A dc machine is rated at 5.0 hp with vf = 240 V, va = 240...
A dc machine is rated at 5.0 hp with vf = 240 V, va = 240 V, and ωr = 127.7 rad∙s-1 . The armature/field mutual inductance is 1.80 H, the armature resistance is 0.63 Ω, and the field winding resistance is 240 Ω.
The machine is to be operated at ωr = 2ωrR in field-weakening mode with va = vaR and ia = iaR.
a. Calculate the load torque.
b. Now, the load torque is reduced by one-half of the value determined in part (a).
i. Calculate ia for va = vaR.
ii. Calculate va for ia = iaR.
Homework Answers
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otor shown below is controlled by the armature voltage va and load torque ease i ngular velocity w, and ts is the back-emf generated by op a model (first order differential equation) of armature current i in terms velop a model (irst order differential equation) of motor output speed w in terms ta and w as state variables, and va and Ti as inputs, write the state equations the motor. complete the following of motor output speed w and input...
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