A Hydraulic Variable Valve Actuation (HVVA) system is studied in this work, it can continuously adjust engine valve timing and lift at any engine speeds by using a hydraulic actuation system. A detailed co-simulation model is built to reveal relationship between hydraulic pressure, engine valve lift and power consumption, it has taken flow rate, fluid property and pressure drop into consideration. Precision and accuracy of the simulation model are verified by a set of bench test. Coefficient of variation (COV) of engine lift shows that the experiment is repeatable and system robustness is verified through simulation. A modified simulated annealing optimization is conducted to search optimum operation parameters to reduce the HVVA system's power consumption and improve engine's volumetric efficiency (VE) as well as control engine valve seating speed. A pre-selecting criterion and a database retrieve process are added in the algorithm to improve the optimization's efficiency. Optimization shows that optimum pump speed and relief pressure vary from 440 rpm, 32 bar to 2200 rpm, 60 bar when engine speed increases from 500 to 3600 rpm. Corresponding system power consumption rises from 0.07 kW to 0.49 kW, valve lift has a relatively high time-area value (TAV) and an acceptable engine valve seating speed.

在这项工作中研究了液压可变气门致动（HVVA）系统，它可以使用液压致动系统连续调节发动机气门正时并在任何发动机转速下升程。建立了详细的协同仿真模型以揭示液压，发动机气门升程与功率消耗之间的关系，并考虑了流量，流体特性和压降。通过一组基准测试验证了仿真模型的精度和准确性。发动机升程变化系数（COV）表明该实验是可重复的，并且通过仿真验证了系统的鲁棒性。进行了改进的模拟退火优化，以搜索最佳运行参数，以降低HVVA系统的功耗并改善发动机的功率。容积效率（VE）以及控制发动机气门座速。算法中增加了预选择标准和数据库检索过程，以提高优化效率。优化表明，当发动机转速从500 rpm增加到3600 rpm时，最佳泵速度和泄压压力在440 rpm，32 bar至2200 rpm，60 bar之间变化。相应的系统功耗从0.07 kW增加到0.49 kW，气门升程具有相对较高的时域值（TAV）和可接受的发动机气门座速。