汽油机可控机械增压系统的研究

摘要

为有效提高机械增压发动机低负荷的经济性和高负荷的动力性,笔者研究了一种可控式机械增压模式,在直喷汽油机曲轴所连皮带轮与机械增压器之间添加一电磁离合器,通过电磁离合器的控制及所设计的旁通阀调压系统实现机械增压器在不同负荷下的的通断要求.通过GT-power软件模拟计算结果表明,该控制策略的机械增压发动机油耗曲线的最佳经济区更广阔,万有特性曲线扭矩有明显提高,因此可使发动机运行达到低负荷保油耗,高负荷提扭矩的目标,并且可实现发动机由低负荷向高负荷的平稳过渡.%To balance the economy in low load and dynamic property in high load effectively,this paper studies a controllable supercharged mode which adds an electromagnetic clutch between belt pulley which connected crankshaft and mechanical pressurizer in a GDI engine.Through the electromagnetic clutch control and the design of the bypass valve pressure regulating system,the requirement of on-off on mechanical supercharger was achieved in different loads.The simulation and calculation by GT-power software show that the best economic zone at fuel consumption curve of mechanical pressurization engine using the control strategy is much broader,and the torque in universal performance curve is improved obviously which can make the engine reach the target of reducing fuel consumption in low load and improving torque in high load,also it can realize smooth transition from low load to high load.