Measuring point selection method in analog circuit fault diagnosis

Abstract

The invention discloses a measuring point selection method in analog circuit fault diagnosis. The method includes the steps that firstly, in a preset tolerance range, fault analog simulation is conducted on a circuit, so that measured data of measuring points of faults are obtained; then, the measuring points are selected through a measuring point selection algorithm based on heuristic mode graph searching, root nodes are initialized firstly and serve as target nodes, all the measuring points in a measuring point set are adopted as successor nodes to expand the target node, simulation data of one measuring point corresponding to each successor node are screened according to data identification, fuzzy groups are divided according to screened address data, the probability of occurrence of the fuzzy groups is obtained, information entropy of each successor node is calculated, the node with the smallest information entropy is selected as the optimal node and deleted from the measuring point set, and the optimal node serves as a target node and is expanded continuously until the information entropy is zero or the measuring point set is empty. According to the method, the measuring points can be preferably selected, so that an optimal measuring point selection scheme is obtained, and fault diagnosis is achieved through fewer measuring points.

Description

technical field [0001] The invention belongs to the technical field of fault diagnosis of analog circuits, and more specifically relates to a method for selecting measuring points in fault diagnosis of analog circuits. Background technique [0002] The fault dictionary technology belongs to the pre-test simulation method, and is currently a relatively effective fault diagnosis method for analog circuits. The problem of measuring point selection of fault dictionary has been widely concerned, and practice has proved that the integer coding method is an effective tool for measuring point selection. Integer coding technology comes from the concept of fuzzy group. Hochwald et al. first proposed the concept of fuzzy group in their literature. For any given node, there may be many fault signals (such as voltage value, etc.) generated on this node are very small. so that these failures are indistinguishable on this node. These failures are said to belong to the same fuzzy group. ...

AI Technical Summary

Problems solved by technology

[0015] This encoding technique is simple to implement, but has two defects: one is to set the variation range of all fault voltages on all measuring points as a fixed range (such as the commonly used 0.7V) standard

[0016] The second flaw is the independent assumption of measuring points, that is, it is assumed that fault voltages are independent of each other at different measuring points

Images