應用功能動力圖論方法於車輛扭力導引系統之設計與分析

Abstract

本研究探討扭力導引系統應用於車輛動態控制時之系統特性，並搜尋可能的系統構型作為未來系統發展之參考依據。隨著車輛安全性與操控性的要求日益提高，各種車輛動態控制的技術被廣泛的討論與應用。近年來扭力導引系統的開發日漸受到車輛產業的重視，該系統可藉由導引引擎扭力至特定車輪進行驅動力的分配，提升車輛的動態表現達到更安全更靈活的駕駛環境。為了使扭力導引系統的研究更為系統化且有效，本論文提出一套整合式的動力系統圖論方法並將其命名為「功能動力圖」(FPG)。該圖論方法可以圖形符號簡潔且明確的表示動力系統的架構，並可藉由該圖為基礎所發展之分析與設計方法對扭力導引系統進行一系列的開發流程。本研究首先應用功能動力圖分析方法探討現有扭力導引系統的機構組成、自由度、系統功能及系統動態方程式的推導，並應用功能動力圖設計方法進行系統合成討論可能的系統構型，建立系統圖集。接著針對雙無段變速系統(DCVT)進行動態模擬以評估其防滑差速以及扭力導引功能，並針對各式雙無段變速系統的行車特性進行了比較與討論。最後以實驗初步驗證其模擬結果的正確性。本論文主要貢獻包含兩部分:1)發展功能動力圖論方法並成功應用於混合動力系統、車輛傳動系統、自排變速箱系統及扭力導引系統之設計與分析;2)針對雙無段變速系統(DCVT)進行研究並了解其扭力導引特性。

The purpose of this study is to understand the characteristics of torque vectoring systems for vehicle dynamic control applications, and to make design syntheses of new system configurations for future system development. As the requirement of vehicle safety and drivability arises, varied vehicle dynamic control technologies have been widely discussed and applied. In recent years, torque vectoring system draws more attention in automotive industry since the system is able to transfer more driving torque to certain wheel to make a traction distribution so that better vehicle safety and agility can be achieved. In order to make the research of torque vectoring systems more systematic and efficient, an integrated graph-based powertrain design and analysis methodology known as 'Function Power Graph' (FPG) is proposed in this dissertation. The FPG is a symbolic graph which can present the configuration of a powertrain concisely and precisely. With the analysis and design techniques developed based on the FPG, the development process of torque vectoring systems can be performed. In this dissertation, the system configuration, degree of freedom, system function and the dynamic equation of the torque vectoring systems are investigated with the FPG analysis techniques. New possible system configurations are found with the FPG design techniques. Then, the limited-slip function and torque vectoring effect of the dual continuously variable transmission (DCVT) are evaluated with dynamic analysis. And the driving property of different DCVT systems are compared and discussed. At last, a practical experiment is performed and the correspondence to the simulation results is preliminarily approved. The main accomplishment of this research has two major parts: 1) The development of the FPG methodology which has been successfully applied to the design and analysis of hybrid systems, vehicle drivelines, automatic transmissions, and torque vectoring systems; 2) The investigation of the DCVT systems to understand the torque vectoring characteristics of the systems.