When you have finished this chapter, you should be able to: List the main types of distance protection characteristics and their advantages and disadvantages. List the measurements used for distance relay comparators. Describe the central electrotechnical distance relays. Explain the operation of the block average comparator. Describe the use of three-zone stepped distance protection. Give the derivation of the residual compensation factor. Describe the operation of different polarization methods and their response to close-up faults. Describe the operation of the standard communication to enhance distance protection schemes. Show how the operation of a directional earth fault protection scheme is used to strengthen a distance protection scheme’s performance. Describe the performance of a distance relay to power swings and the need to inhibit its operation.