압전소자를 이용한 정밀위치 추정기와 전력변환 장치에 관한 연구 = A study on a precision position estimator and an energy harvesting device using a piezoelectric material

다국어 초록 (Multilingual Abstract)

A piezoelectric materials have both the reverse and the direct piezoelectric effect.
This study deals with all of them as follows :
First, this paper deals with the analytical modeling, and the experimental verification of the strain self-sensing. Three strain self-sensing methods are investigated, which are a conventional method of a capacitance bridge, an adaptive filter, and the phase delay compensation in order to minimize the effect of the phase delay from a piezoelectric material. The piezoelectric beam consists of two laminated lead zirconium titanates(PZT) on a metal shim and generates bi-directional movement. A mathematical model of the beam dynamics is derived by the Hamilton’s principle and the accuracy of the modeling is verified through the comparison with experiment results. The efficacy of these methods is investigated through the comparison of experimental results with the prediction from the derived analytical model.
Second, this paper deals with a problem of vibration suppression of a piezoelectric beam using a self-sensing algorithm. Two methods, which are PPF(positive position feedback) and SRF(strain rate feedback), are considered to suppress a residual vibration of a piezoelectric beam developed during the step positioning of a beam end point. A self-sensing algorithm treated here is basically a strain estimator of a beam movement and is to be used for the closed loop control. The efficacy of the proposed idea is evaluated through experiments.
Third, an analytic and experimental study on the usefulness of the adaptive piezoelectric energy harvesting device as a wireless electrical power supply when it is driven by mechanical vibrations of low frequency are covered. For this purpose, an adaptive control technique and a step-down converter are used. A THUNDER series a piezoelectric material (TH7-R), which has been developed by a NASA engineer is selected for this study. In order to provide a mechanical energy to the piezoelectric material, a mechanical motion vibrator is designed. The adaptive controller is implemented using a dSPACE DS1104 controller board. The DC-DC converter with an adaptive control technique extracts 5-times more power from the TH7-R than that using a direct charging without the converter. The other energy harvesting method which is the SSHI(synchronized switching harvesting with inductor) is also investigated for its usefulness as a small power source.

목차 (Table of Contents)

• I. 서론 = 1
• 1. 정밀위치 추정기에 관한 선행연구 = 5
• 2. 전력변환 장치에 관한 선행연구 = 9
• Ⅱ. 압전소자를 이용한 정밀위치 추정기 = 11
• 1. 개요 = 11
• 2. 압전소자의 해석적 운동 모델 = 15
• 3. 압전소자의 자기계측 = 20
• 1) 압전소자의 특성 = 20
• 2) 최초의(original) 스트레인 추정 자기계측 = 21
• 3) 적응 필터(adaptive filter)를 사용한 스트레인 추정 자기계측 = 23
• 4) 스트레인 자기계측에 대한 결과 = 26
• 5) 위상지연을 보상한 스트레인 자기계측 = 32
• 4. 잔류진동억제 알고리즘 = 36
• 1) PPF = 36
• 2) SRF = 40
• 3) PPF와 SRF를 이용한 잔류진동 억제 성능 실험 = 44
• 4) 자기계측 회로를 이용한 잔류진동 억제 성능 비교 실험 = 48
• Ⅲ. 압전소자를 이용한 전력변환 장치 = 54
• 1. 개요 = 54
• 2. 적응 제어기를 이용한 에너지 회수에 대한 연구 = 57
• 1) 연구 목표 및 방법 = 57
• 2) 연구 결과 및 고찰 = 66
• 3) 결론 = 72
• 3. 동기화 스위칭 에너지회수법(SSHI)을 이용한 에너지 회수에 대한 연구 = 73
• 1) 변환 회로 = 73
• 2) 실험 장치 = 75
• 3) 결과 및 토의 = 76
• 4) 결론 = 77
• 4. 결론 = 82
• Ⅳ. 결론 및 향후 연구 분야 = 83
• 참고문헌 = 86
• 부록 = 90
• Abstract = 100