Method for monitoring health of rotary machine suitable for working condition changing condition

Abstract

The invention relates to a method for monitoring health of a rotary machine suitable for a working condition changing condition. The method comprises the steps that (1) a monitor model is constructed, wherein a relevance vector machine is used for fitting the function relation of health characteristic parameters and a working condition, the function relation is used as the parameters of a self-adaption threshold model, and the self-adaption threshold model is constructed; (2) a health state is monitored, wherein through test signals of the rotary machine to be detected, the constructed self-adaption threshold model is used for detecting whether test data exceed a threshold value or not, the machine is judged to be healthy if the test data do not exceed the threshold value, and otherwise, the machine is judged to break down. According to the method, the relevance vector machine is used for fitting the mean value of health characteristics and the function relation of standard deviation changing along with working condition parameters, and the method has the advantages that the relevance vector machine has strong learning capacity, the problems of the local minimum, the over-fitting and the under-fitting of a neural network can be solved, the relevance vector machine has better sparsity than a support vector machine, and obtained results are simpler and more practical. The method has the advantages of being high in monitor precision and capable of being used under rotating speed changing and load changing conditions.

Description

technical field [0001] The present invention mainly relates to the field of health monitoring and fault diagnosis, in particular to a kind of health monitoring using correlation vector machine and self-adaptive threshold model, which is mainly applicable to the diagnosis of various rotating machinery faults under the condition of changing working conditions. health monitoring. Background technique [0002] Changing complex working conditions and uncertain external environmental disturbances are an important factor affecting mechanical health monitoring and fault diagnosis. In fact, the operating conditions of many rotating machines are not the usual settings of constant speed and constant load. For example, when an aircraft is idling, climbing, leveling, and landing, the rotational speed and output power of the engine vary greatly. In the process of health monitoring of mechanical equipment, some processing methods that are very effective at constant speed and constant loa...

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Problems solved by technology

) The above methods provide a way for the vibration signal analysis under variable speed conditions, but these methods do not consider that the normal contact impact energy and the impact vibration energy caused by faults will change when the speed, output power, and especially the load change

Considering that the system response changes caused by faults, especially early faults, are often very weak, it becomes very difficult to identify whether the vibration response changes of machinery are caused by changes in working conditions or fault states.

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