TT, TN distribution system

Abstract

The invention provides a TT, TN distribution system (800, 810, 820). The distribution system (800, 810, 820) is provided with at least one protective device (100-1, 100-21, 100-22...) and at least oneelectronic controller, and is characterized in that a power supply of the electronic controller is obtained from the distribution system (800, 810, 820), at least one current collector (300) is arranged on N lines corresponding to the protective device (100-1, 100-21, 100-22...), and the rated current value of the current collector (300) is not greater than 20% of the rated current of the N line.The protective device disclosed by the invention realizes the functions of detecting and protecting N line breakage under the condition of three-phase current unbalance which causes damage to a loadand will affect the normal operation of the load, thereby enabling the protection function setting of the protective device to be more scientific, reasonable and perfect, and enabling the operation ofthe power grid to be safer. Meanwhile, the TT, TN distribution system achieves the goal of enabling the traditional electric power protection device to have the above functions at a low cost, therebyhaving an extremely high cost-performance ratio.

Description

technical field [0001] The invention is applied to the field of three-phase four-wire power distribution, and particularly relates to a TT and TN power distribution system. Background technique [0002] In the three-phase four-wire power supply system, the N wire keeps the three-phase voltage balanced and stable, and the neutral point will not shift due to the imbalance of the three-phase load, resulting in abnormal power supply. If the N wire is disconnected, the three-phase The unbalanced load makes the three-phase voltage unbalanced, and the voltage at both ends of the load of each phase may rise or fall abnormally. The phase with too high voltage may burn out the electrical equipment and cause property losses to users; the phase with too low voltage may The electrical equipment that will be used cannot work normally, seriously affecting the reliability of power supply. Therefore, it is necessary to detect and protect the disconnection of the N line. Integrating the N l...

AI Technical Summary

Problems solved by technology

[0002] In the three-phase four-wire power supply system, the N wire keeps the three-phase voltage balanced and stable, and the neutral point will not shift due to the imbalance of the three-phase load, resulting in abnormal power supply. If the N wire is disconnected, the three-phase The unbalanced load makes the three-phase voltage unbalanced, and the voltage at both ends of the load of each phase may rise or fall abnormally. The phase with too high voltage may burn out the electrical equipment and cause property losses to users; the phase with too low voltage may Can use electrical equipment and fail to work normally, seriously affecting the reliability of power supply

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