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One way is to add a capacitor and some extra field windings.
Starters are needed because the starting current in an motor may go as high as 6-7 times its rated current.
Some of the methods used for starting motors are,
Direct online starters, Auto Transformers, Soft Starters, Variable Speed Drives, Intelligent Motor Controls.
Wiki User
∙ 11y ago
Wiki User
∙ 8y agoThe two basic types are induction and synchronous. Induction motors are more common but for high-power continuous use synchronous motors are preferred because they can be adjusted to present a good power factor to the supply.
Answer
'Synchronous motors' are not induction motors, because the rotor currents are not 'induced' by the stator currents, and (due to the inertia of the rotors) are not self-starting. On larger machines, starting is accomplished by means of a pony motor.
The two types of three-phase induction motor are the 'squirrel cage' and 'wound' rotor types.
In both cases, current is induced into the rotor by the naturally-rotating stator field. Thanks to the advent of industrial electronics, wound rotor motors are relatively unusual these days, but use slip rings and external resistors to vary the magnitude of the rotor current in order to achieve speed control. Industrial electronics allow the speed control of squirrel cage motors by varying the supply frequency.
Wiki User
∙ 10y ago47
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Which motor is used in electric train and traction?
An electric train uses electric motors. Modern trains have many motors, they are mounted on the axles, one motor per axle. Some axles will be powered and have motors on them, some will not.
How many types of AC generator are there?
Induction type alternator and synchronous generator.
What is an ac motor?
An AC motor is an electric motor that runs on alternating current, like household electricity, as opposed to a DC motor that runs on direct current from a battery. Most AC motors work from the mains supply, which has a frequency of 50Hz in the UK and 60Hz in the USA. Other types are available that work like stepper motors and need a specialist supply to run them.
Three basic type of dc motor?
hair dryer, cars ,lawnmower ,generator ,computer ,pool ,cleaner ,tv ,plane ,cell phone ,fans ,heaters ,remote contrl car ,boat For DC: Permanent magnet brush motor; (uses fixed magnets for stator fields); toys and automotive use Shunt field motor; (field winding has many turns of fine wire in parallel with armature) small machines; Series field motor; (field winding has few turns of heavy wire in series with armature); high speed, high torque; Compound field motor; (has both series and shunt fields); large machinery, general purpose workhorses; Brushless DC motors (use electronics to switch stator windings on and off, and have permanent magnet rotors) small fans and light loads. For single phase AC: Split Phase induction motor (2 different windings connected to supply, cage type rotor) low torque, general purpose; Capacitor Start induction motor; (As per split phase, but with capacitor in series with starting winding) high starting torque, general purpose; Capacitor start, Capacitor run induction motor; (as per capacitor start, but different capacitors used for starting and running) high starting and running torque, quietest running; Shaded pole induction motor; (run winding and copper or aluminium ring around part of iron core of stator) small, cheap motors, low torque; Universal motor; (as per series DC motor above) high torque, high speed, poor speed stability. For 2 or 3 phase AC (star or delta connected) Polyphase induction motor (2 or 3 identical windings on stator, cage rotor) general purpose; Wound rotor induction motor (2 or 3 identical windings on stator, wound rotor connected in star to 3 sliprings and external resistance unit) very high starting torque, low starting current; Synchronous motor; (standard stator, and wound rotor connected to DC supply for 'excitation' of rotor field) constant speed, power factor correction.
How many volts do machines with bigger motors take?
It depends on ampage & voltage of the motors involved.
How many microfarad of starting capacitor is best for 15hp 3phase motor?
Starting capacitors are only required for single-phase induction motors. They are not necessary for three-phase motors.
How many types of DC motor?
Types of AC MotorsClassification Based On Principle Of Operation:(a) Synchronous Motors.1. Plain2. Super(b) Asynchronous Motors.1. Induction Motors:(a) Squirrel Cage(b) Slip-Ring (external resistance).2. Commutator Motors:(a) Series(b) Compensated(c) Shunt(d) Repulsion(e) Repulsion-start induction(f) Repulsion induction
Which motor is used in electric train and traction?
An electric train uses electric motors. Modern trains have many motors, they are mounted on the axles, one motor per axle. Some axles will be powered and have motors on them, some will not.
How many types of AC generator are there?
Induction type alternator and synchronous generator.
What are the Applications of induction motors?
Introductionl It is becoming very popular the utilization of squirrel cageinduction motors with variable frequency drives (VFD's) in theindustry.l The advance of power electronics technology and the cost of theVFD's are making this utilization possible.l The many advantages of this type of application are:ÙSpeed variation.ÙHeavy load inertia starting.ÙHigh starting torque requirements.ÙLow starting current requirements.ÙHigh efficiency at low speed.ÙHigh power factor.l The induction motor with VFD's replaces with advantage todaythe DC motors, and wound rotor motors.
What are the names of electrical motors?
There are many types of electric motors. They are things like cars, lawn mowers, and so on.
How many percent will be the starting current for motor?
Motor starting current is typically 5-7 times the rated current of the motor. (For three phase induction motors)
Conclusion of ac motors?
there are many types of ac motor, each of those work on a specific/ certain task. Ac motors are really helpful to world today
How many types of relays?
relays are two type 1. Electromagnetic attraction relays. 2. Electromagnetic induction relays.
What is an ac motor?
An AC motor is an electric motor that runs on alternating current, like household electricity, as opposed to a DC motor that runs on direct current from a battery. Most AC motors work from the mains supply, which has a frequency of 50Hz in the UK and 60Hz in the USA. Other types are available that work like stepper motors and need a specialist supply to run them.
How many amps does a 10kw heater draw that's 3phase 220volt?
40 amps
Explain in detail the constructional details of three phase induction motor?
The stator of an induction motor consists of poles carrying supply current to induce a magnetic field that penetrates the rotor. To optimize the distribution of the magnetic field, the windings are distributed in slots around the stator, with the magnetic field having the same number of north and south poles. Induction motors are most commonly run on single-phase or three-phase power, but two-phase motors exist; in theory, induction motors can have any number of phases. Many single-phase motors having two windings can be viewed as two-phase motors, since a capacitor is used to generate a second power phase 90 degrees from the single-phase supply and feeds it to the second motor winding. Single-phase power is more widely available in residential buildings, but cannot produce a rotating field in the motor, so they must incorporate some kind of starting mechanism to produce a rotating field. There are three types of rotor: squirrel cage rotors made up of skewed (to reduce noise) bars of copper or aluminum that span the length of the rotor, slip ring rotors with windings connected to slip rings replacing the bars of the squirrel cage, and solid core rotors made from mild steel. For information on die-cast copper rotors in energy-efficient induction motors, see: Copper die-cast rotors.
