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A method for controlling intake airflow in an internal combustion engine including an intake air compressor includes determining a first compressor boost signal based upon a predetermined intake manifold pressure command, determining a second compressor boost signal based upon a predetermined exhaus

A method for controlling intake airflow in an internal combustion engine including an intake air compressor includes determining a first compressor boost signal based upon a predetermined intake manifold pressure command, determining a second compressor boost signal based upon a predetermined exhaust pressure limit, determining a compressor boost control command based upon the first compressor boost signal and a limit comprising one of a maximum boost setting and said second compressor boost signal, and controlling the intake air compressor in response to the compressor boost control command.

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1. Method for controlling intake airflow in an internal combustion engine including an intake air compressor, comprising, within a control module; determining a first compressor boost signal based upon a predetermined intake manifold pressure command;determining a second compressor boost signal base

1. Method for controlling intake airflow in an internal combustion engine including an intake air compressor, comprising, within a control module; determining a first compressor boost signal based upon a predetermined intake manifold pressure command;determining a second compressor boost signal based upon a predetermined exhaust pressure limit;determining a compressor boost control command based upon the first compressor boost signal and a compressor boost limit comprising one of a maximum boost setting and said second compressor boost signal;controlling the intake air compressor to operate at a position that controls flow of intake air to the internal combustion engine in response to the compressor boost control command; andoperating the internal combustion engine with the intake air compressor operating at the compressor boost control command, comprising maintaining exhaust pressure of the internal combustion engine at the predetermined exhaust pressure limit. 2. The method of claim 1, wherein said intake air compressor is included in a variable-geometry turbocharger (VGT) and determining said second compressor boost signal comprises employing an inverse VGT model in feed-forward operation configured in accordance with the following relationship: VGT=F-1⁡(Pr,m.ex⁢RTexPex)wherein VGT is a modeled VGT position signal, Pex is exhaust gas pressure,Tex is exhaust gas temperature,R is ideal gas constant, Pr=PstPex is the pressure ratio across a turbine of the variable-geometry turbocharger,Pst is a turbine outlet pressure, and{dot over (m)}ex is exhaust mass flowrate. 3. The method of claim 2, wherein the exhaust mass flowrate {dot over (m)}ex includes compensation for dynamic transport delay. 4. The method of claim 3, wherein the compensation for dynamic transport delay is determined in accordance with the following relationship: m.ex=1-τ2⁢s1+τ2⁢s⁢m.f+1-(τ1+τ2)⁢s1+(τ1+τ2)⁢s⁢m.awherein τ1 is air flow transportation delay, τ2 is combustion process delay,τ1+τ2 is mass airflow delay to turbine inlet,{dot over (m)}f is mass fuel flow,{dot over (m)}a is mass air flow. 5. The method of claim 2, wherein determining said second compressor boost signal comprises a feedback loop including a signal correction to said modeled VGT position signal based on PID processing of the deviation of engine exhaust pressure from said predetermined exhaust pressure limit. 6. The method of claim 5, wherein PID processing is suspended when engine exhaust pressure does not exceed said predetermined exhaust pressure limit. 7. The method of claim 1, wherein said intake air compressor comprises a variable-geometry turbocharger (VGT) and determining said second compressor boost signal comprises employing an inverse VGT model in feed-forward operation configured in accordance with the following relationship: VGT=Ω-1⁡(Pr,m.ex⁢RTexPex⁢f1⁡(Pr))wherein VGT is a modeled VGT position signal, Pex is exhaust gas pressure,Tex is exhaust gas temperature,R is ideal gas constant, Pr=PstPex is the pressure ratio across a turbine of the variable-geometry turbocharger,Pst is a turbine outlet pressure,{dot over (m)}ex is exhaust mass flowrate, and f1={2⁢γγ-1⁢(Pr2m-Prm+1m)PRc