(a) Describe the types of rotors and their functions used in three phase induction motors. (b)...

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(a) Describe the types of rotors and their functions used in three phase induction motors. (b) (c) Three-phase induction motor is wound for 4 poles and is supplied from 50 Hz system. Calculate: (1) (ii) (iii) (0) (ii) (iii) (iv) (v) The synchronous speed. The rotor speed when the slip is 4%, and The rotor speed frequency when rotor runs at 600 r.p.m. (0) (ii) (iii) (iv) (v) (6 marks) The rotor of a 6-pole, 50 Hz induction motor is rotated by some means at 1000 RPM. Determine: Rotor voltage Rotor frequency Rotor slip Torque developed, and Can the rotor rotate at this speed by itself? (5 marks) (6 marks) (d) A 4-pole, 3 phase, 415 V, 50Hz induction motor has the following parameters of its circuit model: Rs = 1.2 02, jXs =j1.16 0 Rr = 0.4 02, jxr =j1.16 0, jXm = 350, Rotational losses are 800 W Given the speed of the motor is 1440 RPM, determine the following: The input current, The power factor, The mechanical power, The output torque, and Its efficiency. (a) Describe the types of rotors and their functions used in three phase induction motors. (b) (c) Three-phase induction motor is wound for 4 poles and is supplied from 50 Hz system. Calculate: (1) (ii) (iii) (0) (ii) (iii) (iv) (v) The synchronous speed. The rotor speed when the slip is 4%, and The rotor speed frequency when rotor runs at 600 r.p.m. (0) (ii) (iii) (iv) (v) (6 marks) The rotor of a 6-pole, 50 Hz induction motor is rotated by some means at 1000 RPM. Determine: Rotor voltage Rotor frequency Rotor slip Torque developed, and Can the rotor rotate at this speed by itself? (5 marks) (6 marks) (d) A 4-pole, 3 phase, 415 V, 50Hz induction motor has the following parameters of its circuit model: Rs = 1.2 02, jXs =j1.16 0 Rr = 0.4 02, jxr =j1.16 0, jXm = 350, Rotational losses are 800 W Given the speed of the motor is 1440 RPM, determine the following: The input current, The power factor, The mechanical power, The output torque, and Its efficiency.