Which of the following scenarios leads to active control of reactive power flow?

Active control of reactive power flow is primarily associated with scenarios involving the management of how demand and generation interact within the grid. When load offcost generation occurs, utilities can adjust the generation resources to match the reactive power needs of the grid more effectively. Off-cost conditions often arise when there is a surplus of generation or the system experiences low demand, leading to the need for strategic adjustments to maintain voltage stability and efficient power flow.

This scenario allows operators to modulate generators to either absorb or supply reactive power as required to maintain system reliability. By controlling the amount of reactive power delivered or absorbed by generators during off-peak periods, utilities enhance the overall voltage profile of the grid and manage the flow of reactive power actively.

In contrast, the other scenarios involve passive measures or do not focus specifically on reactive power management. Importing additional energy generally addresses active power needs rather than reactive power management directly. Decreasing network connectivity typically limits the ability to manage power flows effectively, and limiting transmission expansion does not contribute to enhancing control over reactive power flow due to potential congestion and voltage issues it may introduce in the grid.