Method for determining single-phase short circuit area causing commutation failure

Abstract

The invention provides a method for determining a single-phase short circuit area causing commutation failure, and particularly a method for determining the single-phase short circuit causing the commutation failure based on the positive negative zero sequence impedance matrix. The invention comprises steps of calculating the ratio of the sum of positive negative zero sequence mutual impedance and the positive negative zero sequence self impedance through calculating the positive negative zero sequence self impedance of a transformer station to be studied and the positive negative zero sequence mutual impedance among the inverter stations, determining whether the single-phase short circuit happened in the transformer station can cause the commutation failure of a DC inverter station according to the solved value, obtaining the single-phase short circuit fault area causing multi-loop DC commutation failure through scanning the transformer station to be studied and all inverter stations, and providing reference to studying the impact on the DC system by the AC system short phase short circuit and the power grid operation mode arrangement.

Description

technical field [0001] The invention proposes a method for determining a commutation failure area caused by a single-phase short circuit, in particular a method for determining a commutation failure area caused by a single-phase short circuit based on a positive and negative zero-sequence impedance matrix, which belongs to the technical field of power system analysis. Background technique [0002] With the continuous development of the power system, new features such as AC-DC parallel operation and multi-circuit DC centralized feed-in have appeared in the power grid. The AC-DC system is closely connected and interwoven, and its stability characteristics are complex. Analyzing the interaction between AC system and DC system is a very important issue in power grid planning and operation. [0003] Commutation failure is the most common failure of DC inverters. Most commutation failures in actual operation are caused by voltage disturbances caused by AC grid faults. In a multi...

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Problems solved by technology

However, this calculation method needs to carry out fault simulation on each site that may cause commutation failure, which is heavy workload, long calculation time, and inconvenient to use. Therefore, it is necessary to propose a simple and fast calculation method to determine the Single-phase short-circuit fault area where commutation failure occurs in DC, as a reference for evaluating the influence of AC system on DC system and arrangement of grid operation mode

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