Simulation research of the electro-hydraulic control system of CVT metal V-belt´s axial-misalignment

The axial misalignment of steel belt is inevitable outcome of the speed-change way of metal V-belt type CVT. The axial misalignment of steel belt can result in the slipping and addition abrasion between the belt and pulley, and consuming extra energy, which will influence the transmission performance. On the basis of the analysis of the belt misalignment of the metal V-belt CVT, the reason of the belt misalignment has been discussed. In order to control the misalignment, an electro-hydraulic control system has been designed. After deeply analyzing the structure and principle of the electro-hydraulic control system, the belt misalignment control strategy for metal belt CVT has been put forward, and the mathematical model of the electro-hydraulic control system has been established. Being varieties of the working situation of car and the non-linearity of the electro-hydraulic control system, A Fuzzy PID algorithm has been designed. Then the simulation and experiment of the belt misalignment has been conducted, the results showed that the electro-hydraulic control system could remarkably eliminated the belt misalignment, improved the dynamic performance of the metal V-belt CVT, reduced the belt´s abrasion, prolonged the belt´s using-life.