Power/voltage stability margin assessment method of alternating current/direct current mixed-linkage electrical power system with multi-infeed direct current

Abstract

The invention relates to a power / voltage stability margin assessment method of an electrical power system, and provides a power / voltage stability margin assessment method of an alternating current / direct current mixed-linkage electrical power system with multi-infeed direct current. The method involves an equivalent mode for equalizing a complex power grid as a simple power grid, a calculation method for power / voltage stability margin index (PVSI) of the electrical power system and determination of a power / voltage stability boundary of the electrical power system. The method has the advantagesthat 1, the complex power grid with various elements is equalized as the simple power grid to provide convenience for all sorts of electrical power system analysis and control techniques; 2, the power / voltage stability margin index is adopted for conducting on-line measurement on the power / voltage stability margin of the electrical power system under a dynamic situation, and identifying the weaknodes of a network; 3, the value of the power / voltage stability margin index is compared with the power / voltage stability boundary to judge whether or not the electrical power system is stable, and guidance can be provided for on-line control.

Description

technical field [0001] The invention relates to a method for evaluating the power / voltage stability margin of a power system, in particular to a method for evaluating the power / voltage stability margin of an AC / DC hybrid power system with multi-infeed direct current. Background technique [0002] At present, the power / voltage stability evaluation methods of AC / DC hybrid power systems can be divided into two types: methods based on short-circuit ratio and methods based on sensitivity. [0003] The method based on the short-circuit ratio calculates the short-circuit ratio and effective short-circuit ratio at the AC-DC common coupling point, and measures the degree of interaction between different DCs according to the structure and operation status of the system, and obtains the multi-infeed short-circuit ratio and multi-infeed effective short-circuit ratio. Short-circuit ratio, multi-infeed critical effective short-circuit ratio and other indicators; the method based on sensit...

AI Technical Summary

Problems solved by technology

Both the short-circuit ratio method and the sensitivity method have various deficiencies. For example, the sensitivity method can only be used in a steady state and cannot evaluate the system in real time online, while the short-circuit ratio method is mainly used for qualitative judgment and cannot accurately determine the stable boundary of the system. , and is not easily applied to the transient case

In the actual large-scale power system, these two methods are also difficult to fully consider various complex components in the system

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