How should a system operator handle a transmission line that is experiencing loading above the operating limit?

Placing the capacitor bank online at Station A is a proactive step to manage a transmission line that is experiencing loading above its operating limit. By doing so, the system operator can improve the voltage stability and support the overall voltage levels on the line. Capacitor banks provide reactive power support, which can help alleviate some of the loading by reducing the demand for reactive power from the transmission line, thereby enhancing its capacity to carry active power without exceeding its limits.

When a transmission line is loaded beyond its capabilities, managing the reactive power flow is essential, and engaging the capacitor bank can help stabilize the system and potentially reduce the current flowing through the line by adjusting voltage levels. This action can ultimately delay or prevent the need for more drastic measures, such as line disconnection, which could impact system reliability and service provision.

The other choices may not effectively address the issue. Increasing the voltage could worsen the situation if the line is already overloaded. Reducing the current flow could require altering power generation or load demands, which is often less immediate and practical. Disconnecting the line is a drastic measure that may lead to service interruptions, making it less favorable unless absolutely necessary for system safety. Thus, engaging the capacitor bank is a more optimal and efficient first response to managing transmission