Why do we need air gap in a magnetic circuit?

Why do we need air gap in a magnetic circuit?

In this circuit, there is only one path for the magnetic circuit and thus it can be called as a series magnetic circuit. One of main reasons for an Air Gap is to increase the reluctance of the magnetic circuit. Also, the air gaps help the magnetic flux to expand outside the magnetic circuit.

What is the purpose of air gap in solenoid design?

Air gaps are an integral part of gapped inductors. The gap reduces effective permeability of a given magnetic circuit and allows storing much greater energy before saturation is reached. Increasing the gap reduces the inductance, so the winding must have more turns to compensate accordingly.

How would an air gap in the magnetic path affect the performance of the transformer?

In the case of a transformer or inductor, the air gap only reduces the slope of the B/H loop, reducing permeability and inductance, and hence increasing the magnetizing current in the primary. Thus, in the transformer example, the gap is used to reduce the inductance (perhaps for resonant applications).

How is the voltage related with the air gap density?

How is the voltage related with the air gap density? Clarification: The air gap density is indirectly proportional to the voltage. High voltage machine should have low air gap density, to avoid excessive values of flux density in the teeth and core.

What is the formula for MMF of air gap?

According to the formula (3), the total value of MMF of the magnetic circuit is FΣ1=430+2·36+2·51+180+3,9=788 А. The saturation coefficient of the magnetic circuit is the ratio of the total MMF of the magnetic circuit FΣ to the total value of MMF of the magnetic circuit in the air gap Fδ.

What is the value of air gap permeability?

The air gap is typically quite small when compared to the core’s entire magnetic path length. Gaps are typically 0.001” to 0.1” (0.00254 to 0.25cm) compared to typical path lengths of 20-100cm for parts up to the size of a human fist. Air gaps can be ground into the center leg using a wet grinding technique.

How do I find my air gap power?

Air Gap Power in Induction Motor

  1. Core Losses or No Load Losses. The loss comprises the eddy current and hysteresis loss.
  2. PstL=Ps(h+e)+Ps ————–(2) Where,
  3. The air gap power(Pg) can be calculated as;
  4. Pg=√3VL x IL cosΦ-[(Ps(h+e)+Ps)] ——(3)
  5. The air gap Power= Rotor Input Power.
  6. Calculation of Air Gap Power.

Why do we need air gap?

An air gap is a simple way to make certain wastewater and contaminants never re-enter your clean water supply. There is enough distance between the mouth of the faucet and the sink’s rim to ensure that dirty water will never backflow into your kitchen faucet and pollute the clean water supply.

What factors does the value of magnetising current depends on?

How many factors does the value of the magnetizing current depends upon? Explanation: There are 3 factors upon which the magnetizing current depends upon. They are total mmf required, number of turns in the exciting winding and upon the way in which the winding is distributed.

Which factors modify the reluctance of air gap?

The virtue of the air gap is that, because it is free from ferromagnetic material, it does not suffer any change of reluctance with flux level. Its reluctance depends only on its length, lg, and cross sectional area, Ae; and both of those parameters you can make very stable.

What is the length of the air gap?

For small PM synchronous motors, the air gap (mechanical clearance) between the stator core and rotor poles or pole shoes should be 0.3 to 1.0 mm [6,8], and can even reach 1.5 mm [9]. The smaller the air gap, the lower the starting current drawn by the motor.

Why do we need an air gap in magnetic circuit?

An air gap is a non-magnetic part of a magnetic circuits and it is usually connected magnetically in series with the rest of the circuit. This allows a substantial part of the magnetic flux flows through the gap.

What are the roles of air gap flux in an electric motor?

The air gap can take different form, shape and size depending on the type of magnetic circuit and its shape. In some circuits it might be actually an integral part ensuring correct performance of the device, but in other cases it should be as small as possible.

How is the air gap used to calculate reluctance?

To calculate reluctance: The air gap is mostly used in applications where the magnetic saturation concludes as a high risk as magnetic saturation causes loss of inductance, increasing of current, power loss in the circuit.

Why is there an air gap in a transformer?

But sometimes in transformer the air gap fails to prevent saturation caused by excessive AC voltage polarization. Air is a non-magnetic part of a magnetic circuit that connects serially and magnetically all the other parts in the circuit to make the flux to flow through the gap.

Why do we need air gap in a magnetic circuit? In this circuit, there is only one path for the magnetic circuit and thus it can be called as a series magnetic circuit. One of main reasons for an Air Gap is to increase the reluctance of the magnetic circuit. Also, the air gaps help…