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Drive System of Electrical Lighter Vehicle with Brushless DC MachineLu, Wei-i 05 February 2010 (has links)
A drive system of the electrical lighter vehicle with the brushless DC machine is developed in the thesis. The system consists of a control unit based on a digital signal processor (DSP) and a drive module which combines a drive circuit, a brushless DC machine, and associated wheels. The motive power is delivered directly to the wheels without a power transmission system. The driving comments and the monitored signals between the modules and the control unit are communicated by the Controller Area Network (CAN) Bus. Each module can be controlled independently. By modifying the software of the system, the proposed drive system can be implemented in various electrical vehicles without changing circuit design. The developed system can be operated at forward, backward, and rotating motions. By limiting the armature current, the vehicle can be operated under the power saving mode. During the regenerative braking, the battery set is charged by the regenerative current. The experimental results show that the highest efficiency of the machine is 80 % with the motoring operation.
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Simulation and Economic Analysis of a Hybrid Wind Diesel System for Remote Area Power SupplyAbdullah, Jalal 06 September 2010 (has links)
The Kingdom of Saudi Arabia has an area of 1.69 million square kilometers. It is the biggest oil producers in the world, and the electricity industry relies heavily on oil. The annually growth request for electricity is around 5%. The price of electricity will be expensive in the next 30 years and there could be a shortage of electricity supply. It is better to use alternative forms of energy to prolong the life of the oil industry in Saudi Arabia. To reduce dependence on oil, the Kingdom of Saudi Arabia is considering using alternative sources of energy including solar energy and energy wind. Since the wind speed is around 10m/s and in the summer it is full of sunshine; therefore, the renewable energy should play a more important role in future electric power supply of the Kingdom of Saudi Arabia. A hybrid system is proposed in this thesis to study the possible power supply system in the remote areas. Wind information in Dhahran is used in simulations in order to make sure that the system is reliable and appropriate to be used in the remote areas of the country. Economic analysis is also conducted to compare the cost of the hybrid system with that of a 200 km transmission line connected from existing service area.
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Hybrid Fuzzy Kalman Filter for Workload Prediction of 3D Graphic SystemKe, Bao-chen 28 July 2011 (has links)
In modern life, 3D graphics system is widely applied to portable product like Notebook, PDA and smart phone. Unlike desktop system, the capacity of batteries of these embedded systems is finite. Furthermore, rapid improvement of IC process leads to quick growth in the transistor count of a chip. According to above-mentioned reason and the complex computation of 3D graphics system, the power consumption will be very large. To efficiently lengthen the lifetime of battery, power management is an indispensable technique.
Dynamic voltage and frequency scaling (DVFS) is one of the popular power management policy. In the scheme of DVFS, an accurate workload predictor is needed to predict the workload of every frame. According to these predictions a specific voltage and frequency level is applied to each frame of the 3D graphics system. The number of the voltage/frequency levels and the voltage/frequency of each level are fixed, the voltage/frequency table is decided according to the application of power management. Whenever the workload predictor completes the workload prediction of next frame, the voltage/frequency level of next frame will be found by looking up the voltage/frequency table.
In this thesis, we propose a power management scheme with a framework composed of mainly Kalman filter and an auxiliary fuzzy controller to predict the workload of next frame. This scheme amends the shortcomings of traditional Kalman filter that needs to know the system features beforehand. And we propose a brand new concept named ¡¨delayed display¡¨ to massively reduce the miss rate of prediction without changing the framework of predictor.
