System and Method for Exhaust Gas Recirculation Flow Correction Using Temperature Measurements

摘要

An exhaust gas recirculation (EGR) flow correction system and method are disclosed for an engine air system with air and EGR inputs to a mixer. The system includes three temperature sensors to measure temperatures of the air input, EGR input, and mixer output; and an air system model computing EGR flow corrections using the three temperatures. Air system can include intake manifold, charge air cooler (CAC), air throttle, EGR cooler and EGR valve, with first sensor between CAC and air throttle, second sensor between EGR cooler and EGR valve, third sensor in intake manifold. Air system model can estimate mass flows through air and EGR inputs, estimate intake manifold temperature at third sensor, estimate intake manifold temperature error, and compute EGR corrections based on temperature error. Air system model can estimate CAC and EGR cooler outlet temperatures, and mixer input temperature.

主权项

1. An exhaust gas recirculation (EGR) flow correction method for an engine air system comprising an air input, an EGR input and a mixer; the method comprising:
measuring an air temperature of air passing through the air input using a first temperature sensor; measuring an EGR temperature of EGR gases passing through the EGR input using a second temperature sensor; measuring a mixed gas temperature of mixed gases after passing through the mixer using a third temperature sensor, the mixed gas being a mixture of the air passing through the air input and the EGR gases passing through the EGR input; modeling the engine air system using an engine air system model; computing an EGR flow correction using the air temperature, the exhaust gas temperature and the mixed gas temperature; and using the EGR flow correction in the engine air system model.