Question 81Electricity/Electronics - Assistant Engineer70% to pass
When a compound wound DC motor is differentially compounded, what does this mean?
AI Explanation
The correct answer is C) The current flow direction in each series-field coil is in the opposite direction as the current flow direction in its corresponding shunt-field coil, in which case the field fluxes are subtractive.
In a differentially compounded DC motor, the series-field coils and the shunt-field coils are connected in such a way that their magnetic fields oppose each other. This means that the current flow direction in the series-field coils is in the opposite direction of the current flow in the corresponding shunt-field coils. As a result, the magnetic fields produced by the series and shunt windings subtract from each other, leading to a weaker overall magnetic field.
The other options are incorrect because they describe scenarios where the series and shunt field fluxes are either additive or the current flow directions are the same, which is not the case in a differentially compounded DC motor.
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