Answer :
Final answer:
The part of complex power that can be controlled is the reactive power.
Explanation:
When two transmission lines are connected in parallel and a buck-boost transformer is connected to one of the lines, the part of complex power that can be controlled is the reactive power.
Complex power is made up of two components: real power, which is the power that is consumed or supplied to the electrical load; and reactive power, which is the power that is exchanged between the lines or stored in the electrical components. By adjusting the buck-boost transformer, the reactive power can be controlled, leading to a more balanced distribution of power and improving the overall efficiency of the system.
For example, if the system has a high amount of reactive power, the buck-boost transformer can be adjusted to reduce it, resulting in reduced line losses and voltage drops.
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