在汽油机中配置可变气门机构会改变因驱动气门机构而消耗的能量.为了研究全可变气门机构汽油机气门机构消耗的能量,在实验台架上测取了可变气门正时(VVT)、可变气门升程(VVL)执行器消耗的电能以及驱动气门机构的扭矩,并计算了驱动功率.实验结果表明,VVT及WL电子执行器消耗的电能较小,气门机构驱动消耗机械能量相对较大.发动机转速为1 500 r/min,机油温度为60℃时,气门升程从9 mm下降到1 mm,气门机构驱动功率从700W下降到50W.负气门重叠角负荷控制在发动机转速1 500 r/min,平均有效压力0.2 MPa时最高可节油18.8%,进排气门最大升程均较小是其节油的重要原因.
Application of the variable valve actuation (VVA) system is an effective way to reduce the gasoline engine fuel consumption.Energy consumption of valve train system will be changed after VVA system applied on the gasoline engine.Aim of the study is to understanding the energy consumption of VVA system which is equipped on the gasoline engine.Experimental data on the electronic power consumption of both the electromagnetic valve for variable valve timing (VVT) system and DC motor for variable valve lift (VVL) system were analyzed.The driven power of valve train system was measured and analyzed.Results show that the energy consumption of both the electromagnetic valve and DC motor is quite small compared to the driven power of the valve train system.At 1 500 r/min engine speed and 60 ℃ oil temperature,the decrease of valve lift from 9 mm to 1 mm has led to valve train energy consumption reduction from 700 W to 50 W.Engine load controlled by negative valve overlap can reduce fuel consumption by 18.8% at 1 500 r/min and 0.2 MPa BMEP(brake mean effective pressure).Small intake and exhaust valve lifts are key reason of reducing fuel consumption.