What is the relation of the type of winding with the flux linkage?

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Examoogle · Accepted Answer

in distributed windings, the flux does not link with all the turns

Explanation: In a distributed winding, individual coils are placed in multiple slots under a single pole, causing each turn to link with a different portion of the magnetic flux. Consequently, the total flux linkage is the sum of the fluxes linked by individual coils at different spatial positions, which prevents all turns from linking with the peak magnetic flux simultaneously.

Working Principle: Due to the spatial distribution of coils in slots, the induced EMFs in different coils are phase-shifted relative to each other. This results in a distribution factor $k_d

Key Formulas: $k_d = \frac{\sin(m\beta/2)}{m\sin(\beta/2)}$ — Distribution factor where $m$ is slots/pole/phase and $\beta$ is slot angle; $\Phi_{total} = \sum \Phi_i$ — Total flux linkage in distributed system

Key Points: Distributed windings reduce harmonics and produce a more sinusoidal EMF waveform.; Concentrated windings link the maximum possible flux per turn as all turns are in the same slot.; The use of distributed windings significantly improves the performance of AC machines.

Advantages: Better utilization of armature core; Improved heat dissipation; Reduction in harmonics

Disadvantages: Lower induced EMF compared to concentrated winding; Complex manufacturing process

Applications: AC Generators (Alternators); Induction Motors

Additional Info: In concentrated windings, all turns are grouped in one slot, ensuring they link the same magnetic flux.. Option B is incorrect because distributed windings imply spatial displacement that prevents uniform flux linking.

Answer: A is correct — in distributed windings, the spatial displacement of coils results in the flux not linking with all turns equally, leading to a reduced overall induced EMF.

Exam Tip: Always remember that distributed windings are used to improve the waveform shape, even at the cost of reduced overall induced voltage magnitude.

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