Patent ID: 7891182

Claim:
A method for controlling an engine in a work machine, said work machine including a drive train and a hydraulic system, said drive train and said hydraulic system being powered by said engine, comprising: determining a base engine operating limit; determining a hydraulic system load on said engine; calculating a modification value for said base engine operating limit; generating a modified engine operating limit based on said modification value and said base engine operating limit; generating an engine control signal based on said modified engine operating limit; and transmitting said engine control signal to operate said engine at said modified engine operating limit to thereby supply additional power from said engine to said drive train to at least partially compensate for said hydraulic system load, said hydraulic system including a hydraulic pump powered by said engine wherein said determining said hydraulic system load step includes: determining a hydraulic pressure supplied by said hydraulic pump; and calculating said hydraulic system load based on said hydraulic pressure, said hydraulic pump having a displacement associated therewith, a pump/engine speed ratio defines a hydraulic pump speed relative to an engine speed, said calculating said hydraulic system load step calculates a hydraulic system torque load on said engine based on said hydraulic pressure, said displacement of said pump, and said pump/engine speed ratio.