Converter valve state evaluation method based on hierarchical graded fuzzy theory

Abstract

As the core equipment of the DC power transmission project, the operation status of the converter valve is the key to the safety and stability of the DC system. Existing assessment methods cannot accurately assess the health status of the converter valve in project operation. According to the independence of the function and structure of each component of the converter valve, this paper proposes a converter valve state evaluation method based on hierarchical grading fuzzy theory. The data used are various information characterizing the state of the converter valve, such as voltage, current, sound, image, and other data. According to hierarchical grading, the evaluation index system is constructed. Based on the fuzzy theory, the affiliation function is proposed, and the affiliation probability of four hierarchical states is output for the state evaluation results of the converter valve and its group components. Experiments show that the method improves the accuracy and practicability of converter valve evaluation in engineering sites.