Composite fault diagnosis method for hydraulic AGC system

Abstract

The invention discloses a composite fault diagnosis method for a hydraulic AGC system. The method specifically comprises the following steps: S1, mill component dynamic modeling: acquiring the equivalent of each link of a hydraulic AGC system to get a mathematical model thereof; S2, system modeling: simulating a fault, selecting a measuring point, building a multi-signal model of the system, and getting a fault dependence matrix under the multi-signal model; and if the fault is a single fault, getting a fault dependence matrix directly, performing fault diagnosis, and getting a result directly; S3, if the fault is a composite fault, using a blind source separation algorithm to blindly separate measuring point information, getting a fault dependence matrix, and diagnosing the composite fault; and S4, fault diagnosis: after the system fails, getting the information of the measuring point, and locating the fault source by comparing the measuring point information with the fault dependence matrix. Through the diagnosis method of the invention, the purpose of composite fault isolation and location is achieved, and the fault separation rate is improved.

Description

technical field [0001] The invention belongs to the technical field of system fault diagnosis, and specifically refers to a compound fault diagnosis method of a hydraulic AGC system. Background technique [0002] Hydraulic AGC is a system that uses the hydraulic system of the rolling mill to control the position of the roll by adjusting the oil volume and pressure of the hydraulic cylinder through the hydraulic servo valve, thereby automatically controlling the thickness of the strip. It is worth noting that the AGC system has many frequent faults such as abnormal servo valve gain, oil pipe leakage, and displacement sensor failure. The failure of the AGC system may destroy the normal rolling state of the entire rolling mill, and even lead to equipment safety hazards such as rolling mill vibration and serious quality accidents such as strip slipping, deviation, broken strip, and stacked steel. Because the AGC system has a multiple closed-loop control structure, even a small ...

AI Technical Summary

Problems solved by technology

Failure of the AGC system may destroy the normal rolling state of the entire rolling mill, and even lead to equipment safety hazards such as rolling mill vibration and serious quality accidents such as strip slipping, deviation, broken strip, and piled steel

Because the AGC system has a multiple closed-loop control structure, even a small state abnormality will propagate and diffuse through the closed loop to cause serious equipment failures, and even complex failures that are difficult to handle; once a failure occurs, it is difficult to isolate the failure and positioning

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