Power Flow. Consider a four-bus power system. Bus 1 is the slack bus. Bus 2 is a voltage controlled bus. Buses 3 and 4 are load buses. There are generators at buses 1 and 2.
Transmission lines connect ail buses directly to each other except there is no direct connection
between buses 1 and 4 and between buses 3 and 4.
a. (10 points) Write a minimum-size set of power flow equations that can be solved
simultaneously. Use appropriate network parameter designations go and b, for buses i and i; P
and Q are the generated real and reactive power at bus i; Vat angle 8, is the bus voltage
magnitude and phase angle at bus i. (Your equations will have few, if any, actual numbers in
them.)
b. (5 points) Identify the unknowns that the minimum-size set of power flow equations will
solve we