what role does transmission line termination take in long distance power lines?
Power transmission lines are not terminated with a resistance in the way that data transmission lines are. As a result, there is reflection on power transmission lines. The voltage near the end of a power transmission line is often higher than at its source. This is known as the Ferranti effect. Power utilities compensate for the Ferranti effect by having step-down distribution or service transformers with a variety of taps on them. Distribution or service transformers provide the final &quot;mains&quot; voltage for end-users. Which tap is selected on the service transformer depends upon the voltage on the transmission line where the transformer is located. Thus, although the transmission line voltage varies from point to point, the &quot;mains&quot; voltage supplied to end users can generally be kept within 10% of nominal (in the US).