Full load compensation in a power transmission line is achieved by using shunt capacitors. Shunt capacitors are connected in parallel with the transmission line to compensate for the reactive power and improve the power factor of the system. This helps in reducing the losses and voltage drop in the transmission line.

Shunt capacitors work by supplying reactive power to the system, which counteracts the reactive power consumed by inductive loads. They help in maintaining a balanced power factor by compensating for the lagging reactive power in the system.

The main advantages of using shunt capacitors for full load compensation in a transmission line are:

1. Power Factor Improvement: Shunt capacitors help in improving the power factor of the system by supplying reactive power. This reduces the overall reactive power demand from the power source and improves the efficiency of the system.

2. Voltage Regulation: Shunt capacitors help in reducing the voltage drop in the transmission line by compensating for the reactive power. This ensures that the voltage at the load end remains within the desired limits, even under heavy load conditions.

3. Loss Reduction: By compensating for the reactive power, shunt capacitors reduce the overall losses in the transmission line. This results in improved efficiency and lower operating costs.

4. Increased Transmission Capacity: Shunt capacitors increase the transmission capacity of the line by reducing the reactive power demand. This allows for the transfer of more active power, thereby maximizing the utilization of the transmission infrastructure.

5. Improved System Stability: Shunt capacitors help in maintaining a stable voltage profile and reducing voltage fluctuations in the system. This improves the overall stability and reliability of the power transmission network.

In summary, shunt capacitors are used for full load compensation in a transmission line to improve the power factor, reduce losses, regulate voltage, increase transmission capacity, and enhance system stability. They are an essential component in power systems to ensure efficient and reliable operation.