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Design of Phasor Measurement Unit and Its Application to Phasing Recognition of Distribution EquipmentsWu, Mei-Ching 11 July 2012 (has links)
Taipower Company has already completed the installation of the Outage Management System (OMS) in all service districts. The attributes of all distribution equipments and customers have been included in the computerized mapping system. However, the phasing attributes of distribution transformers are not very accurate in the database because they are very difficult to be identified for the distribution systems. The phase information of transformers in the OMS database is often inconsistent with the actual service phase, which deteriorates the performance of distribution system analysis, planning, and operation of Taipower distribution systems. The objective of this thesis is to develop an innovative Phasor Measurement Unit (PMU) to support the phasing identification of distribution transformers in a very effective way. The proposed PMU is used to measure the low voltage signal at the secondary side of transformers to prevent the survey personnel from safety problem. With the measured phases information of distribution transformers stored in the embedded system, the attributes of transformer phases in OMS can be updated to improve the accuracy of database. For the underground distribution systems, it is very difficult to receive the 1PPS signal of GPS system for timing synchronous to support the proposed transformer phasing measurement because all transformers are located at the building basement. This thesis proposes a timing synchronous module by using the Temperature Compensated Crystal Oscillator, TCXO to maintain the timing accuracy with high precision. Before executing the phasing measurement, this module is calibrated using the GPS 1PPS signal with fuzzy control calibration algorithm. It is found that the proposed PMU module can maintain the timing synchronous with 6˚, during two hours time period which will support the transformer phasing measurement by providing the reference timing synchronous even without the GPS 1PPS signal.
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The Distributed Control Program Generator of Microprocessor-based EnvironmentHuang, Szu-kai 30 July 2012 (has links)
In the field of the industrial automatic control, both MCU (Micro Control Unit) and PLC (Programmable Logic Controller) are widely being used in DCS (Distributed Control System). Since MCU can provide complex process scheduling, accurate timing control and PLC has the advantages of easy programming and maintaining. However, the control programs of the MCU are hard to design and maintain. Identically, the poor signal processing ability, high cost and the restrictive functions are the major defects of PLC.
In order to solve the drawbacks described above in MCU and PLC, we provide a PLC-like interface for users to access the devices and set the registers of MCU. Likewise, designers can develop the control program via Event-table-driven modules. On the other hand, our main goal of DCS is to quickly construct the distributed N level network topology based on Modbus protocol, which is efficient and reliable. Therefore, we bring up a data collection method and Slave-to-Slave strategy so as to distribute the master loading, reduce the package transmission times and improve the real-time latency.
In conclusion, our research results not only congregate the benefits of MCU and PLC but provide an environment to quickly construct and conveniently monitor DCS, which meets the time-to-market demands.
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Fixed-Order Optimal Controller Design of an ANC HeadphoneWu, Ting-Yu 29 August 2012 (has links)
This thesis presents a feedback design for an active noise cancellation (ANC) headphone. The designed ANC headphone consists of an analog controller, an audio power amplifier, a headphone speaker, a mini microphone, and a microphone amplifier, which constitute a feedback loop. The controller design follows the method of feedback sensitivity shaping with degree constraint introduced by R. Nagamune and A. Blomqvist in 2005. The advantage of this method is that it eliminates the needs for choosing an analytic weighting function and performing model reduction to yield a lower-order controller, as commonly required in conventional H2/H¡Û optimizations. A fifth-order analog controller for the ANC headphone is designed. The experimental result shows a maximum acoustic noise reduction of 19.7 dB near 200 Hz and an overall noise reduction of more than 10 dB in the control frequency band from 107 Hz to 523 Hz. Moreover, the out-of-band noise amplification is limited to a barely noticeable level of 4.26 dB.
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Design of Model Reference Adaptive Tracking Controllers for Mismatch Perturbed Nonlinear Systems with Nonlinear InputsSu, Tai-Ming 03 May 2004 (has links)
A simple design methodology of optimal model reference adaptive control (OMRAC) scheme with perturbation estimation for solving robust tracking problems is proposed in this thesis. The plant to be controlled belongs to a class of MIMO perturbed dynamic systems with input nonlinearity and time varying delay. The proposed robust tracking controller with a perturbation estimation scheme embedded is designed by using Lyapunov stability theorem. The control scheme contains three types of controllers. The first one is a linear feedback optimal controller, which is designed under the condition that no perturbation exists. The second one is an adaptive controller, it is used for adapting the unknown upper bound of perturbation estimation error. The third one is the perturbation estimation mechanism. The property of uniformly ultimately boundness is proved under the proposed control scheme, and the effects of each design parameter on the dynamic performance is also analyzed. An example is demonstrated for showing the feasibility of the proposed control scheme.
