MEEPE201 Solid State DC & AC Drives M.Tech Model Question Paper : mgu.ac.in
Name of the University : Mahatma Gandhi University
Department : Electrical and Electronics Engineering
Degree : M.Tech
Subject Code/Name : MEEPE 201/Solid State Dc And Ac Drives
Sem : II
Website : mgu.ac.in
Document Type : Model Question Paper
Download Model/Sample Question Paper :
Set I : https://www.pdfquestion.in/uploads/mgu.ac.in/5284-1-MEEPE%20201%20Solid%20State%20DC%20and%20AC%20Drives%20-set1.doc
Set II : https://www.pdfquestion.in/uploads/mgu.ac.in/5284-2-MEEPE%20201%20Solid%20State%20DC%20and%20AC%20Drives%20-set2.doc
Solid State DC & AC Drives :
M.TECH. Degree Examination :
Branch : Electrical and Electronics Engineering
Specialization – Power Electronics
Related : MGU MEEPE204 Modeling & Analysis of Electrical Machines M.Tech Model Question Paper : www.pdfquestion.in/5288.html
Model Question Paper – I :
Second Semester :
MEEPE 201 Solid State Dc And Ac Drives :
(Regular – 2011Admission onwards)
Time: Three hours
Max. Marks: 100
(Answer all Questions)
1. (a) Explain the motor performance parameters and input supply performance parameters of Single Phase DC Drives ( 10 Marks )
(b) The speed of a10 hp, 230V, 1200 rpm separately excited dc motor is controlled by a single phase full converter. The rated motor armature current is 38A and the armature resistance is 0.3?.
The ac supply voltage is 260V.The motor voltage constant is Ka F =0.182V/rpm. Assume that sufficient inductance is present in the armature circuit to make the motor current continuous and ripple free.
Rectifier Operation(Motoring Action) For a firing angle a =300 and rated motor current calculate
(i) The motor torque
(ii) The speed of the motor
(iii) The supply power factor
Inverter Operation(Regenerating Action) The polarity of the motor back emf Eb is reversed by reversing the field excitation. Calculate (i)The firing angle to keep the motor current at its rated value.
(ii)The power fed back to the supply (15 Marks)
OR
2 (a) Explain the working of a single phase semi converter fed dc drive with wave forms and basic equations (15 Marks)
(b) Explain the semi converter operation of full converters for power factor improvement (10 Marks)
3 (a) Explain the working of Three Phase semi converter fed dc drive (10 Marks)
(b)A 80kW, 440V, 800 rpm dc motor is operating at 600 rpm and developing 75% rated torque is controlled by 3-F,six pulse thyristor converter.If the back emf at rated speed is410V, determine the triggering angle of the converter. The input to the converter is 3-F,415V,50Hz ac supply (15 Marks)
OR
4 (a) Explain the working of a Three Phase full converter fed dc drive. Draw the waveforms for a = 600and a = 900 (10Marks)
(b) Explain the non-circulating current and circulating current mode of operation of Three phase Dual converters (15Marks)
5 (a) What are the advantages of chopper fed drives (5 Marks)
(b) Explain the operation of a single quadrant chopper fed separately excited dc motor drive (10 Marks)
(c) The speed of a separately excited dc motor is controlled by a chopper. The dc supply Voltage is 120V, armature circuit resistance is 0.5?, armature circuit inductance is 20mH and motor constant is Ka F = 0.05V/rpm.The motor drives a constant torque load Requiring an average armature current of 20A.
Assume that motor current is continuous.
Determine (a) The range of speed control (b) The range of duty cycle a (10 Marks)
OR
6 (a) What are the different chopper configurations?. Explain. ( 15 Marks)
(b) Explain the principle of multiphase choppers (10 Marks)
7 (a) Explain the rotor resistance control schemes for induction motors (10 Marks)
(b) Explain the different slip power recovery schemes for induction motor control (15 Marks)
OR
8 (a) Explain the stator voltage control schemes for speed control of induction motors(10 Marks).
(b) Explain the principle of vector control of induction motors (15 Marks)
M.Tech. Degree Examination :
Branch : Electrical and Electronics Engineering
Specialization – Power Electronics :
Model Question Paper – II :
Second Semester
MEEPE 201 Solid State Dc And Ac Drives (Regular – 2011Admission onwards)
Time : Three hours
Max. Marks: 100
Answer all Questions :
1 (a) Explain the different power factor improvement methods in single phase converters (10 Marks)
(b) A separately excited dc motor is fed from a 230V, 50Hz supply through a single phase half controlled bridge rectifier.The armature inductance is 0.06H and armature resistance is 0.3Ω ,the motor voltage constant is Ka = 0.9 V/A rad/s and the field resistance is 104Ω.
The field current is also controlled by a semi converter and is set to maximum possible value.The load torque is TL= 50N-m at 800 rpm.The inductances of the armature and field circuits are sufficient enough to make the armature and field currents continuous and ripple free.
Calculate
(i) The field current If
(ii) The firing angle of the converter in the armature circuit and
(iii) the input power factor of the armature circuit converter.Neglect the system losses ( 15 Marks)