Industrial Drives and Applications Important Questions


  1. With a neat block diagram, state the essential parts of an electric drive system. Explain them briefly.
  2.  What are the advantages of an electric drive system?
  3.  With the help of the quadrantal diagram, explain the four-quadrant operation of a motor, drive a hoist load.
  4.  Derive an expression for the equivalent load torque and equivalent moment of inertia for loads with translational and rotational motion.
  5.  Explain the methods to measure the moment of inertia.
  6.  Explain the different classifications of load torque and also define active load torque and passive load torque for example.
  7.  Derive an expression to calculate the time and energy loss in transient operations.
  8.  Explain the steady-state stability and derive the condition for steady-state stability.
  9.  Derive an expression for moment of inertia of flywheel used in load equalization.
  10. With neat diagram explains various components of load torque.
  11.  What are the factors responsible for the selection of motors?
  12.  With usual notation, derive the expression for a temperature rise of a machine. Sketch the temperature riseversus the time curve.
  13.  Determine the expression of over-loading facto ‘K’ while selecting the motor rating, for a short time duty class.
  14.  Determine the expression of over-loading factor ‘K’ while selecting the motor rating, for intermittent period duty class.
  15.  Explain the classification of duty for motors with load diagrams. With a neat graph explain briefly and give examples in each case.
  16.  Develop an expression to determine the power rating of an electric motor using the method of equivalent current for variable load conditions.
  17.  Determine the expression for a maximum number of switching frequency of a drive system.
  18.  With a neat circuit and graph, explain the regenerative, dynamic, and plugging type of braking system for separately excited DC shunt motor.
  19.  Discuss the various methods of speed control of DC motor.20. Explain the operation of a single-phase half-controlled rectifier control of separately excited DC motor.
  20.  Explain the operation of a single-phase fully controlled rectifier control of separately excited DC motor.
  21. Explain with diagram three phase fully-controlled rectifier control of d.c. separately excited motor.
  22. With neat circuit diagrams explain the multi quadrant operations of DC separately excited motor.
  23. With neat circuits and waveforms for continuous conduction, explain the working of DC series motor fed from single phase half controlled rectifier.
  24. Explain the operation of a chopper control of separately excited DC motor and DC series motor.
  25. Explain the chopper control of separately excited DC motor for regenerative braking and dynamic braking.
  26. Explain the operation of variable frequency control from voltage sources
  27. Explain the operation of VSI fed induction motor drives.
  28. Explain any three methods of braking of an induction motor.
  29.  Explain the static scherbius drive system.
  30. Explain clearly the driving motors used in the cement industry for different operations.
  31.  With a neat sketch, explain the paper mill drive system.