Constant speed cruise control system of the duty ratio control type

摘要

A constant speed cruise control system of duty ratio control type for approximating an actual car speed to a stored target car speed, by on/off control of a control valve of an actuator to adjust the throttle valve opening degree by an output duty ratio D obtained from a control line having a gradient showing a conversion characteristic of car speed and duty ratio. The system has a controller in which a set duty ratio DS corresponding to the target car speed is calculated as SD=SD1+(DM-SD1)/n and the output duty ratio D is calculated as D=GxV+SD where G: gradient of control line V: car speed deviation DM: integrating element responding quickly to duty ratio change SD1: integrating element responding slowly to duty ratio change n: coefficient and the controller corrects to integrate the set duty ratio SD in a direction of approximating the output duty ratio D.