INDUSTRIAL APPLICATIONS Synchronous motors rated at 20 horsepower (hp) or more are used for constant speed applications. They are used to drive large air and gas compressors that must be operated at a fixed speed to maintain a constant output at the maximum efficiency. Synchronous motors are used to drive dc generators, fans, blowers, and […]
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Alternating current fundamentals
The Synchronous Motor: Industrial applications.
INDUSTRIAL APPLICATIONS Synchronous motors rated at 20 horsepower (hp) or more are used for constant speed applications. They are used to drive large air and gas compressors that must be operated at a fixed speed to maintain a constant output at the maximum efficiency. Synchronous motors are used to drive dc generators, fans, blowers, and […]
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The Synchronous Motor: Load on a synchronous motor and Power factor .
LOAD ON A SYNCHRONOUS MOTOR When the mechanical load is increased on a dc motor or an ac induction motor, there is a decrease in the speed. This decrease results in a reduction of the counterelectromotive force. Thus, the source can supply more current to meet the increased load demands. This method of compensating for […]
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The Synchronous Motor: Load on a synchronous motor and Power factor .
LOAD ON A SYNCHRONOUS MOTOR When the mechanical load is increased on a dc motor or an ac induction motor, there is a decrease in the speed. This decrease results in a reduction of the counterelectromotive force. Thus, the source can supply more current to meet the increased load demands. This method of compensating for […]
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The Synchronous Motor: Construction , Operating principles and DC field excitation .
The Synchronous Motor CONSTRUCTION The three-phase synchronous motor consists of the following components: • A laminated stator core with a three-phase armature winding • A revolving field with an amortisseur winding and slip rings • Brushes and brush holders • Two end shields housing the bearings that support the rotor shaft The stator core and […]
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The Synchronous Motor: Construction , Operating principles and DC field excitation .
The Synchronous Motor CONSTRUCTION The three-phase synchronous motor consists of the following components: • A laminated stator core with a three-phase armature winding • A revolving field with an amortisseur winding and slip rings • Brushes and brush holders • Two end shields housing the bearings that support the rotor shaft The stator core and […]
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Three-Phase Induction Motors: Comparison between squirrel-cage and woundrotor induction motors.
COMPARISON BETWEEN SQUIRREL-CAGE AND WOUND-ROTOR INDUCTION MOTORS The wound-rotor induction motor has the following advantages: • High starting torque and low starting current if the motor is started with the maximum resistance inserted in the rotor circuit • Variable speed • Smooth acceleration under heavy loads There are several disadvantages to this motor, including the […]
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Three-Phase Induction Motors: Comparison between squirrel-cage and woundrotor induction motors.
COMPARISON BETWEEN SQUIRREL-CAGE AND WOUND-ROTOR INDUCTION MOTORS The wound-rotor induction motor has the following advantages: • High starting torque and low starting current if the motor is started with the maximum resistance inserted in the rotor circuit • Variable speed • Smooth acceleration under heavy loads There are several disadvantages to this motor, including the […]
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Three-Phase Induction Motors: Single-phase operation of three-phase induction motors , The wound-rotor induction motor , Reverse rotation , Operating characteristics and Terminal markings .
SINGLE-PHASE OPERATION OF THREE-PHASE INDUCTION MOTORS A line wire feeds the stator windings of a three-phase induction motor. If this wire is opened, the motor will operate as a single-phase induction motor. It will not have enough torque to start when energized from a single-phase source. However, if the three-phase motor is running when the […]
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Three-Phase Induction Motors: Single-phase operation of three-phase induction motors , The wound-rotor induction motor , Reverse rotation , Operating characteristics and Terminal markings .
SINGLE-PHASE OPERATION OF THREE-PHASE INDUCTION MOTORS A line wire feeds the stator windings of a three-phase induction motor. If this wire is opened, the motor will operate as a single-phase induction motor. It will not have enough torque to start when energized from a single-phase source. However, if the three-phase motor is running when the […]
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