Patent ID: 11939928
Assignee: NISSAN MOTOR CO., LTD.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 0:
1. An EGR control method, the method comprising:
providing an internal combustion engine that comprises an intake pipe, an exhaust pipe, and an EGR passage circulating a part of an exhaust gas of the exhaust pipe into the intake pipe as an EGR gas;
providing an EGR valve in the EGR passage, the EGR valve configured to adjust an EGR gas amount flowing in the EGR passage when the engine is in an EGR region;
providing a differential pressure device in the intake pipe, the differential pressure device configured to adjust a front-and-back differential pressure of the EGR valve;
determining whether or not an exhaust gas pressure of an inlet portion of the EGR passage is equal to or larger than a predetermined pressure;
in response to determining that the exhaust gas pressure is equal to or larger than the predetermined pressure, fully opening the differential pressure device and controlling an opening of the EGR valve according to a target EGR rate that is set to increase as an engine revolution speed and an engine load increase; and
in response to determining that the exhaust gas pressure is less than the predetermined pressure, controlling an opening of the differential pressure device according to an opening degree that is set to increase as the engine revolution speed and the engine load increases and controlling the opening of the EGR valve according to the target EGR rate.