Slip ring (wound rotor) Induction Motor : In slip ring induction motors the rotor is wound type. In the motor the slip rings, brushes are provided. Compared to squirrel cage rotor the rotor construction is not simple. Cylindrical laminated core rotor is wound for as the number of poles of the stator.
A compound wound DC motor or rather a DC compound motor falls under the category of self excited motors, and is made up of both series the field coils S 1 S 2 and shunt field coils F 1 F 2 connected to the armature winding as shown in the figure below.
Compound Wound DC Motor or DC Compound Motor A compound wound DC motor or rather a DC compound motor falls under the category of self excited motors, and is made up of both series the field coils S 1 S 2 and shunt field coils F 1 F 2 connected to the armature winding as shown in the figure below.
Small DC motors are used in tools, toys, and appliances. The universal motor can operate on direct current but is a lightweight motor used for portable power tools and appliances. Larger DC motors are used in propulsion of electric vehicles, elevator and hoists, or in drives for steel rolling mills.
When the double cage motor is running at normal speed, frequency of the rotor emf is so low that the reactance of both cages is negligible. The two cages being connected in parallel, the combined resistance is lower. The torque speed characteristics of double squirrel cage motor for both the cages are shown in the figure below.
Electrical excited DC motor: If no current is running through the stator coil, the motor rotates anticlockwise. That's caused by the interaction between the magnetic field of the armature's coil and the iron core of the stator (see Energy of magnetic fields).
Coreless DC Motor Technology Coreless DC motors differ from traditional DC motors in significant ways. The most obvious and important difference is the rotor winding. Instead of coils wound around a stack of iron laminations, the coil is formed as a thin hollow cylinder (item 1 above). The stator with its permanent magnets (item 2) supplies the magnetic field flux and fits in the hollow center ...
Construction of Permanent Magnet DC Motor or PMDC Motor As it is indicated in name of permanent magnet DC motor, the field poles of this motor are essentially made of permanent magnet. A PMDC motor mainly consists of two parts. A stator and an armature. Here the stator which is a steel cylinder. The magnets are mounted in the inner periphery of this cylinder.
Advantages of Permanent Magnet DC Motor or PMDC Motor PMDC motor have some advantages over other types of DC motors. They are : No need of field excitation arrangement. No input power in consumed for excitation which improve efficiency of DC motor. No field coil hence space for field coil is saved which reduces the overall size of the motor.
A series wound DC motor like in the case of shunt wound DC motor or compound wound DC motor falls under the category of self-excited DC motors, and it gets its name from the fact that the field winding in this case is connected internally in series to the armature winding.
Principle of Operation Synchronous Motor Synchronous motor is a doubly excited machine, i.e. two electrical inputs are provided to it. Its stator winding which consists of a We provide three-phase supply to three-phase stator winding, and DC to the rotor winding.