Page 2 of 2. POWER QUALITY, ELECTROMAGNETIC COMPATIBILITY AND RELIABILITY.pdf. POWER QUALITY, ELECTROMAGNETIC COMPATIBIL
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*EJM054*
III Semester M.E. (Power and Energy Systems) Degree Examination, January 2013 (2K8 Scheme) PSEL-34 : POWER QUALITY, ELECTROMAGNETIC COMPATIBILITY AND RELIABILITY Time : 3 Hours
Max. Marks : 100
Instruction : Answer any five full questions. 1. a) How are power quality problems evaluated ?
10
b) Discuss long term voltage variations which cause PQ problems.
10
2. a) Define active power, reactive power, apparent power, power factor and displacement power factor under non-sinusoidal conditions.
10
b) Discuss the CBMA and IITC curves used to define PQ acceptability. What is the significance of these curves ?
10
3. a) Why do harmonics occur ? What is the effect of harmonics on equipment ? b) Briefly discuss how harmonics can be reduced.
10 10
4. a) Describe the process of bench marking. Why is it necessary ?
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b) Explain the function and purpose of harmonic analyzers and spectrum analyzers.
10
5. a) PQ data is voluminous. Discuss how this data can be assessed ?
10
b) How can expert systems be used in PQ monitoring ? What are the key features of expert system development ?
10
6. a) Briefly discuss the transducers available for PQ monitoring. What dictates the choice of transducers ?
10
b) Why do flickers occur ? How are they different from notches ? How can they be measured ?
10 P.T.O.
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7. a) Briefly discuss the indices used to quantify harmonics. Compare the merit of the indices.
10
b) What are the transient types which occur ? What are the causes for transients ?
10
8. a) How is power system adequacy assessed at different hierarchical levels ?
10
b) Discuss the indices used to quantify reliability at the HLI (Generation) level. 10 _______________________