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電源系統未知インダクタンスにロバストなPWM コンバータのアクティブダンピング制御
Full text link九州工業大学博士学位論文（要旨）学位記番号：生工博甲第261号 学位授与年月日平成28年3月25
Robust Active Damping Control for a PWM Converter Connected to Unknown Inductance of Power Grid
No full text九州工業大学博士学位論文 学位記番号:生工博甲第261号 学位授与年月日:平成28年3月25日1章 緒論||2章 PWM コンバータシステムのモデル化と問題点||3章 提案手法による振動抑制制御||4章 シミュレーション||5章 実機検証||6章 結
Development of Stereo Vision System Using Hierarchical Gradient Feature on FPGA for Mobile Robots
No full text九州工業大学博士学位論文 学位記番号:工博甲第419号 学位授与年月日:平成28年3月25日第1章 序論||第2章 画像局所特徴量による検出器および記述子||第3章 階層構造化された勾配特徴量によるステレオビジョンの構築||第4章 ステレオビジョンの検証実験||第5章 結
FFTと連続ウェーブレット変換法を用いた同期位相計測に基づく電力システムのモード検出とダンピング推定
Full text link九州工業大学博士学位論文 学位記番号:工博甲第413号 学位授与年月日:平成28年3月25日1. INTRODUCTION||2. SYNCHROPHASOR MEASUREMENT AND THE METHOD OF ANALYSIS||3. FAST FOURIER TRANSFORM AND CONTINUOUS WAVELET TRANSFORM APPROACH||4. APPLICATION OF THE APPROACH FOR MODE AND DAMPING CALCULATION||5. WIDE AREA SIGNAL DAMPING CONTROLLER||6. CONCLUSION AND FUTURE WORKThe thesis carries out the estimation of damping as well as the frequency
mode of inter area oscillations in the range of 0.1 to 1.0 Hz. This belongs under
the topic of angle stability management of power systems. Previously some other
studies had been conducted in this area at which most of them employed the
methods such as the least squares, Yule-Walker, autoregressive (AR),
autoregressive moving average (ARMA), the Kalman filter and the subspace
method. Another research also had been conducted which based on Fast Fourier
Transform (FFT) analysis individually, the damping ratio and frequency
oscillation were estimated from eigenvalue of the matrix associated to a Single
Machine Infinite Bus (SMIB) model. An output-only-based simplified oscillation
model was developed to estimate the characteristic of inter-area power oscillation
based on extracted oscillation data. However, this previous method did not
explain how to calculate damping ratio without considering any simplified model.
Furthermore, the behavior of the signal during certain time of analysis could not
be described.
This thesis promotes a novel approach in analyzing PMU data based on
Fast Fourier Transform (FFT) and Continuous Wavelet Transform (CWT)
algorithm. Then proceed by demodulating the slicing signal at a particular peak
and ridge of the signal using a decrement technique. The approach applied in this
thesis can be classified into the non-parametric approach, where it works directly
on the data. The damping calculation method in this thesis emphasized on the
accurate and robust damping estimations which was proved by attempting the
simulation towards various level of signal to noise ratio (SNR).
To verify the outcome of this method a synthesized signal contains of
three ringdown modes representing a real signal from PMU was analyzed. The
results were compared to the given parameters and it was clearly shown that this
method gave the result within an acceptable range of error. Additionally, the
acceptability of this method was also verified by comparing to the result of
eigenvalue-based calculation on a standard power system model. The simulation
indicated the results of the two approaches fitted each other means this FFT-CWT
is workable to assess the damping ratio of a small signal oscillation in power
system. The advantage of this method is no prior data of the system required;
hence this approach is very applicable in the power system where gathering data
from the network is not attainable.
This thesis also elaborated the application of wide area signal recorded by
PMU, refined by the FFT-CWT method, for controlling the oscillation damping of
power system. The simulation showed the application of wide area signal as an
input to the damping controller has a great prospective to countermeasure the inter
area oscillation in the system
Evaluation of Tsunami Force Acting on the Structure
No full text九州工業大学博士学位論文 学位記番号:工博甲第411号 学位授与年月日:平成28年3月25日第１章 序論||第２章 橋梁に作用する津波の作用力評価に関する既往の研究と課題||第３章 東日本大震災の概要とマクロ的被害の分析||第４章 地域毎の詳細な被害の分析||第５章 数値解析で評価される橋梁に作用する津波特性の適用範囲の検討||第６章 結
IGBT Avalanche Current Filamentaion Ratio: Precise Simulations on Mesh and Structure Effect
Full text linkISPSD 2016 28th International Symposium on Power Semiconductor Devices and ICs., Jun 12-16, 2016, Žofín Palace, Prague, Czech RepublicCurrent filamentaion effect with dynamic avalanche during turn-off transient in IGBT has been discussed for years. In the prior papers, the possibility of device failure has been reported based on TCAD simulation and simulation results have shown that variety of filamentation phenomena exist for conditions assumed in each simulation. It is discussed in this paper, for the first time, that the relationship of filamentation current concentration strength to device design parameters and categorizes filamentation phenomena, introducing current filamentation ratio (CFR). In the paper, guidelines for appropriate mesh pattern selection are also described to ensure the validity of simulation results
Study of Industrial Parts Defect Detection Method based on Image Processing
No full text九州工業大学博士学位論文 学位記番号:情工博甲第316号 学位授与年月日:平成28年9月23日第1章 諸言||第2章 目視検査をモデルとした提案手法の着眼点||第3章 コーナー特徴の分散に基づく欠陥検出手法||第4章 照明環境を変更した複数枚画像に基づく欠陥検出手法||第5章 結
バイオレメディエーションとバイオエネルギー生産のための細菌間相互作用を理解するための微生物群集動態解析
Full text link九州工業大学博士学位論文（要旨）学位記番号：生工博甲第275号 学位授与年月日：平成28年12月27
New Toxicity Testing Method of Chemicals Using Cultured Mammalian Cells
No full text九州工業大学博士学位論文 学位記番号:生工博甲第277号 学位授与年月日:平成28年12月27日第１章 緒言||第２章 CHL細胞の染色体異常試験を通じた細胞核のスエリング||第３章 L5178Y細胞を用いた細胞核のスエリング||第４章 考察||第５章 総