To minimize a high over voltage at the open end of a transmission line, which type of load is recommended?

To minimize high overvoltage at the open end of a transmission line, the most effective type of load is a lagging power factor load. When a transmission line is energized but has no load at the receiving end, it can result in a phenomenon known as Ferranti effect, which leads to an increase in voltage (overvoltage) due to the capacitance of the line. A lagging power factor load, typically an inductive load, such as motors or transformers, helps in countering the effects of this capacitance by drawing reactive power from the line, which in turn reduces the overall voltage levels.

This helps to stabilize the voltage along the line and prevent it from rising to levels that could cause insulation failures or disrupt system operations. Therefore, by introducing a lagging power factor load to the system, the dynamic response to voltage fluctuations is improved, effectively mitigating the overvoltage condition caused by a lack of load at the transmission line’s open end.