Fail-soft turbocharger control system

• US 4,604,701 A
• Filed: 02/16/1983
• Issued: 08/05/1986
• Est. Priority Date: 02/16/1983
• Status: Expired due to Fees

• Current Assignee: Allied Corporation Columbia Road and Park Avenue Morris Township New Jersey
• Original Assignee: Allied Corp. (Honeywell International Inc.)
• Inventors: Fujawa, Charles S., Masteller, Sara B.
• Primary Examiner(s): Gruber, Felix D.
• Application Number:
  US06/467,070
• Time in Patent Office: 1,266 Days
• Field of Search: 60/600, 60/601, 60/602, 60/603, 364/431.01, 364/431.11, 364/550, 364/551
• US Class Current: 701/99
• CPC Class Codes: F02B 37/24 by using pumps or turbines with adjustable guide vanes
• CPC Class Codes: F02D 2041/1409 using at least a proportional, integral or derivative controller
• CPC Class Codes: F02D 41/0007 for control of turbo-charged or super-charged engines control of the pumps per se F02B37/12
• CPC Class Codes: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In a turbocharger control system which includes fault testing circuitry which automatically senses and compares engine operating parameters of manifold pressure, exhaust temperature, engine speed, and actuator position, compares the sensed values to predetermined norms to establish the validity of the signals, in which substitutes preestablished values for the sensed signals when the sensed signal is determined to be invalid. The substituted value may be a value stored in the memory of a microprocessor used in the system or a value derived from a signal received from a different but corresponding sensor of the engine being controlled.

Claims

1. A fail-soft turbocharger control system for an engine having at least one bank of cylinders and at least one turbocharger associated therewith, said turbocharger having a variable output compressor boosting the pressure of an input manifold to said bank of cylinders and a variable input turbine driving said compressor and powered by the exhaust gases of said bank of cylinders, said control system comprising:

a computing circuit including input circuit means for receiving input signals representative of operational perameters of said engine, programmable memory means for storing predetermined tabular data and sequential and computational instructions, means responsive to said memory means for receiving sensor input signals and generating a plurality of output signals as a function of said input signals, tabular data, and instructions, and output circuit means for outputting said plurality of output signals,

sensor means connected to said engine and said computing circuit for sensing the manifold pressure, exhaust gas temperature, engine speed, and position of the throttle, compressor and turbine actuators of said engine and generating said sensor input signals;

and actuator means connected to said output circuit means for controlling the position of said actuators in response to predetermined ones of said output signals, respectively,

said computing circuit, sensor means, and actuator means defining a turbine control loop for regulating the input of exhaust gases to the turbine as a function of the error difference between the optimum manifold pressure of said bank of cylinders and the actual manifold pressure of said bank of cylinders;

wherein said optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine and said stored tabular data,

a compressor control loop for regulating the output of the airflow from the compressor as a function of said stored tabular data and at least one operating parameter of the engine including the speed of the engine;

and fault testing means for testing the validity of said sensor input signals, said fault testing means including means for generating an RPM signal indicative of the actual speed of the engine; and

means for determining whether the value of said speed signal is valid before regulating the turbine input and compressor output with that value.

2. A control system as defined in claim 1, wherein said speed signal validity determination means further includes:

means for setting said signal value to a constant when it is determined that the actual speed signal value is invalid.

3. A control system as defined in claim 1, wherein said optimum manifold pressure is additionally calculated as a function of the exhaust gas temperature of said bank of cylinders, further comprising:

means for generating a temperature signal indicative of the actual exhaust gas temperature of said bank of cylinders; and

means for determining whether the value of said temperature signal is valid prior to regulating the turbine input with that value.

4. A control system as defined in claim 3, wherein said temperature signal validity determination means further includes:

means for setting said temperature signal value to a constant when it is determined that the actual temperature signal value is invalid.

5. A control system as defined in claim 1, including:

means for determining whether the value of said manifold pressure signal is valid prior to regulating the turbine input with that value.

6. A control system as defined in claim 5, including:

means for setting the turbine input to a fail-safe position when it is determined that the actual manifold pressure signal value is invalid.

