generator must, therefore, be mechanically driven in order to produce electricity. Since the field winding is ...
... A dc Motor/Generator can run either as a motor or as a generator. A motor converts electrical power into mechanical power while a generator converts mechanical power into electrical power. A generator must, therefore, be mechanically driven in order to produce electricity. Since the field winding is ...
ED EX 702QUES - St. Aloysius Institute of Technology, Jabalpur
... 46. How electrical power is generated by an A.C Generator? Answer: For the generation of elect power we need a prime mover which supplies mechanical power input to the alternator, can be steam turbines,or hydro turbines .When poles of the rotor moves under the armature conductors which are placed on ...
... 46. How electrical power is generated by an A.C Generator? Answer: For the generation of elect power we need a prime mover which supplies mechanical power input to the alternator, can be steam turbines,or hydro turbines .When poles of the rotor moves under the armature conductors which are placed on ...
EET 2150 — Electric Machines Theory - City Tech
... constants, voltage regulation and efficiency. 3.2 Analyze the various connections of the three phase transformer and their corresponding output 4.1 Discussions will include the National Power Grid, DC power transmission, Super Conductors, and OSHA. ...
... constants, voltage regulation and efficiency. 3.2 Analyze the various connections of the three phase transformer and their corresponding output 4.1 Discussions will include the National Power Grid, DC power transmission, Super Conductors, and OSHA. ...
M.D. Sumption, J. P Murphy, N N. Gheorghiu, T. Haugan, M. Majoros
... deliver power to motor-driven fans positioned along the wings. There is some power loss associated with the conversion, this is more than made up for by the increased efficiency by what is in effect an enhancement of the fan by-pass ratio. o YBCO coated conductor is of great interest because of its ...
... deliver power to motor-driven fans positioned along the wings. There is some power loss associated with the conversion, this is more than made up for by the increased efficiency by what is in effect an enhancement of the fan by-pass ratio. o YBCO coated conductor is of great interest because of its ...
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.