Study On Vehicle's Hydraulic Active Suspension Controlled By High Speed ON/OFF Solenoid With Fuzzy Control Method

With the economy development and social progress, people need better quality about the vehicle, such as comfort, riding stability. Traditional passive suspension cannot meet the trend gradually. Active suspension is a new suspension arisen in recent years, it has power device and it can produce a control force to restrain the outside disturbance actively and timely. Much research work has been done without a satisfying solution, although some vehicle with active suspension has produced, which are too expensive to produce in large scale.So, study on active suspension with high stability and good isolation performance is still belonging to advanced study. It has a bright future and practical values. This research was sponsored by Ministry of Education. In this dissertation, an active hydraulic vibration isolation system employing High speed ON/OFF solenoid valve was proposed, fuzzy control method and PWM technique were used in this system. It was proved by experiment that the proposed active suspension system was correct and fuzzy control method was effective. It also indicates that the proposed active suspension was an ideal active suspension device with low price and high quality. It can be used as a teaching experiment for college student majored in electromechanical with practical value.The major contents of this dissertation as following:1 A quarter vehicle's mathematic model was established for the active suspension system.2 A fuzzy controller was designed for the active suspension with fuzzy control method.3 Simulation study on the fuzzy controller's parameter and control performance were done in this dissertation.4 An experiment device was designed for the proposed active suspension system.5 Experiment study of the active suspension system's isolation performance was carried out under variable working conditions.