At standstill the rms currents in the main and auxiliary

At standstill the rms currents in the main and auxiliary At standstill the rms currents in the main and auxiliary windings of a four-pole, capacitor-start induction motor are/main = 20.7 A and Iaux = 11.1 A respectively. The auxiliary-winding current leads the main-winding current by 53째. The effective turns per pole (i.e., the number of […]

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A shunt motor operating from a 230-V line draws a full-load

A shunt motor operating from a 230-V line draws a full-load A shunt motor operating from a 230-V line draws a full-load armature current of 46.5 A and runs at a speed of 1300 r/min at both no load and full load. The following data is available on this motor: Armature-circuit resistance (including brushes) = […]

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A salient-pole synchronous generator with saturated Xd = 0.78

A salient-pole synchronous generator with saturated Xd = 0.78 A salient-pole synchronous generator with saturated synchronous reactances Xd = 0.78 per unit and Xq = 0.63 per unit is connected to a rated-voltage infinite bus through an external impedance X bus = 0.09 per unit. a. Assuming the generator to be supplying only reactive power […]

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A dc shunt motor operating at an armature terminal voltage

A dc shunt motor operating at an armature terminal voltage A dc shunt motor operating at an armature terminal voltage of 125 V is observed to be operating at a speed of 1180 r/min. When the motor is operated unloaded at the same armature terminal voltage but with an additional resistance of 5 O in […]

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A long, thin solenoid of radius r0 and height h

A long, thin solenoid of radius r0 and height h A long, thin solenoid of radius r0 and height h is shown in figure. The magnetic field inside such a solenoid is axially directed, essentially uniform and equal to H = Ni/h. The magnetic field outside the solenoid can be shown to be negligible. Calculate […]

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Consider a three-phase synchronous motor for which you are given

Consider a three-phase synchronous motor for which you are given Consider a three-phase synchronous motor for which you are given the following data: Rated line-to-line voltage (V), Rated volt-amperes (VA), Rated frequency (Hz) and speed (r/min), Synchronous reactance in per unit, Field current at rated open-circuit voltage (AFNL) (A). The motor is to be operated […]

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Consider the 8-kV: 78-kV, 50-MVA transformer of Problem 2.15 con

Consider the 8-kV: 78-kV, 50-MVA transformer of Problem 2.15 con Consider the 8-kV: 78-kV, 50-MVA transformer of Problem 2.15 connected as an autotransformer. a. Determine the voltage ratings of the high- and low-voltage windings for this connection and the kVA rating of the autotransformer connection. b. Calculate the efficiency of the transformer in this connection […]

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Consider a 460-V, 25-kW, four-pole, 60-Hz induction motor which

Consider a 460-V, 25-kW, four-pole, 60-Hz induction motor which Consider a 460-V, 25-kW, four-pole, 60-Hz induction motor which has the following equivalent-circuit parameters in ohms per phase referred to the stator: R1 = 0.103 R2 = 0.225 X1 = 1.10 X2 = 1.13 Xm = 59.4. The motor is to be operated from a variable […]

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Consider a three-phase 6/8 VRM.

Consider a three-phase 6/8 VRM. Consider a three-phase 6/8 VRM. The stator phases are excited sequentially, requiting a total time of 15 msec. Find the angular velocity of the rotor in r/min. Is this the question you were looking for? If so, place your order here to get started!

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