公开(公告)号：EP2065587A2

公开(公告)日：2009-06-03

申请号：EP08020808.5

申请日：2008-12-01

申请人： Hitachi Ltd. and Hitachi-LG Data Storage, Inc.

发明人： Yamaoka, Shiro ,  Sukegawa, Yoshihiro ,  Tokuyasu, Noboru ,  Hoshika, Hiroaki ,  Kashio, Kaori

IPC分类号： F02D21/08 ,  F02D41/14 ,  F02D41/22

CPC分类号： F02D41/0002 ,  F02D41/0072 ,  F02D41/18 ,  F02D41/222 ,  F02D41/3035 ,  F02D41/3076 ,  F02D2041/0075 ,  F02D2200/0406 ,  F02D2400/08 ,  F02M26/05 ,  F02M26/06 ,  F02M26/28 ,  F02M26/47 ,  Y02T10/42 ,  Y02T10/47

摘要： An engine that re-circulates its exhaust gas suffers decreased accuracy in estimating an EGR rate real-time especially while the operating state of the engine 19 is in a transitional state, which often results in torque fluctuations and deteriorated exhaust gas.
A sensor 12 for directly detecting an EGR flow rate is disposed in an EGR path 9. An EGR rate and in-cylinder oxygen concentration are calculated from the output value of that sensor 12. In addition, when this EGR rate calculation method is used, the calculation is properly switched between a steady operation state characterized by a low load and small rotational fluctuations and a transitional operating state including the acceleration and deceleration. This makes it possible to correctly estimate the EGR rate and the in-cylinder oxygen concentration under a wide range of engine operation conditions, and thereby to avoid the fluctuation of torque and the deterioration of exhaust gas.

摘要翻译： 特别是在发动机19的运转状态处于过渡状态时，特别是在经常导致转矩波动和废气劣化的情况下，再次循环排气的发动机的EGR率实时估计的精度降低。 用于直接检测EGR流量的传感器12设置在EGR通路9中。根据该传感器12的输出值计算EGR率和缸内氧浓度。此外，当使用该EGR率计算方法时， 该计算在由低负载和小的旋转波动表征的稳定运行状态和包括加速和减速的过渡运行状态下适当地切换。 由此，能够在大范围的发动机运转条件下正确地估计EGR率和缸内氧浓度，能够避免转矩波动和排气恶化。