Soln unit5
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The document describes the transfer reactances between a generator and infinite bus bar under various conditions, including pre-fault, during fault, and post-fault. It then asks to determine the maximum load that can be transferred without loss of stability if the fault is cleared when the rotor has advanced 600 electrical degrees from its prefault position. Through calculations using the reactance values and rotor position, it determines the maximum load is 127.3 MW.
![1. The transfer reactances between a generator and an infinite bus bar operating at
200KV under various conditions on the interconnector are:
Prefault: 150ohm per phase
During Fault: 400ohm/phase
Post Fault: 200ohm/phase
If the fault is cleared when the rotor has advanced 600 electrical from its prefault
position, determine the maximum load that could be transferred without loss of
stability. [127.3MW]
It is nowhere mentioned that the generator is supplying any load and hence we
have to assume that the voltage is same as that of the infinite bus(=200KV),
although I have taken it as E and at the end substituted the same.
A1 = A2
Integrate to get the above areas and apply the limits as shown in the figure above.
Pe1 = 1.33Esin(del)
Pe2 = 0.5Esin(del)
Pe3 = Esin(del)
A1 = 0.957Esin(del0) – 0.25Ecos(del0)
A2 = E(cos(del0 + 600) – cos(pi – del1)) – 1.33E (sin del0)(pi – del1 - del0 - 60)*pi/180
And P = Esin del1 = 1.33sin(del0)
So we get a relation between the 2 deltas
Assume del0 initial value (intelligent guess is < 30 as the increase is 60 and 60+30
should be less than 90 in most of the cases )
After 2 or three 3 trials u will get del0 = 280; del1 = 38.630
P = Pe3 at del1
Hence P = 200*200/200sin(del1) = 125MW](https://image.slidesharecdn.com/solnunit5-100506005626-phpapp02/85/Soln-unit5-1-320.jpg)
Soln unit5
- 1. 1. The transfer reactances between a generator and an infinite bus bar operating at 200KV under various conditions on the interconnector are: Prefault: 150ohm per phase During Fault: 400ohm/phase Post Fault: 200ohm/phase If the fault is cleared when the rotor has advanced 600 electrical from its prefault position, determine the maximum load that could be transferred without loss of stability. [127.3MW] It is nowhere mentioned that the generator is supplying any load and hence we have to assume that the voltage is same as that of the infinite bus(=200KV), although I have taken it as E and at the end substituted the same. A1 = A2 Integrate to get the above areas and apply the limits as shown in the figure above. Pe1 = 1.33Esin(del) Pe2 = 0.5Esin(del) Pe3 = Esin(del) A1 = 0.957Esin(del0) – 0.25Ecos(del0) A2 = E(cos(del0 + 600) – cos(pi – del1)) – 1.33E (sin del0)(pi – del1 - del0 - 60)*pi/180 And P = Esin del1 = 1.33sin(del0) So we get a relation between the 2 deltas Assume del0 initial value (intelligent guess is < 30 as the increase is 60 and 60+30 should be less than 90 in most of the cases ) After 2 or three 3 trials u will get del0 = 280; del1 = 38.630 P = Pe3 at del1 Hence P = 200*200/200sin(del1) = 125MW