【正文】 實現(xiàn)專家診斷系統(tǒng)的核心是突破知識獲取的瓶頸，用可靠的方式升級數(shù)據(jù)模型，提供專家系統(tǒng)的普及能力。這些 軟件主要是美國 BENTLY 公司開發(fā)的 3300, 3500 and DM2020 系統(tǒng)，美國西屋公司開發(fā)的 PDS系統(tǒng)， ENTECKamp。 模式識別進行集群描述為一系列的過程或事件。 山東交通學院畢業(yè)設計 19 目前，許多方法在診斷推理過程中被采用。傅立葉變換反映信號的整體統(tǒng)計特性，適用于平穩(wěn)信號分析。植物狀態(tài)信息中包含著廣泛的信號，如振動，噪聲，溫度，壓力，應變，電流，電壓等。他們建立了發(fā)電機轉(zhuǎn)子的非線性動力學模型，全面調(diào)查在不同影響下轉(zhuǎn)子的動態(tài)反應，并提出有效的解決方案，以防止轉(zhuǎn)子故障。他建議，典型故障可分為 9 個類型和 37 種 [7]。本文討論了一些里程碑式的觀點。這就是所謂的出 現(xiàn)在近三十年的機械設備故障診斷技術 [1， 2]。2020 年由愛思唯爾公司出版。機械故障占超過 60％的系統(tǒng)故障。 11: 2223. [8] Shiraki T. Mechanical vibration lectures. Zhengzhou: Zhengzhou Mechanical Institute。 Vibration。 Signal processing 山東交通學院畢業(yè)設計 3 1. Introduction With the development of modern science and technology, machinery and equipment functions are being more and more perfect, and the machinery structure bees more largescale, integrated, intelligent and plicated. As a result, the ponent number increases significantly and the precision requirement for the part mating is stricter. The possibility and category of the related ponent failures therefore increase greatly. Malignant accidents caused by ponent faults occur frequently all over the world, and even a small mechanical fault may lead to serious consequences. Hence, efficient incipient fault detection and diagnosis are critical to machinery normal running. Although optimization techniques have been carried out in the machine design procedure and the manufacturing procedure to improve the quality of mechanical products, mechanical failures are still difficult to avoid due to the plexity of modern equipments. The condition monitoring and fault diagnosis based on advanced science and technology acts as an efficient mean to forecast potential faults and reduce the cost of machine malfunctions. This is the socalled mechanical equipment fault diagnosis technology emerged in the nearly three decades [1, 2]. Mechanical equipment fault diagnosis technology uses the measurements of the monitored machinery in operation and stationary to analyze and extract important characteristics to calibrate the states of the key ponents. By bining the history data, it can recognize the current conditions of the key ponents quantitatively, predicts the impending abnormalities and faults, and prognoses their future condition trends. By doing so, the optimized maintenance strategies can be settled, and thus the industrials can benefit from the condition maintenance significantly [3, 4]. The contents of mechanical fault diagnosis contain four aspects, including fault mechanism research, signal processing and feature extraction, fault reasoning research 外文翻譯原文及譯文 4 and equipment development for condition monitoring and fault diagnosis. In the past decades, there has been considerable work done in this general area by many researchers. A concise review of the research in this area has been presented by [5, 6]. Some landmarks are discussed in this paper. The novel signal processing techniques are presented. The advantages and disadvantages of these new signal processing and feature extraction methods are discussed in this work. Then the fault reasoning research and the diagnostic equipments are briefly reviewed. Finally, the future research topics are described in the point of future generation intelligent fault diagnosis and prognosis system. 山東交通學院畢業(yè)設計 5 2. Fault Mechanism Research Fault Mechanism research is a very difficult and important basic project of fault diagnosis, same as the pathology research of medical. American scholar John Sohre, published a paper on Causes and treatment of highspeed turbo machinery operating problems (failure), in the United States Institute of Mechanical Engineering at the Petroleum Mechanical Engineering in 1968, and gave a clear and concise description of the typical symptoms and possible causes of mechanical failure. He suggested that typical failures could be classified into 9 types and 37 kinds [7]. Following, Shiraki [8] conduced considerable work on the fault mechanism research in Japan during 60s70s last century, and concluded abundant onsite troubleshooting experience to support the fault mechanism theory. BENTLY NEVADA Corporation has also carried out a series experiments to study the fault mechanism of the rotorbearing system [9]. A large amount of related work has been done in China as well. Gao et al. [10] researched the vibration fault mechanism of the highspeed turbo machinery, investigated the relationship between the vibratio