Consider the plunger actuator of figure. Assume that the plunger Consider the plunger actuator of figure. Assume that the plunger is initially fully opened (g = 2.25 cm) and that a battery is used to supply a current of 2.5 A to the winding. a. If the plunger is constrained to move very slowly (i.e., […]
Consider a 500-kW, 2300-V, 50-Hz, eight-pole synchronous motor w Consider a 500-kW, 2300-V, 50-Hz, eight-pole synchronous motor with a synchronous reactance of 1.18 per unit and AFNL = 94 A. It is to be operated under field-oriented torque control using the unity-power-factor algorithm described in the text following Example 11.8. It will be used to […]
A salient-pole synchronous generator with saturated Xd = 1.57 A salient-pole synchronous generator with saturated synchronous reactances Xd = 1.57 per unit and Xq = 1.34 per unit is connected to an infinite bus of rated voltage through an external impedance X bus = 0.11 per unit. The generator is supplying its rated MVA at […]
b. Calculate the no-load rotational loss. c. The motor is suppli b. Calculate the no-load rotational loss. c. The motor is supplied from a 30-V dc supply through a PWM inverter. Table gives the measured motor current as a function of the PWM duty cycle D. Complete the table by calculating the motor speed and […]
A dc-motor shunt field winding of resistance 210Ω is to be A dc-motor shunt field winding of resistance 210東 is to be supplied from a 220-V rms, 50-Hz, three-phase source through a three-phase, phase controlled rectifier. Calculate the delay angle 杰d which will result in a field current of 1.1 A.
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 […]
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) = […]
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 […]
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 […]
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 […]