An active closed-loop distribution network protection system and method

Abstract

The invention discloses an active closed loop power distribution network protection system and a method. The active closed loop power distribution network protection system comprises that: an outlet circuit of a transformer station is successively connected to multiple nodes to form a closed loop network; a wire outlet protection device is positioned at the outlet of the transformer station, which adopts the overcurrent principle and is used as a backup of the whole looped network; each of the nodes is provided with a protection terminal unit; the connection part of each node is provided with a current mutual inductor; the protection terminal unit can realize various protection functions; the protection terminal unit collects input signals collected by current mutual inductors of the nodes and performs bus protection according to the input signals; the overcurrent principle is adopted to perform load protection on the connection wire of the node which is connected to loads; and the longitudinally-connected protection is performed according to the input signal collected by the current mutual inductor on the corresponding connection wire and current phase angle changing direction signal of another node which is connected through the connection wire. The invention can accurately the distribution network faults of different positions, can effectively solve the condition that the fault current amplitude is too small and can accurately determine the fault.

Description

technical field [0001] The invention relates to an active closed-loop distribution network protection system and method. Background technique [0002] The existing urban distribution network in my country mostly adopts the structure of multi-segment and multi-connection, and the operation mode usually adopts closed-loop design and open-loop operation. Generally, a relatively simple protection device is configured, and the distribution automation system realizes the isolation of the faulty section and the recovery of power supply for the non-faulty section. The characteristic of this structure is that the protection configuration is simple, and generally the protection is only set at the line exit, so the entire line must be cut off in case of a fault. Since short-term power outages are required for fault isolation and switching operations when power is restored after a fault, the continued improvement of power supply reliability is limited. In addition, the open-loop opera...

AI Technical Summary

Problems solved by technology

Most of the existing protection schemes only provide a protection principle that can identify the fault section to protect the transmission lines of the distribution network, but rarely consider the impact of the protection action, and seldom consider the entire active area as a whole. Construction of Distribution Network Protection System

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