The breakdown classification of sensor reachs diagnostic method

The size that presses sensor breakdown rate by classification of sensor breakdown rate can be divided for hard breakdown and soft breakdown. The trouble that attaint of structure of hard breakdown generally refer to causes, general amplitude is bigger, change is abrupt the mutation of character of generally refer to of; soft breakdown, amplitude is lesser, change is slow. Hard breakdown also weighs complete breakdown, the measured value when complete breakdown does not follow real change and change, maintain some reading from beginning to end. Normally this one constant the value is 0 the biggest perhaps reading commonly. Breakdown measured value is a level roughly linear. Soft breakdown includes the demote below data deviation, drift, accuracy class. Soft breakdown is relatively lesser, be hard to discover, accordingly, will tell from some kind of meaning, soft breakdown harm is greater than hard breakdown harm, its endanger what caused people gradually to take seriously. 2.

The expression that the expressional classification that exists by breakdown exists by breakdown can be divided for intermittence breakdown and permanent breakdown. After invalidation of permanent breakdown of; of intermittence breakdown stand or fall, cannot return to normal again. 3.

The process of breakdown happening, development can divide the process classification basis according to breakdown happening, development to change for choppy breakdown gentle breakdown. Rate of change of signal of barrier of misfortune of delay of big; of rate of change of choppy fault signal is minor. 4.

The reason classification that presses breakdown can be divided by breakdown reason for deviation breakdown, pound breakdown, open circuit breakdown, drift breakdown, short circuit breakdown, periodic interference, nonlinear dead band breakdown. The breakdown reason of deviation breakdown is: Slant the breakdown reason of the; concussion breakdown such as buy electric current or bias voltage is: The random interference in power source and ground wire, surge, electric spark discharges, the breakdown reason of the breakdown of; open a way such as the burr in D/A transformer: Line breaks, the breakdown account that chip pin did not link breakdown of classy; drift: Lukewarm the breakdown reason that waits for breakdown of; short circuit: The bridge road that pollution causes corrodes, circuit weak point receives the breakdown consideration that waits for; periodic interference: The; such as interference of power source 50Hz is nonlinear the breakdown reason of dead band breakdown: Amplifier saturation, contain nonlinear link. Additional, from build model, emulated angle to set out, can divide increase sexual trouble to be mixed by sexual breakdown. To slanting buy breakdown, on one is added on former signal constant or; of random small signal is disturbed to concussion, can go up in former signal overlay; of signal of a pulse to short circuit breakdown, signal is close to breakdown of open a way of Yu Ling; , signal is close to sensor to output breakdown of maximum; drift, signal with breakdown of periodic interference of; of former signal of some rate deflection, the signal of frequency of some of the overlay on former signal. The diagnostic method of sensor breakdown sets out from different point of view, the classification of breakdown diagnostic method is not identical. Diagnose breakdown simply methodological cent to be now: Be based on the method of analytic maths model and the method that do not rely on mathematical model. 1.

The methodological basis incomplete that is based on analytic maths model differs the form of generation to differ, the method that is based on analytic maths model can divide further for: Parameter estimation technique, condition estimation technique and law of equal in value space. The breakdown that is based on a model diagnoses a method, it is the diagnostic method that a kind of the earliest development rises, also be the diagnostic method with a kind of research, the widest application at the same time. The advantage is model mechanism is clear about, the structure is simple, yi Shi shows, easy analysis, can diagnose in real time. In breakdown diagnostic domain has important place, the main research direction of sensor breakdown diagnostic method still can is in the development henceforth. Defect is computation the amount is large, complex; puts the system in the error that build a model, the dependability of adaptability poor; of the model is poor, appear easily to sign up for by accident, the phenomenal; such as fail to report sth is exterior disturbing rash club sex, systematic noise and interference are not sensitive. Current, the research achievement of this kind of diagnostic method basically still is centered at linear system, nonlinear to thorough research current trouble of the system diagnoses a technology to have important sense, in the meantime, problem of rash club sex also has very high research value. A few breakdown in expressing L to introduce model law diagnose methodological advantage and defect. The comparison of the advantage of diagnostic method of a few breakdown in expressing 1 model law and defect 2.

The breakdown that does not rely on mathematical model diagnoses a method current, control system becomes more and more complex, as a result of actual in the model of accurate and analytic maths that builds control system very hard, when existence builds modular error, the breakdown that is based on a model diagnoses a method to will appear to sign up for by accident, the phenomenon such as fail to report sth, because this does not rely on the breakdown of the model,diagnosed a method to be taken seriously by the height of people. The advantage of the method that does not count mathematical model is the accurate model that does not need a boy or girl friend, and adaptability is strong. Its defect is a structure complex, be hard to come true. This kind of breakdown that does not rely on systematic model diagnoses a method to be able to divide the breakdown that is the method that is based on data drive to diagnose the method, breakdown that is based on knowledge to diagnose method and the method that are based on disperse incident to wait. The method that is based on data drive is based on the method of data drive to have two kinds big: Signal processing technique and statistical method. The commonly used a few breakdown that are based on signal processing diagnose a method to have: Absolute value examines with the trend, the breakdown that uses Kullback information standard detects, be based on the breakdown that gets used to slip Lattice filter oneself to detect method, the breakdown that is based on signal mode estimation detects method of the method is relevant analysis law, small analysis and information confluence method. The breakdown that is based on intellectual method to be based on knowledge diagnoses a method assist can divide the breakdown to be based on a symptom to diagnose method and the breakdown that are based on qualitative model to diagnose a method two kinds. Be based on the method of disperse incident to be based on the breakdown of disperse incident to diagnose a method is diagnostic method of a kind of when in recent years development rises new-style breakdown. Its are basic the thought is: The condition of disperse incident model mirrors whack already, mirror systematic state of fault again. Watch 2 gave out of the progress that the advantage of diagnostic method of a few breakdown and defect study as theory and technical level rise ceaselessly, the seminar that sensor breakdown diagnoses more tend practical change, a few in actual in the problem that encounter can get settlement stage by stage. CNC Milling CNC Machining