In Induction Motors the EMF induced in the Rotor Winding is Mutually Induced EMF. … If the air gap is more the Leakage Flux will be more and the Mutual Flux gets reduced,reducing Rotor Emf,Current and Torque. In Synchronous Machine the Magnetic Flux is set up separately by Field Winding.
Why do alternators have air gaps?
The air gap needs to be large enough to prevent contact between the rotor and stator, taking into account tolerances related to their respective dimensions, loose bearings, and movement that results from deflection during operation.19 мая 2020 г.
What will happen if we increase the air gap in the induction motor?
If the air gap of an induction motor is increased, the following will happen: The permeability of the magnetic circuit rotor-to-stator will decrease. … The magnetic flux in the air gap will decrease and leakage fluxes will increase. This will cause a reduction in the maximum available torque.
What is the value of air gap in induction motor?
Due to an interaction of the rotor current and the main flux, the torque is produced and the motor starts rotating. In the stator the electric energy is get converted into magnetic energy. The magnetic energy travels through the air gap of the motor. The air gap increase the reluctance of the magnetic circuit.
What is meant by air gap line?
Air gap, also airgap1) or air-gap2) – is a non-magnetic part of a magnetic circuit. It is usually connected magnetically in series with the rest of the circuit, so that a substantial part of the magnetic flux flows through the gap. Diagram of an air gap in a magnetic circuit.
How do I check the air gap on my alternator?
Originally Answered: how much air gap length in alternator? Around 1 to 1.5 mm. It can be checked by inserting a plastic feeler gauge between the stator and rotor. It should be uniform all round.
Why is there an air gap between rotor and stator?
The longer air gap thickness between the motor stator and the rotor, the more cooling liquid flowing through the air gap, which results the heat exchange becomes better between the motor and the cooling liquid and the temperature rise of the motor is lower.
What is the relation between the power factor and the air gap length?
What is the relation between the power factor and the air gap length? Explanation: If the air gap length is small, the dispersion coefficient decreases. As the dispersion coefficient decreases, the power factor increases.
Which starting method is the best method in induction motor?
Starting of an Induction Motor
- Direct on line starter. The direct on line starter method, of an induction motor is simple and economical. …
- Star delta starter. The star delta starter method of starting three phase induction motors is very common and widely used among all the methods. …
- Auto transformer starter.
What is overload capacity of induction motor?
Overload capacity: overload capacity decreased with high value of ac. The value of ac depends upon the size of the motor, voltage of stator winding, type of ventilation and overload capacity desired. It varies between 5000 – 450000 ampere conductors per meter.
What is the effect of an air gap in a magnetic circuit?
Also, the air gaps help the magnetic flux to expand outside the magnetic circuit. This flux fringes out into the neighbouring air path and such paths for flux are called flux fringing resulting in a non-uniform flux density in the air gap. As we increase the air gap, it increases flux fringing and vice versa.
What is the effect of increasing the rotor resistance on starting current and torque?
From Fig. 7.14, a high rotor resistance will provide a high starting torque, leading to rapid acceleration of the mechanical system. This is desirable because short acceleration times reduce the stress on the power system caused by high starting currents.
Which braking method is the best method for obtaining high braking torque?
Do I need an air gap?
Air gaps are the most effective means of preventing your drain from cross-contaminating your dishwasher with waste. If you want to protect your dishwasher from flooding with contaminated water, you need an air gap. Dishwasher air gaps are also required by plumbing codes in many locations.11 мая 2020 г.
What is the difference between an air gap and an air break?
An air break provides a physical separation between the fixture indirect waste pipe and the receptor. … The drainage air gap (see Figure 801.2c) is defined as the vertical distance as measured from the lowest point of the indirect waste pipe or fixture outlet to the overflow rim of the receptor.
Should water come out of the air gap?
Water coming out the air gap should not be a regular occurrence, though occasionally it might happen when, for example, someone forgets to run the garbage disposal. Regular water discharge from an air gap points to a restriction in the water flow.