52109-mt----power System Operation & Control

NR

Code No: 52109/MT M.Tech. – I Semester Supplementary Examinations, September, 2008 POWER SYSTEM OPERATION & CONTROL (Power System Control & Automation) Time: 3hours

Max. Marks:60 Answer any FIVE questions All questions carry equal marks ---

1.a) b)

Briefly discuss about different techniques for the solution of unit commitment. Explain the priority list scheme unit commitment method.

2.a) b)

What are the advantages of DP method over priority list scheme? With the help of a flowchart, explain the DP programming solution procedure for the unit commitment problem.

3.a) b) c)

Derive block diagram representation of uncontrolled single area. Explain the concept of control area System data for an uncontrolled single area is follows Rated area capacity = 200mw Normal operating load = 1000 mw Inertia constant = H = 5 sec Regulation IR = 2.4 Hz/mw(p.u) System frequency = 50Hz Find steady state error in frequency following a step increase of load 40 mw. Assume load and frequency are linearly related.

4.a)

Explain the combined operation of LFC and economic dispatch control system. Comment on PI control system employed in LFC operation.

b)

Contd….2

Code No: 52109/MT

5.a) b)

::2::

NR

Develop block diagram representation for two area LFC system with controlled mode and explain each unit Consider the two area system connected by a tie line with the following characteristics. Area 1: Area 2:

R(p.u) 0.01 0.02

D(p.u) Base MVA 0.8 500 1.0 500

Where R is the speed regulation and D represents change in load due to change in frequency. A step change of load is 100 mw occurs in area-1. What is the new steady state frequency and change in tie line power flow? Assume both areas were at nominal frequency (50 Hz) to begin. 6.a) b)

Obtain a dynamic steady state variable model by considering a controlled two area system. Draw the dynamic characteristics of two area Lfc and comment on its.

7.a) b)

Explain the procedure for obtaining composite cost curve. Discuss about the fuel scheduling by linear programming.

8.a) b)

What is meant by multiple interchange contacts. Explain the centralized economic dispatch of a power pool.

^*^*^