How speed control of DC motor can be achieved?

1.	How speed control of DC motor can be achieved?
Answer» Induced emf in the armature E = P * φ * Z * N / A * 60 volts. Where Z and A are constant. N ∝ E_b / φ N ∝ V – I_a r_a / φ. We can consider that the I_a r_a drop is very small and there by in the place of V – I_a r_awe can consider only V. If it so then N ∝ V/ φ. So speed may be varied by varying either applied voltage to the armature and by varying field flux or field strength per pole or total field flux.

Answer»

Induced emf in the armature E = P * φ * Z * N / A * 60 volts.

Where Z and A are constant.

N ∝ E_b / φ

N ∝ V – I_a r_a / φ.

We can consider that the I_a r_a drop is very small and there by in the place of V – I_a r_awe can consider only V. If it so then N ∝ V/ φ.

So speed may be varied by varying either applied voltage to the armature and by varying field flux or field strength per pole or total field flux.

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How speed control of DC motor can be achieved?

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