The current carrying capacity of an insulated cable is affected by the losses caused by currents flowing in the metallic sheaths of the cables after the thermal resistance of the cable external environment. Therefore, the load current carrying capacity (ampacity) of the cable can be increased by reducing the current flows in the metal sheath with different connecting methods. Whether the metal sheaths of the cables should be grounded at one end bonded or both ends bonded are still a controversial issue due to different application preferences in power systems. The most important advantage of connecting from two ends provides the protection of the electromagnetic field that it allows an effective shielding. In addition, it provides a return path for low impedance fault current. If the cable shield is bonded from a single point, the electromagnetic field generates a voltage since there is no electrical loop path. The main purpose of special sheath bonding methods is to prevent induced voltage and to reduce sheath losses. In this study, different bonding techniques of the power cables and their effects are discussed. In a power cable supply system, the problem of sheath losses becomes particularly important when higher voltages are induced in the cable sheaths. Studies have shown that in cases where the sheath does not form an electrical loop, such as single point bonding, sheath currents are reduced, but dangerous voltage can occur at the end of the cable
Anahtar Kelimeler: Power cables, ampacity, bonding methods, induced voltage, sheath loses
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