Dynamic Modeling And Simulation On Belt Driven Starter/Generator System

A BSG(belt driven starter/generator) system is a newly emerging front end accessory belt drive system(FEAD), which can achieve the functions of idling stop and braking energy regeneration. This thesis presents dynamic modeling and simulation of a BSG system which was constructed based on an actual FEAD system.A literature review is presented at first, on the FEAD systems, BSG system, and relative researches of dynamic modeling and simulation on either of the two systems.For a specified FEAD system, experiments were carried out to identify belt parameters, including the bending stiffness, the longitudinal stiffness and damping factors, and the contact stiffness of the belt. The FEAD system was then converted into a BSG system by introducing a twin tensioner and a starter/generator, and making necessary change with system configuration. Design parameters are determined accordingly. Principles about the conversion are also discussed, such as system configuration, and selection of the tensioner position and the starter/generator.A dynamic model is established for the constructed BSG system using ADAMS, a widely used commercial software for multi-body dynamic modeling and simulation. After defining working steps, sensors, simulation script and so on, dynamic simulations were successfully implemented on the model for the dynamic responses of the system in a whole operating loop, which consists of a motor cranking stage, an engine cranking and a transition stage between the two ones. Belt vibration, tension variation, tensioner behavior are thus obtained, and the impact of the tensioner parameters is discussed. Observations are then made from those results and discussions, which are helpful to the design of a BSG system.