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Question
What is vector group? What is meant by DYN11?Why is it needed?
 Question Submitted By :: Sohel_rana0303
I also faced this Question!!     Rank Answer Posted By  
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 1
Vector group means it define the primary & secondary side
connection type of the transformer says D for the delta
connections & Y for the star connections then the 11 stands
for the phase displacements between the primary side &
secondary side.In the sense in a clock while 11 o clock
shows the angle between the small needle & big needle will
be 30 degree, so the phase displacement will be 30 degree.
 
Is This Answer Correct ?    168 Yes 13 No
Charles
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 2
Vector group of a transformer describes the relation between
primary voltage vectors and the secondary voltage vectors

DYN11 means
D - Primary DELTA connection
Y - Secondary STAR connection
N - Neutral Point available in the secondary star connection
11 - 30 degrees lag (11o clock position for better
understanding)
 
Is This Answer Correct ?    104 Yes 26 No
T Eswara Rao
 
 
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 3
Abobe two reply explained correctly "what is vector group".
The answer to the last question "why it is needed" is as
follows:-
By virtue of constrction & terminal connections of the
transformer, a difference between primary vector &
secondery vector occurs. We need to know the same for the
following reasons:-

1)Matching of vector group is required (to avoid
circulating current/ fault ), when 2 transformer need to be
operate parallal on a common bus/system.

2) to provide transformer differential protection correctly.

etc
 
Is This Answer Correct ?    21 Yes 19 No
Bikash Chandra Pal
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 4
Abobe two reply explained correctly "what is vector group".
The answer to the last question "why it is needed" is as
follows:-
By virtue of constrction & terminal connections of the
transformer, a difference between primary vector &
secondery vector occurs. We need to know the same for the
following reasons:-

1)Matching of vector group is required (to avoid
circulating current/ fault ), when 2 transformer need to be
operate parallal on a common bus/system.

2) to provide transformer differential protection correctly.

etc
 
Is This Answer Correct ?    7 Yes 17 No
Ghost Rider
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 5
Abobe two reply explained correctly "what is vector group".
The answer to the last question "why it is needed" is as
follows:-
By virtue of constrction & terminal connections of the
transformer, a phase difference between primary vector &
secondery vector occurs. We need to know the same for the
following reasons:-

1)Matching of vector group is required (to avoid
circulating current/ fault ), when 2 transformer need to be
operate parallal on a common bus/system.

2) to provide transformer differential protection correctly.
 
Is This Answer Correct ?    11 Yes 9 No
Sukhdev Negi
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 6
The Dyn11 is interpreted as follows:
D-primary winding is delta connected (i.e the three primary
phase windings within the transformer)
y-the secondary winding is delta connected

11-is a multiplying factor for the phase displacement
between the primary and secondary voltages
i.e. for the Dyn11, phase displacement is
= 11*30degrees
= 330 degrees
 
Is This Answer Correct ?    10 Yes 29 No
Strateia
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 7
I read a number of answers but nobody has cleared about the
leading and lagging thing. In case of Dyn11, 11 indicates 11
o'clock i.e. a displacement of 30 degrees between HV and LV.
Now in this case, is HV leads LV by 30 degrees or vice
versa and how can one find out that in any of the cases.
 
Is This Answer Correct ?    2 Yes 7 No
Shraddha
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 8
above answers are correct but as u asked shraddha that will
hv lead or lv so i clear that capital D is for secondary and
small forthe primary and again 11 ....means that hv have the
30 degree leading phase diffrence..
 
Is This Answer Correct ?    2 Yes 9 No
Avnish
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 9
Clarification for shraddha:
11o clock means primari voltage vectors leading 30deg
with reference to secondary voltage vectors.OR secondary
voltage vectors lagging 30deg with reference to primary
voltage vectors.

As in a clock at 11o clock big needle leads small
needle by 30deg OR small needle lags big needle by 30deg
 
Is This Answer Correct ?    2 Yes 6 No
T Eswara Rao
 
  Re: What is vector group? What is meant by DYN11?Why is it needed?
Answer
# 10
It means that the LV winding voltage lags the HV winding
voltage by 30 degrees.
The 11 typically means 11 o'clock on a standard clock.
whenever you see a vector group like Dy11 ar Yd1 or Yd5 ...
all you have to do is first FIX THE HV WINDING AT 12 o clock
now the 11 shows that it is behind 12 on the clock so you
can say that the LV is lagging by....30 degrees
in Yd1, the lv windings is at 1 o' clock meaning it is
ahead of 12 o clock by thirty degrees so it means that the
LV winding leads the HV winding voltage by 30 degrees
in Yd5, the lv windings is at 5 o' clock meaning it is
ahead of 12 o clock by 150 degrees so it means that the LV
winding leads the HV winding voltage by 150 degrees
 
Is This Answer Correct ?    16 Yes 7 No
Earnest Paul
 

 
 
 
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