Method for improving capacity of multi-feed-in direct current power transmission system against phase commutation failure

Abstract

The invention provides a method for improving the capacity of a multi-feed-in direct current power transmission system against a phase commutation failure. The method comprises the steps of step 1, serially connecting a changeable inductance device with dynamically adjusted reactance on a call wire of any two direct current power transmission systems of the multi-feed-in direct current power transmission system; step 2, monitoring whether each direct current power transmission system has the phase commutation failure or not in real time; step 3, when the condition that any direct current power transmission system has the phase commutation failure is judged, sending a phase commutation failure signal into a reactance regulation controller of the changeable inductance device on each of the call wires of the direct current power transmission system subjected to the phase commutation failure and other direct current power transmission systems, and increasing the reactance values of the changeable inductance devices on the call wires of the direct current power transmission system subjected to the phase commutation failure and other direct current power transmission systems. According to the method for improving the capacity of the multi-feed-in direct current power transmission system against the phase commutation failure, the condition that a once direct current fault causes multiples times of direct current faults in the multi-feed-in direct current power transmission system is avoided.

Description

technical field [0001] The invention relates to the technical field of power transmission and distribution, in particular to a method for improving the ability of a multi-feed direct current transmission system to resist commutation failure. Background technique [0002] With the maturity of DC transmission technology and the rapid development of my country's economy, the level of grid construction continues to improve, and the requirements for long-distance and large-capacity power transmission make multi-infeed DC transmission inevitable. Multi-infeed DC refers to the concentration and placement of multiple DC lines in one area of ​​the receiving end grid. This is the inevitable result of using DC transmission to transmit power to the load center, and it is universal. [0003] However, multiple DC circuits fall into the same AC grid at a short distance so that they have a close electrical connection with each other. This characteristic makes when the AC system fails, the i...

AI Technical Summary

Problems solved by technology

[0003] However, multiple DC circuits fall into the same AC grid at a short distance so that they have a close electrical connection with each other. This characteristic makes when the AC system fails, the instantaneous voltage drop may cause multiple DC transmission lines to alternate successively. phase failure, which affects power transmission and causes unstable operation of the system

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