unsymmetrical fault stuy

Question 1

any abnormal condition
of the system that involves the electrical failure of the equipment, such as ,
transformers, generators, busbars, etc.

Answer 1

fault

Question 2

These faults occur due to the failure of one or more conductors.
The most common causes of these faults include joint failures of
cables and overhead lines, and failure of one or more phase of
circuit breaker and also due to melting of a fuse or conductor in
one or more phases.

Answer 2

1.OPEN CIRCUIT FAULTS (also called as Series Faults)

Question 3

It can be defined as an abnormal connection of very low of
impedance between two points of differential potential, whether
made intentionally or accidentally.

Answer 3

SHORT CIRCUIT FAULTS (also called as Shunt Faults)

Question 4

is also called a balanced fault. This fault
occurs when all three phases are simultaneously short-circuited.

Answer 4

Symmetrical Faults

Question 5

The most common faults that occur in the power system network

Answer 5

UNSYMMETRICAL FAULT

Question 6

one of the most common faults,This forms a short circuit path
between the line and ground. These are very less severe
faults compared to other faults.

Answer 6

Single-Line-to-Ground Fault-

Question 7

occurs when a live
conductor gets into contact with another live conductor.

Answer 7

Line-to-Line Fault

Question 8

two lines come into contact with each other as well as
with the ground.

Answer 8

Double-Line-to-Ground Fault

Question 9

are generated
by interconnecting the sequence networks for each of
the components.

Answer 9

SEQUENCE NETWORK

Question 10

For a given power system shows all the paths for the flow of positive
sequence currents in the system. It is represented by one-line
diagram and is composed of impedances offered to the positive
sequence currents.

Answer 10

POSITIVE SEQUENCE NETWORK

Question 11

For a given power system shows all the paths for the flow of
negative sequence currents in the system. It is also represented by
one-line diagram and is composed of impedances offered to the
negative sequence currents.

Answer 11

NEGATIVE SEQUENCE NETWORK

Question 12

For a given power system shows all the paths for the flow of zero
sequence currents. The zero sequence network of a system depends
upon the nature of connections of the 3-phase windings of the
components in the system.

Answer 12

ZERO SEQUENCE NETWORK

Question 13

is an essential tool for the determination of short-circuit
currents that result from different fault phenomena, the estimation of
fault locations, the identification of under-rated equipment in electric
power systems and the sizing of various system components.

Answer 13

Fault analysis

Question 14

PROTECTION DEVICES AGAINST FAULTS

Answer 14

FUSE

CIRCUIT BREAKER

PROTECTIVE RELAYS