QUESTIONS FROM PREVIOUS QUESTION PAPERS

1. Explain in detail the terms production costs, total efficiency, incremental efficiency and incremental rates with respect to a thermal power plant.
2. 1. What is an incremental fuel cost? Howis it used in thermal plant operation?
   2. Name the components of production cost and explain.
3. 1. Describe in detail, with suitable examples, the methods of optimum scheduling of generation of power from a thermal station.
   2. What is production cost of power generated and incremental fuel rate?
   3. Write the expression for hourly loss of economy resulting from error in incremental cost representation.
4. 1. Explain how the incremental production cost of a thermal power station can be determined.
   2. Explain the various factors to be considered in allocating power generation to different power stations for optimum operation.
5. 1. Explain the following terms with reference to power plants: heat input – power output curve, heat rate input, incremental input, generation cost and production cost.
   2. What are the methods of scheduling power generation of steam plants? Explain their merits and demerits?
6. Describe the need for co-ordination of different power stations.

    

7. What is the objective in economic load scheduling.

    

8. Explain the significance of equality and inequality constraints in the economic allocation of generation among different plants in a system.

    

9. A power system consists of two, 125 MW units whose input cost data are represented by the equations.

    

   C₁ = 0.04 P₁² + 22 P₁ + 800 Rs/hr
   C₂ = 0.45 P₂² + 15 P₂ + 1000 Rs/hr

    

   If the total received power P_R = 200 MW. Determine the load division between the units for most economic operations.

    

10. The incremental fuel costs for the two plants are given by
    

    Where F is in Rs/hr and ‘P’ is in MW. If both units operate at all times and maximum and minimum loads on each are 100 MW and 20 MW respectively, determine the economic load schedule of the plants for the loads of 80 MW and 180 MW. Neglect the line losses.

     

11. The incremental fuel inputs for a two unit stam plant are given by
    

    Find the loss in economy if the two units share a load of 300MW equally instead of operating in an optimum way.