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By utilizing the electric motor as the propulsion system, the electric vehicle (EV) establishes a new bridge between renewable energies and our daily life, which meanwhile has to face with a brand new technical issue, namely the energy management and conversion. Then, the performance of energy conversion systems has become a new evaluation criteria for EVs. Accordingly, this study works on the analysis and control of the EV energy conversion system, including the secure charging system via wireless power transmission (WPT), advanced driving control via electric propulsion system, and bidirectional power interface via electromagnetic interference (EMI) mitigation technique. First, this study proposes a novel energy encryption algorithm for WPT systems. In the presented scheme, the energy can be encrypted by chaotically regulating the frequency of the power source based on the unpredictable security key. The authorized receptor can effectively receive the energy by simultaneously adjusting the circuit to decoding the encrypted energy based on the acquired security key, while the unauthorized receptor cannot obtain the energy without knowledge of the security key. In this study, both simulation and experimental results are provided to verify the feasibility of the proposed secure WPT system. Subsequently, this study proposes a new dynamic model of EV powering steering systems, by synthetically taking into account characteristics of the electric propulsion motor, driver’s operation, and uncertain disturbances caused by irregularities of the road surface. By using various nonlinear analysis methods, the unstable chaotic behaviors can be revealed in the power steering system, especially when the vehicle turns a concern at a high speed. Additionally, a new control algorithm is designed and implemented to stabilize the EV power steering system, and corresponding validity is also mathematically proved in this study. Thirdly, an integrated driving control system is designed based on the aforementioned dynamic analysis, which is used to enhance the stability and maneuverability performances of four-in-wheel independently-driven (4WID) EVs. By adopting the supervisor-actuator structure, the proposed driving control scheme not only effectively improves the performance of tracking reference paths, but also optimally distribute the desired yaw moment to each in-wheel motor. In this study, the mathematical proof and the simulation are both conducted to demonstrate the feasibility of the proposed integrated driving control strategy. Lastly, this study also works on the EMI issue caused by switch-mode energy conversion devices for EVs. In this section, a new pulse-width-modulation (PWM) method is designed by utilizing the random-like sequence, aiming to suppress the conducted peaky EMI over the whole power spectrum, thereby ensuring the working performance for electronic instruments in EVs. For demonstrating the effectiveness of the proposed soft-chaoizing scheme, this study takes two exemplifications such as the electric propulsion drive system and the bidirectional power interface for vehicle-to-grid (V2G) systems. / published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

No description available.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 220-227).

ATP synthase (F_1 F_O-ATPase) is an essential enzyme for life. Powered by an electrochemical proton gradient, it catalyzes ADP and phosphate into ATP. The F_1-subunit of ATP synthase is called F_1-ATPase as it also independently catalyzes the reverse reaction in absence of F_O-part. The nearly 100% energy conversion efficiency of the molecular motor has attracted the attention of many physicists and biologists to explore the underlying thermodynamics. Recently, a new nonequilibrium equality derived by Harada and Sasa (Harada & Sasa, 2005) was applied to the experimental time series data on F_1-ATPase to extract heat flow to the environment. A phenomenological model for rotary motion was proposed and shown to reproduce key experimental features. Interested in the high efficiency of F_1-ATPase and the good performance of the corresponding model, we carried out a detailed computational study of the model to understand its behavior in a broader range of parameter values. We solved the model using a modified Gillespie algorithm for stochastic simulation and by integrating the Fokker-Planck equation. Various physical properties of the model, such as the relation between rotational velocity and parameters characterizing angular dependence (q) and ATP switching rates (W), the relation between two kinds of dissipation and rotational velocity, the negative heat flow from environment to system through ATP binding etc. are analyzed in detail. Importantly, we modified the driving potential to investigate the factors affecting the efficiency. Additionally, we found some inconsistences between properties of this model and previous studies and we could unify them by some adjustments, which may be useful for constructing more precise models in the future.

The induced potential difference across a standing shock front can be used to drive electric current through external loads. Such a "standing shock generator" presents an alternative scheme to the MHD generator for direct conversion of energy from high temperature supersonic flows. We make use of the supersonic flow behind a free running shock in a shock tube and let the flow impinge onto a conical obstacle mounted in the middle of the tube to create a standing shock. This cone has a conducting surface which acts as the anode. The cathode is mounted flush with the shock tube wall at a position upstream of the standing shock. By varying the load resistance, we have obtained current-voltage characteristics for the standing shock generator. These characteristics are families of parallel straight lines similar to the characteristics of a battery. The open-circuit voltage is found to depend on the standing shock potential and the work functions of the electrodes. The internal resistance (equivalent to the slope of the characteristic) is found to be dominated by the plasma-wall interaction at the surface boundary layers. The maximum current collected by the electrode is therefore limited to its ion saturation current. A typical result of the standing shock generator in our experiment gives 1 volt with 0.5.amp for the. 30X10⁻⁶ sec test time duration. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

No description available.

Thesis (Ph. D.)--Washington State University, May 2009. / Title from PDF title page (viewed on Apr. 2, 2009). "School of Mechanical and Materials Engineering." Includes bibliographical references.

Thesis (Ph. D.)--Washington State University, May 2009. / Title from PDF title page (viewed on Apr. 19, 2010). "College of Engineering and Architecture." Includes bibliographical references (p. 113-116).

Thesis (Ph. D.)--University of Illinois, 1967. / Includes bibliographical references (leaves 161-164).