http://thuvienso.dut.udn.vn/handle/DUT/9748 2026-04-07T08:00:07Z 2026-04-07T08:00:07Z Đoàn, Anh Tuấn http://thuvienso.dut.udn.vn/handle/DUT/9924 2025-10-08T18:07:29Z 2007-01-01T00:00:00Z

Title: Các quá trình quá độ điện từ cao tần trong truyền động điện sử dụng động cơ không đồng bộ tuyến tính phẳng cấp nguồn từ bộ biến đổi tần số điều chế độ rộng xung Authors: Đoàn, Anh Tuấn Abstract: Проблема высокочастотных электромагнитных процессов B электрических сетях и установках является частью проблемы электромагнитной значение существенно возросло в последние 10-15 лет в связи с развитием новых технологий, связанных с применением полупроводниковой техники. Рост негативных последствий от ложных срабатываний систем автоматики совместимости (ЭМС) электрооборудования. Ее и преждевременного выхода из строя электрооборудования вызвал появление работ [1, 87, 88] и публикаций [7, 23, 78, 89, 112, 113] по высшим гармоникам в электрических системах. Description: 167 страница 621.313. ĐO-T

2007-01-01T00:00:00Z Võ, Văn Phương http://thuvienso.dut.udn.vn/handle/DUT/1928 2025-08-18T11:51:27Z 2023-01-01T00:00:00Z

Title: Nghiên cứu, đánh giá ảnh hưởng của nguồn điện gió công suất lớn đến hệ thống điện Authors: Võ, Văn Phương Abstract: Luận án nghiên cứu về nguồn điện gió và một số dạng năng lượng tái tạo có liên quan; nghiên cứu các phần mềm và ngôn ngữ lập trình Matlab, Python phục vụ mô phỏng, tính toán; các vấn đề liên quan đến công tác dự báo công suất phát nguồn điện gió, vấn đề quy hoạch và vấn đề tính toán tối ưu nguồn điện gió. Description: Tài liệu nội sinh

2023-01-01T00:00:00Z Nguyen, Ngoc Tan http://thuvienso.dut.udn.vn/handle/DUT/1927 2025-08-18T11:51:27Z 2018-01-01T00:00:00Z

Title: Ultrathin conducting polymer transducers: Fabrication, characterization, and modeling Authors: Nguyen, Ngoc Tan Abstract: Recently, ultrathin poly (3,4-ethylenedioxythiophene) (PEDOT) – based ionic actuators have overcome some initial obstacles to increase the potential for applications in microfabricated devices. While microfabrication processing of trilayer actuators that involve no manual handling has been demonstrated, their mechanical performances remain limited for practical applications. The goal of this thesis is to optimize the transducers in thin films fabrication by micro technologies, fully characterize the electrochemomechanical properties of the resulting trilayers, and develop a model to simulate their bidirectional electromechanical ability (actuation and sensing). At first, ultrathin PEDOT-based trilayer actuators are fabricated via the vapor phase polymerization of 3,4-ethylenedioxythiophene combining with the layer by layer synthesis process. This constitutes the first full characterization of ionic PEDOT-based microactuators operating in air of such a small thickness (17 µm) having bending deformation and output force generation of 1% and 12 µN respectively. Secondly, electrical, electrochemical and mechanical properties of the resulting microactuators have been thoroughly studied. Non-linear characterization was extended to volumetric capacitance dependence on voltage window. Damping coefficient was characterized for the first time. Thirdly, a nonlinear multi-physics model was proposed as a method of simulating actuator and sensor responses in trilayers, represented using a Bond Graph formalism, and was able to implement all of the characterized parameters. The concordance between the simulations and the measurements confirmed the accuracy of the model in predicting the non-linear dynamic electrochemical and mechanical response of the actuators. In addition, the information extracted from the model also provided an insight into the critical parameters of the actuators and how they affect the actuator efficiency, as well as the energy distribution. These are the key parameters for designing, optimizing, and controlling the actuation behavior of a trilayer actuator. Finally, a nouveau bidirectional electromechanical linear model was introduced to simulate the sensing ability of the trilayer transducer. The simulation coherently matches the experimental results in both frequency and time domains of a sinusoidal input displacement. The resulting actuators and the proposed models are promising for designing, optimizing, and controlling of the future soft microsystem devices where the use of polymer actuators should be essential. Description: Doctoral thesis. Major: Electrical and computer engineering; 182 pages

2018-01-01T00:00:00Z Phan, Dinh Chung http://thuvienso.dut.udn.vn/handle/DUT/1926 2025-08-18T11:51:27Z 2017-01-06T00:00:00Z

Title: Maximum Power Point Tracking of a DFIG Wind Turbine System Authors: Phan, Dinh Chung Abstract: Doubly-fed induction generator (DFIG) has been used popularly in variable speed wind turbines because the DFIG wind turbine uses a small back-to-back converter to interface to the connected grid, about 30% comparing to the wind turbine’s capacity, and provides a control ability as good as a variable speed wind turbine using a generator with a full converter. The most important purpose of a variable speed wind turbine or a DFIG wind turbine, in general, is to utilize fully wind energy for electric generation. To meet this objective, several publications provided different methods. Generally, the previously proposed schemes can be listed into two groups such as wind speed-based method and wind speed sensorless one. With the first group, the wind turbine can give a good performance in tracking maximum power point but it requires a precise and instantaneous wind speed measurement; this requirement hardly achieve in practice. With methods in the second group, an anemometer does not require but the wind turbine using these methods cannot track maximum power point efficiently under varying wind conditions. In this dissertation, I proposed two methods and control laws for obtaining maximum energy output of Doubly-fed induction generator wind turbine. The first method aims to improve the conventional MPPT curve method while the second one is based on an adaptive MPPT method. Both methods do not require any information of wind data or wind sensor. Comparing to the first scheme, the second method does not require the precise parameters of the wind turbine. The maximum power point tracking (MPPT) ability of these proposed methods are theoretically proven under some certain assumptions. In particular, DFIG state-space models are derived and control techniques based on the Lyapunov function are adopted to derive the control methods corresponding to the proposed maximum power point tracking schemes. The quality of the proposed methods is verified by the numerical simulation of a 1.5-MW DFIG wind turbine with the different scenario of wind velocity. The simulation results show that the wind turbine implemented with the proposed maximum power point tracking methods and control laws can track the optimal operation point more properly comparing to the wind turbine using the conventional MPPT-curve method. The power coefficient of the wind turbine using the proposed methods can retain its maximum value promptly under a drammactical change in wind velocity while this cannot achieve in the wind turbine using the conventional MPPT-curve. Furthermore, the energy output of the DFIG wind turbine using the proposed methods is higher compared to the conventional MPPT-curve method under the same conditions. Description: Doctoral thesis. Major: Electrical and computer engineering; 73 pages

2017-01-06T00:00:00Z