Compensating for sensor location in an internal combustion engine mixed fuel supply system

摘要

The distance of the blend or composition sensor 41 from the injectors 14 in the returnless system restricts the use of the sensor directly for an instantaneous indication of the blend ratio of fuels at the injectors, particularly under transient engine conditions. To compensate for this, an estimate of the gradient of the blend ratio in the line 40 is continuously made in terms of a blend ratio value for each of a stack of N notional cells of equal fuel in the line. Each time an injected volume is equal to or exceeds the cell volume the current sensed value is added to the stack and the earliest value in the stack is deleted on a first in - first out basis. This earliest value is used for determining the desired stoichiometric air/fuel ratio and from this the fuel pulse width of the injectors.