Multi-infeed power transmission system fault partition current limiter installation method based on graph theory

Abstract

The invention discloses a multi-infeed power transmission system fault partition current limiter installation method based on a graph theory. The method comprises the steps that an alternating-current network with a direct-current drop point is extracted to be a graph, all generatrices form a vertex set of the graph, and all alternating-current lines form a frontier set of the graph. Two weights w1 and w2 are given to each edge of the graph and correspond to a relative value of a tide mode and a serial number of the edge; sorting is performed according to the size of all the weights w1, and fault current limiters are installed on the edges with the w1 larger than 1 for grouping. A direct-current system inversion side extinction angle is used as the judgment standard, and step-by-step optimization is performed through a continuous simulation method to obtain the minimum current limiter combination meeting the requirement. According to the method, power grid partitioning and fault isolation can be effectively achieved after a fault occurs, it is ensured that no simultaneous commutation failure occurs on a multi-infeed power transmission system, and the effectiveness of the method is verified.

Description

technical field [0001] The invention relates to a graph theory-based method for installing a current limiter for fault zones in a multi-infeed power transmission system. Background technique [0002] With the rapid development of my country's DC transmission technology and the implementation of energy strategies such as "south-to-north power transmission" and "west-to-east power transmission", East China Power Grid and Southern Power Grid have formed a multi-infeed AC-DC system. According to the national grid planning, more DC systems will fall into the AC grid in the future. Compared with pure AC system and single-infeed DC system, the interaction characteristics between multi-infeed DC transmission systems have a great influence on the safe and stable operation of the entire system. [0003] Commutation failure is one of the most common faults in DC systems. In the multi-infeed DC transmission system, the inverter stations are coupled to each other through the AC system ...

AI Technical Summary

Problems solved by technology

This method can theoretically achieve partitioning of the AC grid, but it is quite difficult to implement

First of all, system emergencies can be of various types, which cannot be generalized into one, and for large-scale AC systems, the amount of calculation or the number of simulations will be very large

Secondly, there is great uncertainty in the installation position of the fault current limiter

At the same time, the above method only proposes a general partition method without verification

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