http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
SVPWM Strategies for Three-level T-type Neutral-point-clamped Indirect Matrix Converter
Nguyen Dinh Tuyen,Le Minh Phuong,이홍희 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.4
In this paper, the three-level T-type neutral-point-clamped indirect matrix converter topology and the relative space vectormodulation methods are introduced to improve the voltage transfer ratio and output voltage performance. The presentedconverter topology is based on combinations of cascaded-rectifier and three-level T-type neutral-point-clamp inverter. It canovercome the limitation of voltage transfer ratio of the conventional matrix converter and the high voltage rating of powerswitches of conventional matrix converter. Two SVPWM strategies for proposed converter are described in this paper to achievethe advantages features such as: sinusoidal input/output currents and three-level output voltage waveforms. Results from Psim9.0 software simulation are provided to confirm the theoretical analysis. Hence, a laboratory prototype was implemented, and theexperimental results are shown to validate the simulation results and to verify the effectiveness of the proposed topology andmodulation strategies.
A Carrier-Based Pulse Width Modulation Method for Indirect Matrix Converters
Dinh-Tuyen Nguyen,Hong-Hee Lee,Tae-Won Chun 전력전자학회 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.3
This paper proposes a carrier-based pulse width modulation (PWM) method to control an indirect matrix converter (IMC) by analyzing the relationship between the space vector PWM (SVPWM) and the carrier-based PWM. The complexity of the SVPWM method for an IMC can be reduced by using an equivalent carrier-based PWM method. The advantage of the proposed algorithm is its ability use only one symmetrical triangular carrier signal to generate the gate signals for all of the power switches in both the rectifier and inverter stages as compared to the conventional method where the carrier signal used in the rectifier stage is different from that of the inverter stage. In addition, by using a suitable offset voltage component in the modulation signals, the output voltage magnitude reaches 0.866 of the input voltage magnitude. Simulation and experimental results are provided in order to validate the proposed method.
A Carrier-Based Pulse Width Modulation Method for Indirect Matrix Converters
Nguyen, Dinh-Tuyen,Lee, Hong-Hee,Chun, Tae-Won The Korean Institute of Power Electronics 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.3
This paper proposes a carrier-based pulse width modulation (PWM) method to control an indirect matrix converter (IMC) by analyzing the relationship between the space vector PWM (SVPWM) and the carrier-based PWM. The complexity of the SVPWM method for an IMC can be reduced by using an equivalent carrier-based PWM method. The advantage of the proposed algorithm is its ability use only one symmetrical triangular carrier signal to generate the gate signals for all of the power switches in both the rectifier and inverter stages as compared to the conventional method where the carrier signal used in the rectifier stage is different from that of the inverter stage. In addition, by using a suitable offset voltage component in the modulation signals, the output voltage magnitude reaches 0.866 of the input voltage magnitude. Simulation and experimental results are provided in order to validate the proposed method.
SVPWM Strategies for Three-level T-type Neutral-point-clamped Indirect Matrix Converter
Tuyen, Nguyen Dinh,Phuong, Le Minh,Lee, Hong-Hee The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.4
In this paper, the three-level T-type neutral-point-clamped indirect matrix converter topology and the relative space vector modulation methods are introduced to improve the voltage transfer ratio and output voltage performance. The presented converter topology is based on combinations of cascaded-rectifier and three-level T-type neutral-point-clamp inverter. It can overcome the limitation of voltage transfer ratio of the conventional matrix converter and the high voltage rating of power switches of conventional matrix converter. Two SVPWM strategies for proposed converter are described in this paper to achieve the advantages features such as: sinusoidal input/output currents and three-level output voltage waveforms. Results from Psim 9.0 software simulation are provided to confirm the theoretical analysis. Hence, a laboratory prototype was implemented, and the experimental results are shown to validate the simulation results and to verify the effectiveness of the proposed topology and modulation strategies.
Novel Single-state PWM technique in Multilevel Inverter for unbalanced dc sources
Nguyen Van Nho,Hong Hee Lee,Nguyen Dinh Tuyen 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-
Single-state PWM technique (SS PWM0 presents an optimised switching losses PWM scheme to be applied for multilevel inverter for possible reducing number of switchings in a sampling period. Nonlinear control characteristics and harmonic distortion factor can be significantly improved if the number of levels is high. To implement a single- state PWM control with minimised voltage error on condition of unbalance dc sources, a compensating technique is required. The paper will propose a possible solution for implementing the SS PWM with minimised voltage error, using carrier based approach. This again demonstrates the utilisation of carrier based and space vector PWM relationship in solving various optimised PWM problems in multilevel inverters.
Tran, Van Cuong,Nguyen, Ngoc Thanh,Fujita, Hamido,Hoang, Dinh Tuyen,Hwang, Dosam Elsevier 2017 Knowledge-based systems Vol.132 No.-
<P><B>Abstract</B></P> <P>In recent years, many applications in natural language processing (NLP) have been developed using the machine learning approach. Annotating data is an important task in applying machine learning to NLP applications. A common approach to improve the system performance is to train on a large and high-quality set of training data that is annotated by experts. Besides, active learning (AL) and self-learning can be utilized to reduce the annotation costs. The self-learning method discovers highly reliable instances based on a trained classifier, while AL queries the most informative instances based on active query algorithms. This paper proposes a method that combines AL and self-learning to reduce the labeling effort for the named entity recognition task from tweet streams by using both machine-labeled and manually-labeled data. We employ AL queries based on the diversity of the context and content of instances to select the most informative instances. The conditional random fields are also chosen as an underlying model to train a classifier for selecting highly reliable instances. The experiments using Twitter data show that the proposed method achieves good results in reducing the human labeling effort, and it can significantly improve the performance of the systems.</P>
Anh Linh Dang,Tuyen Quang Nguyen,Tri Thien Cao,Vinh Quang Dinh,Vinh Dinh Nguyen 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10
Traffic detection is a topic of great interest in recent years due to a high demand for better traffic detection systems. Existing traffic detection algorithms work well under ideal driving conditions, however their performance decreases under difficult conditions such as insufficient lighting and illumination. Recently, local patterns have been successfully applied in order to handle complex texture conditions, such as stereo matching, and texture classification. We propose a method that applies Local Tetra Pattern for data preprocessing, so as to improve the performance of deep learning models under said conditions. Our approach achieved better performance than the original raw-models while the changes in inference time are maintained within a negligible interval. By fusing local patterns and raw images, the model gains an acquisition of discriminative information in regions that are highly similar. In challenging conditions, these kinds of information are essential for the model to recover its consciousness of concerned objects which cause many re-cognitional obstructions. Experimental results show a percentage as high as 35.847%, an increase of 12.575% in comparison with the original result on the SKKU data set.
Selective Harmonic Elimination for Cascaded Multilevel Inverters Using Grey Wolf Optimizer Algorithm
Phan Quoc Dzung,Nguyen The Tien,Nguyen Dinh Tuyen,Hong-Hee Lee 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6
In this paper, Grey Wolf Optimizer (GWO) algorithm is applied to determine optimum switching angles for cascaded multilevel inverter of eliminating some high order harmonics while maintaining the required fundamental voltage. As case study in this paper, 11-level and 15-level inverter are considered and the optimum switching angles are calculated off-line to eliminate the 5th, 7th, 11th, 13th harmonics for the 11-level as well as 17th, 19th harmonics for 15-level. The total harmonic distortion is used to estimate the quality of output voltages. The results are shown graphically for better understanding, the mathematical formulations and simulation results will be presented.