Design of advanced HID headlamp system, auto light beam level control and glaring prevention

Abstract

HID lamps on account of their high brightness and efficiency are being adopted as a replacement to the traditional Halogen lamps in automobile lighting systems. However, HID lamp produces more glares compared to Halogen lamps due to sharper cut-off point of its light pattern. The abrupt shift from the dark to bright region of its light pattern is known to cause glare to the oncoming vehicles resulting in temporary discomfort to the oncoming drivers. The present work is related to the solution to overcome the problem of glare caused by the use of HID lamps. Accordingly a system which can control the direction of the light beam from the HID lamp is developed in the current work. Power saving and high power efficiency are also the concerns for this project. In the study of Advanced Headlamp Control System, two types of drive have been examined to control the headlamps that are stepper motor and servo motor. Comparison has been made for the performance and cost. It has been found that the stepper motor provide a higher performance in response time and robustness. Lower cost in overall system is also found. . The Adaptive Front Lighting System (AFS) control is highly related to the distance of the obstacle. Different distance will trigger different operations of the AFS. Simulation of the system by Matlab has been done to examine different cases and conditions. The logic, the input and output of the system have been simulated through software. A number of cases have been done to study the operation condition in details. In automotive system, the voltage conversion from the battery voltage to other unit is important. The present system is to develop a low EMI converter that converts battery voltage 12V to 6V for the control electronics of the proposed Advanced Headlamp Control System. A new switched-capacitor resonant converter is proposed that eliminates the level-shifted gate drive. A circulation inductor is inserted to reduce the shoot-through current. A formulation of the circuit is presented. The method can be extended to other voltage conversion system and other switched-capacitor topologies. Finally, the implementation of the AFS to an electric vehicle is discussed. The design of the EV based on the total running resistance is to use design the motor drive system. The overall vehicle with the installation of the AFS is finally prototyped and demonstrated in an electric vehicle EV4.