US 4,438,497 A · Adaptive strategy to control internal combustion engine

Abstract

This specification discloses a method for adaptively controlling engine calibration control values. The strategy includes the steps of (1) predicting a driving pattern based on analysis of recent past driving patterns and (2) selecting engine control values appropriate for the predicted driving pattern and a desired emission constraint. The adaptive strategy adjusts spark timing and magnitude of EGR as a function of engine energy usage per distance traveled while maintaining feedgas emissions at a constant level over a wide variety of driving patterns including urban, suburban and highway. A plurality of driving cycle segments are analyzed to generate a table of engine calibration control values for the adaptive spark and EGR control strategy. This adaptive strategy has fuel consumption characteristics which are most advantageous at the most constrained feedgas levels. Drivability can be enhanced because of the greater calibration flexibility inherent to the adaptive technique.

Claims26

Dependent claims

A method for controlling the performance of a spark ignited automobile internal combustion engine using exhaust gas recirculation, the engine being responsive to the magnitude of engine control parameters, said method including the steps of:

establishing a duration of time to determine the frequency of updating the engine control parameters;
determining the energy density output of the engine over the first duration of time, wherein energy density output is the energy output divided by the distance traveled during the first duration of time;
maintaining a history of distance traveled and energy output during a plurality of successive consecutive durations of time;
estimating the magnitude of energy density output of the engine during the next duration of time;
establishing a lookup table for EGR and spark advance as functions of engine torque, engine speed, and engine energy density;
selecting a value from the table as a function of the estimated energy density for use during the next duration of time;
and
controlling the engine EGR and engine spark advance in accordance with the value selected from the table as a function of the estimated energy density thereby improving engine operation for higher efficiency.

5 more elements

A method of controlling the performance of a spark ignited automobile internal combustion engine using exhaust gas recirculating, said method including the steps of:

generating an electrical signal representative of engine revolution speed;
generating an electrical signal representative of engine manifold absolute pressure;
generating an electrical signal representative of energy density which includes energy output as a function of distance traveled of the automobile internal combustion engine;
selecting a spark angle from a set of spark angles arranged as a function of engine revolution speed, manifold absolute pressure and energy consumption;
selecting a percent of exhaust gas recirculation (EGR) from a set of EGR percents arranged as a function of engine revolution speed, manifold absolute pressure and energy consumption;
and
controlling the engine spark angle and engine percent of EGR by using the selected spark angle and percent EGR selected thereby operating the engine as a function of engine energy consumption.

4 more elements

Dependencies are inferred from the claim text.

Adaptive strategy to control internal combustion engine

Life of this patent

Adaptive strategy to control internal combustion engine

Life of this patent

Abstract

Claims26