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A star-connected squirrel cage asynchronous motor with 460 Volts (between phases), 60 Hz, 3 poles, rated at 1180 rpm, Rs = 0,2071 22, Rr '= 0,0712, Xs = 0 It has equivalent circuit parameters of, 751, Xr's 0.670 and Rc = 0, Xm = 200. Motor Tload=drives a crane with a constant character. If control is done with v/f technique, a) (5p) If 40 Hz is done, how many V phase voltage will be applied. b) (5p) The nominal torque is how many Nm. c) (20p) When operating at an unknown nx speed, if the frequency is lowered to 40 Hz in order to generate -355 Nm braking torque, what happens as the% t slip at t = 0 +? d) For option 10 (C), calculate the approximate stator current in Ampere at t = 0 +. e) (5p) What will be the motor speed in rpm long enough after the 40 Hz frequency is being applied. Note. 1: All losses not given can be neglected. Note.2: It should be accepted that electrical dynamics develop much faster than mechanical dynamics. A star-connected squirrel cage asynchronous motor with 460 Volts (between phases), 60 Hz, 3 poles, rated at 1180 rpm, Rs = 0,2071 22, Rr '= 0,0712, Xs = 0 It has equivalent circuit parameters of, 751, Xr's 0.670 and Rc = 0, Xm = 200. Motor Tload=drives a crane with a constant character. If control is done with v/f technique, a) (5p) If 40 Hz is done, how many V phase voltage will be applied. b) (5p) The nominal torque is how many Nm. c) (20p) When operating at an unknown nx speed, if the frequency is lowered to 40 Hz in order to generate -355 Nm braking torque, what happens as the% t slip at t = 0 +? d) For option 10 (C), calculate the approximate stator current in Ampere at t = 0 +. e) (5p) What will be the motor speed in rpm long enough after the 40 Hz frequency is being applied. Note. 1: All losses not given can be neglected. Note.2: It should be accepted that electrical dynamics develop much faster than mechanical dynamics