Tiêu đề Industrial Drives Nov 2023.pdf ✅

|Time: 3:00 lours Q.1 ii. (a) 36 A (a) Source (l) (b) Motor(HT) iii. iv. All questions are compulsory. (H V. Vi. Marks are mentioncd on the right s de of cnch qucstion. (3j# 2t va ào qrS 3 3ifod hùt (a) Capacitor Start motor SEM-IV Diploma Exam 2023 (Even) (Ele trical Engincering) (Theory) Int. ustrial Drives (2020405-P) vii. Choose the most suitable ansy rcr the following aptions. Which of the following is uscd to wuild a clcctric drivc? 9A 3r ) (f) Group (A) g4-) (a) Plugging (b) 35 A Calculate the avcragc inductor cu rent of the Boost converter if thc load currcnt is 7A and duty cyclc valuc is 0.8: Which typc of mcthod is known a:.resistancc start motor? Ward-Lconard systcm of system f spccd control is not rçcommended for: (a) constant spccd opcration (b) Wido sjced (a) Split phasc typc What are clcctric drives? ($Gitai^I^A FT?) (a) Engincs of 2-whcclers (b) Laptop: (c) Control unit(-420| yPe) () All of the above(34y4T T) (b) Split plhasc motor (c)34 A Roll No: (c)Two valuc capacitor motor The polarity of back c.m.f changes in which of the method? (c) frequcnt-motor.reverscd (b) Shadcd pole typc (c) Robotics (b) Regenerativc braking (c) Dynamic braking () Capacitor start typc Page 1 of 5 [Max. Marks:70| (d) 31 A The type of single phase induction motor having highest power factor at full load is: 6B189 ECO9ACI75A3C3ABF706D6BEA3A (d) shaded pole motor (d) very slow spccd (1"20-20) (d) Botha &c (d) Rhcostatic braking (d) Capacitor run type (2020405S-P) Way to Polytechnic
BLDC motor is analogous to: (yetsit (a)permanent magnet synchronous motor viii. (b) DC motor ix. (a)angle which a stepper motor has (4F GTU GÌ VF RW HTAgla (b) angle bctwecn the two winding of a stator in a stepper motor (yr cr À (a) change in load (is yka) xi. What is the meaning of step angle of a stepper motor? (c) minimum degree of rotation associated with a single step( yd RUS yu HGH fS) () angle between the stator and rolors (tR ÅR }fodyU) (b) cyclic variation of load torque xiii. (a) Unipolar, Bipolar Which of the not cause of hunting in a synchronous motor ? xiv. (a) 315° fot 3gq È) XV. (c) rotating transformer (qu eieR ) (d) Signal phase induction motor (6) Unipolar, PWM Which of the following are the types of BLDC motor? xii. 4 Electric Vehicles are generally powered by : $to AI6T 34 aR (a) Aluminum batteries (b) Lead-acid batteries (c) Sodium batteries (b) 145° (b) Below the base speed with frequency control (a) Square (a) (c)changes in field current (b) Cube () () change in supply frequency (c) Bipolar, PWM fagt, isay4) Calculate the extinction angle in purely inductive load if the firing angle is r4. (c) 345° Variable frequency (V/f) is maintained constant in the following case of speed control of induction motor: (a)Below base speed with voltage control The output power of the centrifugal pump is proportional to the ÓS`ID d 1 oU) (d) None of these. (c) Square-root (a) Synchronous, Induction Page 2 of 5 Huifd B) (c) Above base speed with frequency control 6B1899EC09AC175A3C3 ABF706D6BEA3A (d)) Magnesium batteries (d) 285° of the specd. (d) Cube-root (ua-4) (2020405-P) Way to Polytechnic
xvi. Reducing the armaturc voltage will give us : (a)Variable torque spced control (b) Constant torquc spccd control xvii. (a) 21 A (a) DC motor Calculate the avcrage valuc of the currcnt through the thyristor in case of 1-0 Full wave bridye rectifiet if the valuc of the load current is 42 A. (b) 12 A xvii. Which type of drive can be used for textile industry? (a) Motoring mode (icts) (b) Regenerative braking mode giafb s) (a) 40 Hz (c) Variable and constant both can be achieved XiX. Type-A chopper is used for obtaining which type of mode? Q.3 (d) Cannot comment on torquc (b) Squirrcl cage induction motor (c) Cumulative compound motor (a) Synchronous molor (c) 14 A (b) 20 Hz Q.2 Explain necd of electric drive. XX. Calculate the output frequency for the two-pulse converter if the supply frequency is 20 Hz. (c) Reverse motoring mode (d) Reverse regenerative braking mode (c) 60 H2 Group (B) (qY -<) OR (3I) (d) 16 A Campare between half wave converter and full wave convertèr ,in single phase SCR drives. A 230V,870 rpm, 10A separately cxcited DC motor has an armature resistance of 0.05 ohm.It is coupled to an ovcrhauling load with a torque of 400 N-m.Find the speed at which the motor can hold the load by regenerative braking. OR (H;a) (a) 9Ó H (y 230V,870 rpm, 10A HCT # 3G DC ACR o| 3TR yfaTro.05 34I SÀ 400N-m o Page 3 of 5 Write the advantages and limitations of stator voltage control for speed control. 6B1899ECO9ACI75A3C3ABF706D6BEA3A 4 (2020405-P)
Q.4 Write about types of DC Motor. OR (3aT) A 6-pole induction motor is fed from 50 HZ supply. If the frequency of rotor emf at full load speed is 2HZ. Find the full load speed and _lip. Q.5 Compare between slip ring induction motor and squirrel cage induction motor. Q.8 OR (Y) Write the couses of huntingphenomenÍn in synchronous motor. Q.6 Write about AC drivemaintenance in brief.Also write different types of typesof AC drive maintenänce. oRrr) OR Compare between Brushless DC Motor and Conventional DC Motor. Group (C) g4-) Q.7 Explain about necessity of speed control of DC motor. Write the various method of speed control characteristics of DC serie_ motor. Explain one method in detail. fagiyasft fafa fafuí fafayies fafatfaAdIR HHG^Ü|) OR (3) Explain how variable voltage and variable frequency can be used for speed control of three phase induction motor ? Draw neat sketch. Definc clcctric drive and explain il with block diagram of electric drive. OR (3Y) Explain the working principle of single phase induction motor and write name of an y three type of single phase induction motor. Page 4 of 5 6B1899ECO9AC175A3C3ABF7061D6BEA3A 6 6 6 (2020405-P) 4 4 Way to Polytechnic