Figure below shows a power system where load at bus 5 is fed by generators at bus 1 and bus 4. The generators are rated at 100MVA; 11 KV with subtransient reactance of 25%. The transformers are rated each at 100 MVA, 11/112 KV and have a leakage reactance of 8%. The lines have an inductance of 1 mH/phase/km. Line L1 is 100 km long while lines L2 and L3 are each of 50 km in length. 1- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the value of the base voltage is changed to 10 kV (i.e. new value/old value). 2- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the length of L1 is reduced to 50 km (i.e. new value/old value).
Three-Phase Transformers
Three-segment transformers are a type of transformer used to transform voltages of electrical systems into three ranges. Two type transformers are shell-type transformer and core type transformer. In brief, it could be described because of the exquisite kinds of configurations.
Transformer
Ever since electricity has been created, people have started using it in its entirety. We see many types of Transformers in the neighborhoods. Some are smaller in size and some are very large. They are used according to their requirements. Many of us have seen the electrical transformer but they do not know what work they are engaged in.
Figure below shows a power system where load at bus 5 is fed by generators at bus 1 and bus 4. The generators are rated at 100MVA; 11 KV with subtransient reactance of 25%. The transformers are rated each at 100 MVA, 11/112 KV and have a leakage reactance of 8%. The lines have an inductance of 1 mH/phase/km. Line L1 is 100 km long while lines L2 and L3 are each of 50 km in length.
1- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the value of the base voltage is changed to 10 kV (i.e. new value/old value).
2- For a 3-phase fault at bus 5, the fault current is equal to 2530A. What the value of the change in the fault current if the length of L1 is reduced to 50 km (i.e. new value/old value).
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