M.Tech Degree Examination

(Pages: 3) Reg. No……………

Name………………

M.TECH DEGREE EXAMINATION Model Question Paper First semester Branch: Electrical and Electronics Engineering; Specialization: Power Systems

MEEPS 103 COMPUTER APPLICATIONS IN POWER SYSTEM

(2013 admission onwards) [Regular/ Supplementary] Answer all questions Time: Three hours Maximum: 100 marks

1. (a) What is meant by primitive network? (5 marks)

(b) Explain development of network matrices from graph theoretic approach. (15 marks)

2. (a) Form the bus impedance matrix Zbus by building algorithm for the following power system network whose parameters (ie per unit impedances) are given below. (b)Modify

the Zbus matrix thus obtained to include the addition of an element 2-5 with an impedance

of 0.4.(c) Modify the original Zbus matrix of part (a) when element 3-4 is removed.

(d)Modify Zbus if element 1-2 mutually coupled to the element 1-5 is deleted. (25 marks)

1 2 1 2 3 Turn over 2

Element Self impedance Mutual impedance No. Bus No. Impedance Bus No. Impedance p-q Zpq-pq m-n Zpq-mn pu 1 1-2 0.5 1-5 0.1 2 2-3 0.5 2-4 0.2 3 3-4 0.25 4 2-4 0.6 4-5 0.2 5 4-5 0.75 6 1-5 0.4

3. For the power system shown in figure, use Gauss Siedel method to determine bus voltage V2 and V3 with initial estimates of 1.0+j0pu.Perform two iterations. Also find line flows, line losses and slack bus real and reactive powers. Line impedances are in pu on a100 MVA base

(25 marks)

320 MVAR

4. (a). Explain with algorithm and flowchart Newton Raphson method of Load flow(15 marks)

(b). Discuss any one scheme for optimal ordering in sparsity techniques. (10 marks) 5. Explain the representation of the following power systems components

(i) Synchronous machine

(ii) Transmission system (25 marks) (iii) Three phase power system network

Turn over 6. (a). Explain tap changing and Phase shifting in transformers.

(b). Explain the incorporation of following devices in load flow calculations.

(i) SVC (25 marks) (ii) TCSC

7. For the network shown in figure, perform short circuit studies and determine bus voltage after the fault, line flow and fault level for (a)Three phase to ground fault and (b) Single phase to ground fault at bus 5.(Assume direct short circuit)

2 3 2 3 4

Element Number Bus Code p-q Self impedance Zpq0,1,2 pu 1 1-2 0.05 0.20 0.20 2 2-3 0.05 0.15 0.15 3 3-4 0.06 0.25 0.25 4 4-5 1.02 0.50 0.50. 5 3-5 1.50 0.80 0.80 6 1-5 2.50 1.50 1.50 (25 marks) OR

8. Explain algorithms for calculating system conditions after the occurrence of faults (25 marks) [4×25 =100 marks]