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Field control of DC motor

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Field control of DC motor

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•In field control of DC motor terminal voltage is kept constant.

•The field flux (φ_f) is directly proportional to the field current (I_f) .

•Speed (N) is inversely proportional to field flux (φ_f) .

•So as the field flux (φ_f) will be less speed (N) will be more.

•If the current is less field flux (φ_f)  is less hence the speed (N) will be more.

•We can control speed by field diverter method or by using tapped field control.

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Field control of DC motor

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