Necessity of Reactance for Interconnected Stations
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| Figure A |
- Consider two stations A and B which are being operated in parallel as shown in Figure A. A reactor or an inductance is connected between the busbars of the two systems.
- Let the load over station B be more than what it can supply (generate), so the extra load will fall upto station A. Hence, a power flow will take place from station A to station B.
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| Figure B |
- The vector diagram for phase angle between voltage of station’s bus bars A and B is represented in Figure B. The voltage EB at bus bars of station B has been taken as a reference.
- Let the load current supplied by station A lag from reference vector EB, by an angle Φ. The voltage of station A (EA) will lead from EB and is equal to EB + IX as shown.
- Now consider that the load of station B Increase further, as the governors of the prime movers have drooping characteristics, It will cause the voltage of station B to swing back a little say by an angle equal to αl as the voltage of a bus – bar at station A is fixed it will cause an increased current I1 , to flow from station A to station B, so that (EA– IX) is the new voltage of station Bl as shown in Figure B.