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Flight Control Of A Tilt Duct Uav With Emphasis On The Over Actuated Transition Flight PhaseUnlu, Tugba 01 October 2009 (has links) (PDF)
In the thesis, automatic flight control system is designed for Tilt Duct Unmanned Aerial Vehicle (UAV). The vehicle is a Vertical Take-Off Landing (VTOL) type with two symmetric
rotors on the wings, one aft rotor on the aft body. It behaves like a helicopter but with higher speeds in forward flight. Transition flight of the aircraft from hover to cruise or take-off to forward flight is the primary concern of the thesis study with the nonlinearities and instabilities encountered, together with the over-actuated controls in this mode. A nonlinear simulation code is developed including nonlinear equations of motion together with the nonlinear aerodynamics,
environmental eects, and rotor dynamics. Trim and linearization codes are also developed. Trim conditions for the transition flight phase are calculated for two different
transition scenarios. Linear controllers are developed and nonlinear controller is designed for the transition mode. Nonlinear controller uses the state dependent Ricatti equation SDRE approach by using extended linearization. Two loop approach is used in order to increase controllability. In the inner loop, attitude rates are fed back and SDRE approach is used to calculate the feedback gain matrix online. In the outer loop, vehicle attitude is controlled using the eigenvalue assignment. Blended inverse algorithm based control allocation method is used in control of the over-actuated transition phase. This algorithm is shown to be quite effective among different methods in not only generating necessary forces needed for the control, but also allocating with more control authority on the desired actuator.
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Landing Autopilot Design For An UavHankoylu, Merve 01 February 2011 (has links) (PDF)
In this thesis, a landing autopilot for an UAV (IAI Pioneer RQ-2) is designed
based on a nonlinear MATLAB model implemented with MATLAB/Simulink. In
order to control the movement of the UAV at lateral and longitudinal axes, a
speed, an altitude, a heading angle (direction) and a yaw rate controllers are
designed. Controller design procedure is started with determination of different
trim points of the aircraft. Next, the corresponding initial states and initial
inputs are obtained. The model is linearized about those trim points and the
gain values are determined. The resultant gain scheduled controller is used on
the non-linear model.
The response of the aircraft to these controllers is tested in a constrained
landing area that is constructed with respect to applicable aviation regulations.
The aircraft position is investigated whether it is inside or outside of this safe
landing area. If it is inside, an optimized landing path set is obtained. The
steepest descent method is used for multidimensional search and parabolic fit
method is used for one dimensional search (as line search) in the optimization
phase.
In case it is outside the defined landing area a special algorithm which takes
the aircraft into the desired region is applied. In addition, the area is allowed to
move as much as possible depending on the situation with special regards to
the length of the runway. Also a lateral position controller is designed in order
to provide the reach of the aircraft to the main landing path.
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Controller Design And Simulation For A Helicopter During Target EngagementAvcioglu, Sevil 01 December 2011 (has links) (PDF)
The aim of this thesis is to design a controller for an unmanned helicopter to perform target engagement. This mission is briefly defined as / the helicopter flies to a firing point under the commands of a trajectory controller, and then it is aligned to the target with attitude control. After weapon firing, the helicopter initiates a return maneuver under again the commands of the trajectory controller. This mission where the continuous systems and discrete guidance decisions are to be executed in coherence can be studied as a hybrid control problem. One hybrid control approach which is used in this study is the representation based on two motion primitives: trim trajectories and maneuvers. To obtain the desired trim trajectories and the maneuvers, a dynamic inversion based controller is developed. The controller has two loops: the inner loop which controls the helicopter attitudes and the outer loop which controls the helicopter trajectory. A guidance algorithm is developed which enables the controller to switch from the inner loop to the outer loop or vice versa. Simulations are generated to test the controller performance.
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