Methods and systems for variable geometry turbocharger control

A system for positioning a variable geometry member in a turbocharger that is coupled to an internal combustible engine, said system comprising:

• a boost target map for determining a boost pressure target for said turbocharger;
• an engine control unit configured to calculate an error value, errboost, between the boost pressure target and an actual measured boost pressure to determine a second new variable geometry member position for the turbocharger based on a measured speed of the engine;
• a proportional integral differential module configured to determine a first new variable geometry member position for said turbocharger based on said errboost;
• an open-loop control module configured to determine a second new variable geometry member position based on engine speed;
• and
• an actuator configured to position said variable geometry member according to said first new variable geometry member position when the engine is in a power mode, and according to the second new variable geometry member position when the engine is in a braking mode.

A method for positioning a variable geometry member in a turbocharger that is coupled to an internal combustible engine, said method comprising steps of:

• determining a boost pressure target for said turbocharger;
• calculating a first error value, errboost, between said boost pressure target and a measured actual boost pressure;
• generating a turbo speed target for said turbocharger based on said errboost;
• calculating a second error value, errspeed, between said turbo speed target and a measured actual turbo speed of said turbocharger;
• determining a new variable geometry member position for said turbocharger based on said errspeed;
• and
• positioning said variable geometry member according to said new variable geometry member position.

A system for positioning a variable geometry member disposed within a turbocharger that is coupled to an internal combustible engine, said system comprising:

• a boost target map for determining a boost pressure target for said turbocharger;
• an engine control unit configured to calculate a first error value, errboost, between said boost pressure target and a measured actual boost pressure;
• a first proportional integral differential module configured to generate a turbo speed target for said turbocharger based on said errboost, said engine control unit being further configured to calculate a second error value, errspeed, between said turbo speed target and an actual turbo speed of said turbocharger;
• a second proportional integral differential module configured to generate a new variable geometry member position for said turbocharger based on said errspeed;
• and
• an actuator configured to position said variable geometry member according to said new variable geometry member position.

A method for positioning a variable geometry member disposed within a turbocharger that is coupled to an internal combustible engine, said method comprising steps of:

• determining a boost pressure target for said turbocharger;
• calculating a first error value, errboost, between said boost pressure target and a measured actual boost pressure;
• generating a first turbo speed target for said turbocharger based on said errboost;
• determining a turbine pressure target for said turbocharger;
• calculating a second error value, errturbine, between said turbine pressure target and a measured actual turbine pressure;
• generating a second turbo speed target for said turbocharger based on said errturbine;
• selecting said first turbo speed target when said engine is in a power mode, and selecting said second turbo speed target when said engine is in a braking mode to produce a selected turbo target speed;
• calculating a third error value, errspeed, between said selected turbo speed target and a measured actual turbo speed;
• determining a new variable geometry member position for said turbocharger based on said errspeed;
• and
• positioning said variable geometry member according to said new variable geometry member position.

A system for positioning a variable geometry member disposed within a turbocharger that is coupled to an internal combustible engine, said system comprising:

• a boost target map for determining a boost pressure target for said turbocharger;
• an engine control unit configured to calculate a first error value, errboost, between said boost pressure target and a measured actual boost pressure;
• a first proportional integral differential module configured to generate a first turbo speed target for said turbocharger based on said errboost;
• a turbine pressure map for determining a turbine pressure target for said turbocharger, said engine control unit being further configured to calculate a second error value, errturbine, between said turbine pressure target and a measured actual turbine pressure;
• a second proportional integral differential module configured to generate a second turbo speed target for said turbocharger based on said errturbine, said engine control unit being further configured to select said first turbo speed target when said engine is in a power mode, and to select said second turbo speed target when said engine is in a braking mode to produce a selected turbo target speed, and to calculate a third error value, errspeed, between said selected turbo speed target and an actual turbo speed;
• a third proportional integral differential module configured to determine a new variable geometry member position for said turbocharger based on said errspeed;
• and
• an actuator configured to position the variable geometry member of said turbocharger according to said new variable geometry member position.