Question

A dc motor has an armature resistance of 1 ?, and K? = 3 Vsec. When...

A dc motor has an armature resistance of 1 ?, and
K? = 3 Vsec. When the motor’s terminal voltage is
adjusted to 320 V, the motor speed is 1000 r/min. A
TVR braking is applied,
a) Calculate the value of the braking resistance that
would reduce the maximum braking current to twice
the rated current.
b) Calculate the new motor steady state speed if the
load is bidirectional and braking resistance is taken
off.

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