1. Explain demand side management and contingency analysis for a power system.

2. Write down an algorithm for the formation of Z bus matrix using four types of modification techniques.

3. A constant load of 300 MW is supplied by two 200 MW generators, 1 and for which the respective incremental fuel costs are

dC1/dPG1 =0·10 PG1 20.0
dC2/dPG2 =0·12 PG2 15.0

with powers PG in MW and costs C in Rs/hr. Determine

the most economical division of load between the generators

the saving in Rs/day thereby obtained compared to equal load sharing between machines.

4. For the system whose one line diagram is shown in the figure assume I1 1 L0° per unit and I2 =0·8 L0° per unit. If the voltage at bus 3 is V3 1 L0° per unit, find the loss coefficients. Line impedances are (0.04 0.16) per unit, (0.03 0·12) per unit and (0.02 0.08) per unit for sections respectively,

<img src='./qimages/15581-4.jpg'>

5. Write down the principle of operation of autotransformers and derive the formula for percentage copper saving in comparison to the winding transformers.

6. For the 3-bus network shown below, find the bus admittance matrix.

<img src='./qimages/15581-6.jpg'>

7. Enumerate the different types of load flow methods and explain bus mismatch and convergence criteria.

8. Write short notes on any two of the following:

Electric supply industry structure under deregulation

Economical load scheduling of hydrothermal plants

Concepts of decoupled methods