本研究的主題為探討電動巴士在不同的駕駛情況下，所產生的車身動態行為。在現今的市場上，大部分的相關研究領域為能源控管，極少針對車身的動態之控制做探討。故本研究以最佳化控制理論為基礎，並考慮縱向速度為時變，以合理的三自由度車輛數學模型設計SDLQ (State Dependent Linear Quadratic)主動式安全控制器，藉由後輪轉向、偏航力矩及四輪驅動控制命令的輸入，來提高行車穩定性並改善巴士的車身橫向動態，再以車輛模擬軟體TruckSim®進行控制器的驗證，以提供後續電動實車相關研究之使用。

In the electronic vehicle industry, the majority of the research focuses on enhancing the battery performance; therefore, there is a lack of research in improving the vehicle’s dynamic performance. This thesis investigates the feasibility of four wheel steering for an electric bus under various driving conditions. A linearized 3 DOF model was used to model the electric bus. As the system matrix of the electric bus varies depending on the longitudinal speed, a state dependent linear quadratic (SDLQ) controller was used to control the four wheels of the electric bus. The controller requires three inputs: front wheel angle, lateral velocity, and yaw rate. The controller then outputs the required rear wheel angle and the yaw moment that will improve the driving stability and the lateral dynamics of the electric bus. TruckSim® was then later used to test the performance of the controller. It is expected that the results of this thesis will provide a foundation for EV bus related research.

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