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This is a more complicated question then first meets the eye.
First, the direct answer. Synchronous or Asynchronous motors can work.
However, varying speed in an AC motor can only be done by changing the frequency. This requires the use of a Variable Frequency Drive (Like the Altivar series of drives). A variable frequency drive can create noise on the output, thus you may need filter, and the motor should have inverter duty windings.
If the motor does not have inverter duty windings, then you may not be able to reduce the speed much. Also, when running a motor at a slower speed, you will need to determine the minimum speed that will allow proper torque to the load, as well as still maintain cooling of the motor coils.
Putting a drive onto a motor may require the assistance of a licensed engineer.
Wiki User
∙ 11y ago
Wiki User
∙ 11y agoWithout any modification to its number of operating poles or alteration to the supply frequency, all three phase induction motors are fixed speed motors.
However their speeds can be varied in two ways.
1. A manufacturer design the motor such that its number of operational poles at a time can be varied i.e increased or decreased consequently decreasing or increasing the motor speed respectively. These types of motors are usually called two-speed motors owing to the fact that the motor only have two set operational speeds.
2. The second method make use of a VSD, a Variable Speed/ Frequency Drive. This device increases or decreases the frequency of the supply voltage to the motor. Frequency is directly proportional to the motor's speed. Note that you have to enter the frequency or the speed itself at which you want the motor to run.
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What are the advantages of open end winding induction motor over conventional induction motor?
Open ended induction motor - i assume you are talking about split phase induction motor. With these motors old style speed controlling method using external resistors can be used. However this is now obsolete.
Why single phase induction motor has pulsating torque?
according to a mathematical theory the flux produced when an alternating current flows in a single phase winding , this flux is composed of tow equal components which result in tow equal torques , these torques work in opposite direction to each other , hence one causes the rotor to move in a certain direction while the other in the opposite direction . this is the reason why a single phase induction motor instead of its rotor to move in one direction it vibrates. the resultant of these torques is zero. if the motor is caused to move by an external mean say by hand , then the resultant will no longer zero and the motor continue revolving and it speeds up even the external mean is removed, For a single phase induction motor to be a self starting motor some techniques are used like connecting an additional winding called auxiliary winding and a capacitor which in some designs removed automatically when the motor speed come to a certain value while for other designs these elements continue to be connected . Any single phase induction motor is provided by a starting technique so if it vibrates , then this means that the technique is failed
Single phase motor speed is determined by the?
Motor's number of poles.
What happens if the high and low speed wires are switched on a 3 phase motor?
I am guessing that what you are talking about is a two speed motor. The motor should have 6 wires coming out of it. There are two complete sets of three phase windings for each speed. Look on the motor name plate for the wire numbers or sometimes on the inside of the motor junction box. A 2 speed 6 lead motor should have the following markings, 1U 1V 1W for slow 2U 2V 2W for fast. Also check for the two different amp draws for each winding. These types of motors should be run from a reversing type contactor assemble so that individual overloads can be used on each of the high speed windings and on the low speed windings.
What temperature will an object go from a solid and a liquid?
There is no fixed speed for the transition of a substance from the solid phase to the liquid phase. The maximum speed this can happen at is the speed of light as this is how fast the energy can be transferred to a molecule, and there is no minimum speed. Some substances do not melt into a liquid. Instead they make the transition straight from solid phase into gas phase, and this is called sublimation.
If a three phase induction motor runs at a speed greater than synchronous speed?
When an induction motor is pushed over synchronous speed it will become a generator and will deliver power back to the utility.
Can 3 phase induction motor work when one phase is failed?
yes the motor will rotate but less then the rated speed and more heat will be desipated
How many Methods can be use to control the speed of Single Phase Induction Motor?
How many methods can be used to control the speed of Single Phase Induction Motor? 1.injecting emf method 2.by frequency control method 3.induced voltage method
What are the disadvantages of a three phase induction motor?
The primary disadvantage of the three phase induction motor is that speed control is a challenge. But new technology in the form of VFDs (variable speed drives) is now rectifying this situation very effectively. Another disadvantage is that single phase power is common while three phase power is less commonly available.
What are the advantages of open end winding induction motor over conventional induction motor?
Open ended induction motor - i assume you are talking about split phase induction motor. With these motors old style speed controlling method using external resistors can be used. However this is now obsolete.
Why is the speed of synchronous motor is more then induction motor?
Synchronous motors run at synchronous speed. An induction motor that has the same number of poles must run at a sub-synchronous speed to create a second magnetic field (a field that is at a different phase angle) to generate torque.
Will single-phase Induction motor run on one winding once it has been started?
A single-phase induction motor has a main winding and a starting winding. When the motor has run up to normal speed the starting winding can be switched out, but for small motors this is not usually worth the trouble.
Will a single-phase Induction motor run on one winding once it has been started?
A single-phase induction motor has a main winding and a starting winding. When the motor has run up to normal speed the starting winding can be switched out, but for small motors this is not usually worth the trouble.
Can 3 phase induction motor start and run rated speed by 2 phase?
yes, It would run as long as the motor was not coupled to a load. Coupled to a load the motor would have no torque and would stall.
How does a Variable speed transmission work?
Assume a 3 phase AC Induction motor. The speed of the motor is derived by the formula N = (120/f)/P. N speed, f - frequency, P number of poles. In an induction motor P is fixed by the winding. f system frequency. Variable speed drives change the system frequency so that the speed (N) can be varied. Drive is a power electronic device through which the system frequency can be varied
What are the various method of speed control of 3 phase induction motor?
you can control the speed of a motor by changing frequency, increase or decrease the field winding or by voltage regulation. in these method you can controle the speed of athree phese motor SANDEEP SARKAR
Why 3 phase induction motor never atteined sinkronas speed?
Induction motors run at sub synchronous speeds because the slip (difference between synchronous and actual speed) causes, or controls the electric field strength in the motor. As more load is put on the motor, the motor's speed decreases, increasing slip, and increasing the electric field strength.
