Design And Control Analysis Of HSV Hydraulic System In CVT

Matching the usage power characteristic of engine with its ideal characteristic as soon as possible, The advanced technology of Continuously Variable Transmission (CVT), guarantee the low oil consumption and low exhaust emission, is the main develop orientation of automobile. Electronic Continuously Variable Transmission (ECVT) is the improved type of CVT which most broadly used now.With the development of the industrial automation, a combination of Hydraulic technology, computer technology and electronic technology has been an inevitable trend. So it caused the appearance and development of the digital hydraulic technology. High speed on/off valve (HSV) is a kind of new valve, Simple structure, low cost, non-sensitive to contamination and no need for D/A converter with the computer make it possible for widely used in the industrial.This paper introduced the CVT's profile and the structure and principles of CVT GL160C, especially the composition and theory of the hydraulic sysyem. Based on the previous research and six months'tests in the factory, the author designed PWM control hydraulic system, modeled and simulated the system with Fuzzy-PID control method.The simulation showed that the system's response is rapid, the control is stable and precision. Contrasting with the simulation results of the proportional hydraulic system shows that the high-speed on/off valve hydraulic control system and the fuzzy-PID control method is superior.