QUESTIONS FROM PREVIOUS QUESTION PAPERS

1. Explain the proportional plus integral control for load frequency control for a single area system.

    

2. With a neat block diagram explain the load frequency control with economic dispatch control.
3. 1. With a neat block diagram explain the load frequency control for a single – area system.
   2. Two generators rated 250MW and 500 MW are operating in parallel The droop characteristics are 4 percent and 6 percent respectively. Assuming that the generators are operating at 50 Hz at no load, how would a load of 750MW be shared? What is the system frequency? Assume free governor action.
4. 1. Explain the load frequency control problem in a multi-area power system.
5. 1. Draw the block diagram representation of load frequency control.
   2. For two-area load frequency control with integral controller blocks, derive an expression for steady values of change in frequency and tie-line power for simultaneously applied unit step load distrurbance inputs in the two areas.
6. Draw the block diagram of a power system showing the governor, turbine and syngenerator indicating their transfer functions for a step disturbance of small change P_D. Obtain the response of increment in frequency, making suitable assumptions
   1. without proportional plus integral controller, and
   2. with proportional plus integral control.