what use can we make of 3rd harmonic component

Answer Posted / ketul

Yy connection without neutral wires with both primary and
secondary connected in
star no closed path exists. As the triplen harmonics are
always in phase, by virtue
of the Y connection they get canceled in the line voltages.
Non-triplen harmonics
like fundamental, become rt3 times phase value and appear
in the line voltages. Line
currents remain sinusoidal except for non-triplen harmonic
currents. Flux wave in each
transformer will be flat topped and the phase voltages
remain peaked. The potential
of the neutral is no longer steady. The star point
oscillates due to the third harmonic
voltages. This is termed as ”oscillating neutral”.

Yy connection with neutral wires When a neutral wire is
provided the triplen har-
monic current can flow and the condition is similar to the
single phase case (with a star connected 4 wire source or
with the system earth).The neutral wire carries three
times the triplen harmonic current of one transformer as
these currents are co-phasal.
Unloaded secondary neutral will not be operative. In a Yy
connection, to obtain third harmonic suppression one may
provide a third
winding which is connected in mesh, which can be an
unloaded winding. It is called a
tertiary. This winding improves the single phase to earth
fault detection also. Further,
this winding can be used to feed some permanent station
loads also. Such transform-
ers are designated as Yyd transformers. If the neutral
wires are provided and also
mesh connected winding is present, then triplen harmonics
are ’shared’ between them
depending upon their impedances.

Is This Answer Correct ?    7 Yes 6 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is magneto on a gas generator. how it functions. its out put is d.c or a.c. how it can be checked for correct functioning

1418


What is a differential amplifier? Also, explain cmrr.

688


difference between high and low impedance BUS BAR relay??

1071


Is electro plating what type of load whether resistive, inductive or capacitive loads

2903


what is the advantage of connecting capacitors in delta than in star?

1632






Logic using 1 kV or 1,1 kV grade in house wiring Low voltage cable. Explain/suggest? some use 1kV and some prefer 1.1kV grade insulation low voltage cable why??

1213


How Can you do Maintenance of ACB of 2000Amperes

1642


What is size 00, 01, 1 etc., in HRC fuse types?

1843


WHAT HAPPENED DC SERIES MOTOR FIELD WINDING OPEN. CAN POSSIBLE.

3204


Can we check ELCB constantly from R1 to R8 phase in 1 no DB?

1226


Why the standard of ambient teperature mentioned as 40 degree celcius in machines.

1455


how to calculate short circuit current for the busbar

949


STATE USE OF ARC RUNNERS & SPLITTERS ?

1460


I want to ask that is there any relation between current denesity of copper and material purity. also is ther any standard which defines the standard current denesity of material.

1471


what is the relation between reactive power and power factor for the what is the limit of reactive power and power factor

1656