ACM - JNEC
... and low reactance. The resistance of the starting winding may be increased either by connecting a high resistance R in series with it or by using a high resistance fine copper wire for winding purposes. Hence as shows in fig.3 the current Is drawn by the starting winding logs behind the applied volt ...
... and low reactance. The resistance of the starting winding may be increased either by connecting a high resistance R in series with it or by using a high resistance fine copper wire for winding purposes. Hence as shows in fig.3 the current Is drawn by the starting winding logs behind the applied volt ...
Pdf - Text of NPTEL IIT Video Lectures
... and it has two brushes. So the armature makes contact with the electrical world by the means of these two brushes and the armature winding resistance is represented as an equivalent resistance R a as shown here. There is a source which is applied a source voltage which is applied and we call that on ...
... and it has two brushes. So the armature makes contact with the electrical world by the means of these two brushes and the armature winding resistance is represented as an equivalent resistance R a as shown here. There is a source which is applied a source voltage which is applied and we call that on ...
Determination of Rotor Slot Number of an Induction Motor Using an
... In this paper a method for the prediction of the number of slots of an induction motor is proposed. The approach is based on FFT analysis of the induced voltage in an external search coil. It is shown that the method works well irrespective of whether the motor is driven by the mains voltage or via ...
... In this paper a method for the prediction of the number of slots of an induction motor is proposed. The approach is based on FFT analysis of the induced voltage in an external search coil. It is shown that the method works well irrespective of whether the motor is driven by the mains voltage or via ...
presentation for slide
... Other dynamic aspects of load components include: Extinction of discharge (mercury vapour, sodium vapour, fluorescent) lamps when voltage drops below 0.7 to 0.8 pu and their restart after 1 or 2 seconds delay when voltage recovers. Operation of protective relays. For example, starter contractors ...
... Other dynamic aspects of load components include: Extinction of discharge (mercury vapour, sodium vapour, fluorescent) lamps when voltage drops below 0.7 to 0.8 pu and their restart after 1 or 2 seconds delay when voltage recovers. Operation of protective relays. For example, starter contractors ...
CPO Science Link Teacher`s Guide
... electromagnets work together to make electric motors. The secret to making an electric motor work is in the ability of an electromagnet to reverse its north and south poles. In this investigation, students first try to make the rotor spin by manually flipping permanent magnets near the rotor magnets ...
... electromagnets work together to make electric motors. The secret to making an electric motor work is in the ability of an electromagnet to reverse its north and south poles. In this investigation, students first try to make the rotor spin by manually flipping permanent magnets near the rotor magnets ...
experiment - UniMAP Portal
... Characteristics of a Three-Phase Synchronous Motor 11. Change the value of resistor R, and vary the setting of the EXCITER knob on the Synchronous Motor/Generator so that the field current passes from the minimum current to the maximum current indicated in the following Table 6.1, in ten steps that ...
... Characteristics of a Three-Phase Synchronous Motor 11. Change the value of resistor R, and vary the setting of the EXCITER knob on the Synchronous Motor/Generator so that the field current passes from the minimum current to the maximum current indicated in the following Table 6.1, in ten steps that ...
Control And Modeling Of Doubly Fed Induction Machine For
... generator used in variable-speed wind power generation. And a control structure using standard proportional integral PI controller and a field-oriented control strategy based on a reference frame rotating synchronously with the rotor flux for variable speed wind turbines using doubly fed induction g ...
... generator used in variable-speed wind power generation. And a control structure using standard proportional integral PI controller and a field-oriented control strategy based on a reference frame rotating synchronously with the rotor flux for variable speed wind turbines using doubly fed induction g ...
Mechanical Dissection Laboratory Power Hand Drill Instructors : Drs
... you'll encounter some resistance to that movement. That resistance is called friction. Energy is required to overcome friction, but friction is not necessarily a disadvantage. The friction between the wheels of a car and roadway not only keep the car from skidding, but enable the car to move in the ...
... you'll encounter some resistance to that movement. That resistance is called friction. Energy is required to overcome friction, but friction is not necessarily a disadvantage. The friction between the wheels of a car and roadway not only keep the car from skidding, but enable the car to move in the ...
ME 486 - Automation Building Blocks
... stator rather than slots. The result is a smoother surface facing the magnet. This design also reduces cogging by eliminating variation in attractive force. Tubular linear motors roll up the unit about an axis parallel to its length. In one style, an outer thrust block carrying the motor coils envel ...
... stator rather than slots. The result is a smoother surface facing the magnet. This design also reduces cogging by eliminating variation in attractive force. Tubular linear motors roll up the unit about an axis parallel to its length. In one style, an outer thrust block carrying the motor coils envel ...
doubly fed induction generator in a wind turbine
... turbine is given by the pitch angle and the tip speed ratio. Adjustable speed will improve the system efficiency since the turbine speed can be adjusted as a function of wind speed to maximize output power. To develop adjustable speed one possible solution is a doubly fed induction generator. A dyna ...
... turbine is given by the pitch angle and the tip speed ratio. Adjustable speed will improve the system efficiency since the turbine speed can be adjusted as a function of wind speed to maximize output power. To develop adjustable speed one possible solution is a doubly fed induction generator. A dyna ...
Experiment 2
... four. The main difference is that the second phase is turned on before the first phase is turned off. Thus, sometimes both phases are energized at the same time. During the half-steps the rotor is held in between the two full-step positions. A half-step motor has twice the resolution of a full step ...
... four. The main difference is that the second phase is turned on before the first phase is turned off. Thus, sometimes both phases are energized at the same time. During the half-steps the rotor is held in between the two full-step positions. A half-step motor has twice the resolution of a full step ...
High Efficiency Squirrel Cage Induction Machines
... field computation domain, Fig. 2, includes 7820 second order elements of triangle shape with smaller size towards the air-gap where the most part of the magnetic energy of the machine is concentrated. ...
... field computation domain, Fig. 2, includes 7820 second order elements of triangle shape with smaller size towards the air-gap where the most part of the magnetic energy of the machine is concentrated. ...
What is being measured
... Lead Isolation [II] (patient sink) current is that current that would flow into the device undertest, if the patient were to come into contact with full line voltage. This could occur again with an electric bed, but which has become ungrounded, and has a short to the frame. While measurement is made ...
... Lead Isolation [II] (patient sink) current is that current that would flow into the device undertest, if the patient were to come into contact with full line voltage. This could occur again with an electric bed, but which has become ungrounded, and has a short to the frame. While measurement is made ...
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.