![External Rotor Motors](http://s1.studyres.com/store/data/006258367_1-a3584b98dbe9337197f9ab51e9e79398-300x300.png)
DC Machines
... A Double layer winding means that each slot will house two coil sides (obviously belonging to two different coils). Physically one coil side is placed in the lower portion of the slot while the other is placed above it. It is because of this reason such an arrangement of the winding is called a doub ...
... A Double layer winding means that each slot will house two coil sides (obviously belonging to two different coils). Physically one coil side is placed in the lower portion of the slot while the other is placed above it. It is because of this reason such an arrangement of the winding is called a doub ...
Generator and Transformer
... Transforms mechanical energy into electric energy Coil of wire spins in the presence of a permanent magnetic field Induces are current in the coil Current produced actually fluctuates as the coils position in the field changes Produces a current that switches direction every half a rotation – Called ...
... Transforms mechanical energy into electric energy Coil of wire spins in the presence of a permanent magnetic field Induces are current in the coil Current produced actually fluctuates as the coils position in the field changes Produces a current that switches direction every half a rotation – Called ...
Brushed DC Motor Basics
... decreasing torque at high speeds and a high but more consistent torque at low speeds. The current in the field coil and in the rotor are independent of one another, thus, the total current of the motor is equal to the sum of the shunt current ( or stator current ) and the rotor current. As a result, ...
... decreasing torque at high speeds and a high but more consistent torque at low speeds. The current in the field coil and in the rotor are independent of one another, thus, the total current of the motor is equal to the sum of the shunt current ( or stator current ) and the rotor current. As a result, ...
DIAGNOSTIC NEWS CSA for Motor Rotor Fault Detection
... losses should not increase by more than about 5 per cent. If the core loss increases by more than 5 per cent, the service shop may have done the “burn out” at too high a temperature, and thus damaged the insulation between the steel laminations. 10. If a motor has been retrofitted with an inverter t ...
... losses should not increase by more than about 5 per cent. If the core loss increases by more than 5 per cent, the service shop may have done the “burn out” at too high a temperature, and thus damaged the insulation between the steel laminations. 10. If a motor has been retrofitted with an inverter t ...
EEEB283 Electrical Machines & Drives
... – Normal IM equations can be used, except s is negative – Only possible for > s when fed from fixed frequency source ...
... – Normal IM equations can be used, except s is negative – Only possible for > s when fed from fixed frequency source ...
Lenzs` Law - PhysicsAPB
... uses very fine wire while the secondary uses much thicker wire. To drop down to 3 volts, there needs to be 40 times more turns in the primary than in the secondary. ...
... uses very fine wire while the secondary uses much thicker wire. To drop down to 3 volts, there needs to be 40 times more turns in the primary than in the secondary. ...
Ch 4 - MyWeb at WIT
... Pull-up torque of an induction motor is the minimum torque developed by the motor from rest to the speed at which breakdown occurs. This is the initial value for ideal motors seen if Fig. 4-11 or the pull-point in motors with imperfections as seen above. Parasitic torques are caused by non-sinusoida ...
... Pull-up torque of an induction motor is the minimum torque developed by the motor from rest to the speed at which breakdown occurs. This is the initial value for ideal motors seen if Fig. 4-11 or the pull-point in motors with imperfections as seen above. Parasitic torques are caused by non-sinusoida ...
(SEIG) or Squirrel Cage Induction Generator
... The mechanical power of a wind turbine is converted into electric power by an alternating current (AC) generator or a direct current (DC) generator. The AC generator can be either a synchronous machine or an induction machine, the latter being the most widely used in the wind power industry. The ele ...
... The mechanical power of a wind turbine is converted into electric power by an alternating current (AC) generator or a direct current (DC) generator. The AC generator can be either a synchronous machine or an induction machine, the latter being the most widely used in the wind power industry. The ele ...
LAB#5 - SIUE
... 2. To observe the characteristics of the wound rotor induction motor at no load and at full load. 3. To observe speed control using an external variable resistance. DISCUSSION The three ends of the three-phase rotor windings are brought out to three slip rings mounted on the rotor shaft. The brushes ...
... 2. To observe the characteristics of the wound rotor induction motor at no load and at full load. 3. To observe speed control using an external variable resistance. DISCUSSION The three ends of the three-phase rotor windings are brought out to three slip rings mounted on the rotor shaft. The brushes ...
Question Bank Solutions
... in the armature always acts in the opposite direction of the supply voltage. This is according to the Lenz's law which states that the direction of the induced e.m.f. is always so as to oppose the cause producing it. In a d c. motor, electrical input i.e. the supply voltage is the cause and hence th ...
... in the armature always acts in the opposite direction of the supply voltage. This is according to the Lenz's law which states that the direction of the induced e.m.f. is always so as to oppose the cause producing it. In a d c. motor, electrical input i.e. the supply voltage is the cause and hence th ...
Commutator (electric)
![](https://commons.wikimedia.org/wiki/Special:FilePath/Universal_motor_commutator.jpg?width=300)
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.