Fault Analysis helps in exploring the faults that occur in the power networks. Which provides useful data for protection settings and stability expectations. There are various types of faults in the power transmission line that can occur however, four main types of faults occur more often as follows: Single line to ground Line to line Three-phase to the ground (balanced) Line to line to ground
Figure 1 - Types of faults in power network [1]
The figure above shows the types of faults, and the most common fault is a Single line to the ground which occurs approximately 75% of the time and a three-phase balanced fault occurs least likely approximately 5% of the time.
Assumptions are also made to simplify the fault analysis:
At the time fault, the system is operating at no load which means there is no load current so pre-fault currents before the fault are zero.
All emf of the generators in the system are operating per unit. Which is
Shunt component elements are ignored
Transient effects are neglected
The purpose of this assignment is to analyze fault in a network where each phase, currents and the phase voltages are effected. The system will be designed in this experiment for solving symmeterical and asymetrical faults at where the faults are occured. The ditribustion system is provided as shown in figure 2 along with a sequence reactances on a 100 MVA base in Table 1 and volatge levels throughout the system shown in KV in Table 2. In the example below fault is occured at bus 3.
