HHT를 이용한 간극이 있는 회전체의 고장진단 = Fault Diagnosis for Rotating Machinery with Clearance using HHT

다국어 초록 (Multilingual Abstract)

Partial rub and looseness are common faults in rotating machinery due to the clearance between the rotor and the stator. These problems are the cause of malfunctions in rotating machinery since those create strange vibrations coming from impact and friction. However, non-linear and non-stationary signals due to the impact and friction are difficult to identify. Therefore, exact time and frequency information are necessary. For those purpose, newly developed time-frequency analysis method, HHT(Hilbert-Huang Transform) is applied to the signals of partial rub and looseness. Comparison of conventional signal processing methods such as FFT, STFT and CWT has been made to verify the effectiveness of fault diagnosis using HHT. The results show that the impact signals are generated regularly when the partial rub is occurred, and then intermittent impact and friction are occurred as the increase of the looseness. Time and frequency information is represented exactly by using HHT.Consequently the features of rotor system with clearances are identified clearly.

목차 (Table of Contents)

• 제1장 서론 = 1
• 1.1 연구배경 = 1
• 1.2 문헌조사 = 2
• 1.3 연구목적 및 방법 = 4
• 제2장 회전기계 실험 = 5
• 2.1 로터회전축 충격실험 = 5
• 2.1.1 로터모드해석 = 5
• 2.1.2 모드해석결과 = 7
• 2.2 부분마멸 실험 = 9
• 2.3 헐거움 실험 = 12
• 제3장 신호처리에 의한 고장진단 = 14
• 3.1 FFT를 이용한 회전체고장진단 = 15
• 3.2 STFT를 이용한 회전체고장진단 = 17
• 3.3 CWT를 이용한 회전체고장진단 = 20
• 제4장 힐버트-후앙 변환 = 23
• 4.1 힐버트변환 = 25
• 4.2 EMD = 29
• 4.3 HHT 개선점 = 37
• 4.4 HHT 특성 = 42
• 4.5 가우시안 필터 = 46
• 제5장 HHT를 이용한 회전체고장진단 = 50
• 5.1 부분마멸이 있는 회전체고장진단 = 50
• 5.2 헐거움이 있는 회전체고장진단 = 54
• 5.2.1 윤활상태 = 54
• 5.2.2 건마찰상태 = 58
• 제6장 결론 = 62
• 참고문헌 = 64