Research On Actuation Mechanism And Control System For Electronic-Hydraulic Variable Valve System

In recent years, the worldwide energy and environment crisis is becoming more and more serious. Internal combustion engines, as the major power take-off for vehicles and ships, takes full responsibilities to reduce harmful emissions and improve energy efficiency. With the international stricter emissions regulations, all automobile manufacturers and engine laboratories are focusing on developing new technologies to meet this criteria. Among them all, the variable valve technology with its significant advantages has been already widely used in vehicles.This paper firstlly introduces the current researches and developing trends on the varible valve system via consulting large amount of relevant literature, In addition, analysis the advantages and shortcomings of different kinds of variable valve mechanisms.Secondly, with the design concept of electronic-hydraulic variable valve mechanism, this paper elaborates the workings and control method of a noval electronic-hydraulic variable valve mechanism by own design. Explore in depth the Peak-Hold control principle of the electronic valve in the driving mechanism. Design the high-frequency drive circuit, and validate the current waveform in the coil aiming at selecting the reasonable PWM control parameters. Moreover dynamic test of the electronic valve is also conducted.Finally, this paper completed the construction and test of sensors, circuits and acquisition equipment in this experimental platform, then completed the measurement and control experiment with the software system developed by Lab VIE W and NI CompactRIO serious data acquisition card.The experimental result shows that this variable valve system achieves the function of variable timing and variable lift, and has a preliminary controllability.