HVDC Engineering (E) OCTOBER 2009 Previous Question Papers

MODEL EXAMINATION, OCTOBER 2009

7th SEMESTER, ELECTRICAL & ELECTRONICS ENGINEERING

               HVDC Engineering(E)

Time: 3 hours                                                                                     Maximum Marks: 100

PART – A

Answer all questions

1)What are the different types of DC link configuration?

2)What do you mean by pulse number?

3)Compare individual phase control and equidistant pulse control

4)Explain HVDC system control hierarchy

5)Briefly explain the basic faults that can occur in a converters

6)Explain the principles of surge arrester

7)What is Harmonic distortion factor?

8)Write short note on Dc filters

9)Compare series and parallel MTDC systems

10)Explain the operation of thyristor switched  capacitor

                                                                                                                 ( 10*4 =40 marks )

PART – B.

Answer all questions

11) What are the advantages and disadvantages of DC transmission systems over AC transmission system?

                             Or

12)Sketch Greatz circuit and explain its simplified analysis without overlap

13)a)Explain individual phase control and mention its limitations

  b)Explain how powe control is achieved automatically in HVDC systems

                        or

 14)a)Explain HVDC converter control characteristics

      b)Explain energisation and deenergistion of bridge in a DC link

15)a)explain the causes of overvoltages

      b)explain the reasons for occurrence pf arc back in thyristor valves

                                   or

16)a)Explain commutation failures in converters and protective measures taken

    b)What is misfire in DC link ?explain its effects in DC link.

17)a)Explain corona and radio interference effects in HVDC systems?

b)What are the various types of AC filters used in HVDC system

                            or

18)Explain about the functions of smoothing reactor.Briefly discuss about the different ways for location of smoothing reactor.

19)Explain different types of MTDC systems and its applications

                             Or

20)

a)Explain the operation of thyristor controlled reactor

b)Write  short notes on

          a)Sources of reactive power

          b)Static VAR systems

                                                                               ^{(12 x 5 =60 marks)}