7. A fail-soft turbocharger control system for an engine having at least one bank of cylinders and at least one turbocharger associated therewith, said turbocharger having a variable output compressor boosting the pressure of an input manifold to said bank of cylinders and a variable input turbine powered by the exhaust gas of said bank of cylinders for driving said compressor, said control system comprising:

a computing circuit including input circuit means for receiving sensor input signals representative of operational parameters of said engine, programmable memory means for storing predetermined tabular data and sequential and computational instructions, means responsive to said memory means for receiving said input signals and generating a plurality of output signals as a function of said input signals, tabular data, and instructions, and output circuit means for outputting said plurality of output signals,

sensor means connected to said engine and a said computing circuit for sensing and generating sensor input signals representative of the manifold pressure, exhaust gas temperature, engine speed, and position of the throttle, compressor and turbine actuators of said engine,

and actuator means connected to said output circuit means for controlling the position of said actuators in response to predetermined ones of said output signals, respectively, said computing circuit, sensor means, and actuator means defining a turbine control loop for regulating the input of exhaust gases to the turbine as a function of the error difference between the optimum manifold pressure of said bank of cylinders and the actual manifold pressure of said bank of cylinders;

wherein the optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine and the temperature of the exhaust gas;

a compressor control loop for regulating the output of the airflow from the compressor as a function of at least one operating parameter of the engine including the speed of the engine;

means for generating an RPM signal indicative of the actual speed of the engine;

means for generating a temperature signal indicative of the actual exhaust gas temperature of said bank of cylinders;

and fault testing means for testing the validity of said sensor input signals, said fault testing means including a first means for determining whether the value of the RPM signal is valid prior to regulating either the turbine inlet or compressor output with that value, said first determining means including means for comparing the RPM signal value with a reference level if the temperature signal value is within an operational range of values for the engine.

8. A control system as defined in claim 7, wherein said fault testing means further includes:

second means for determining whether the value of the temperature signal is valid prior to regulating the turbine inlet with that value, said second determining means including means for comparing the temperature signal with a reference level if the RPM signal value is within an operational range of values for the engine.

9. A control system as defined in claim 7, wherein said fault testing means further comprises:

means for generating a manifold pressure signal indicative of the actual manifold pressure of said bank of cylinders; and

third means for determining whether the value of said manifold pressure signal is valid prior to regulating the turbine input with that value, said third determining means including means for comparing the manifold pressure signal with a reference level if the temperature signal value is within an operational range of values for the engine.

10. A fail-soft turbocharger control system for an engine with a first bank and second bank of cylinders and a first turbocharger and second turbocharger associated therewith, each turbocharger having a variable output compressor boosting the pressure of an input manifold to said associated bank of cylinders and a variable input turbine driving said compressor powered by the exhaust gases of said bank of cylinders for said control system comprising:

a computing circuit including input circuit means for receiving sensor input signals representative of operational parameters of said engine, programmable memory means for storing predetermined tabular data and sequential and computational instructions, means responsive to said memory means for receiving said input signals and generating a plurality of said output signals as a function of said input signals, tabular data, and instructions, and output circuit means for outputting said plurality of output signals,

sensor means connected to said engine and said computing circuit for sensing and generating said sensor input signals representative of the manifold pressure, exhaust gas temperature, engine speed, and the position of the throttle, compressor and turbine actuators of said engine,

and actuator means connected to said output circuit means for controlling the position of said actuators in response to predetermined ones of said output signals, respectively,

said computing circuit, sensor means, and actuator means defining a first turbine control loop for regulating the input of exhaust gases to the first turbine as a function of the error difference between the optimum manifold pressure of said first bank of cylinders and the actual manifold pressure of said first bank of cylinders;

wherein said optimum manifold pressure is calculated from said stored tabular data and at least one operating parameter of the engine including the speed of the engine;

a first compressor control loop for regulating the output of the airflow from the first compressor as a function of at least one operating parameter of the engine including the speed of the engine;

a second turbine control loop for regulating the input of exhaust gases to the second turbine as a function of the error difference between the optimum manifold pressure of said second bank of cylinders and the actual manifold pressure of said second bank of cylinders;

wherein said optimum manifold pressure is calculated from said stored tabular data and at least one operating parameter of the engine including the speed of the engine;

a second compressor loop for regulating the output of the airflow from the second compressor as a function of said stored tabular data and at least one operating parameter of the engine including the speed of the engine;

fault testing means for testing the validity of said sensor input signals, said fault testing means including means for determining whether the value of said speed signal is valid before regulating either the first and second turbine inputs or the first and second compressor outputs with that value.

11. A control system as defined in claim 10, wherein said speed signal validity determining means further includes:

means for setting said speed signal value to a constant when it is determined that the actual speed signal is invalid.

12. A control system as defined in claim 10, wherein said fault testing means further comprises:

a first means for generating a first manifold pressure signal indicative of the actual manifold pressure of said first bank of cylinders;

a second means for generating a second manifold pressure signal indicative of the actual manifold pressure of said second bank of cylinders; and

means for determining whether the values of said first and second manifold pressure signals are valid prior to regulating the first and second turbine inlets with those signals.

13. A control system as defined in claim 10, wherein said fault testing means further comprises:

a first means for generating a first temperature signal indicative of the actual temperature of the exhaust gas of the first bank;

a second means for generating a second temperature signal indicative of the actual temperature of the exhaust gas of the second bank;

means for determining whether the values of said first and second temperature signals are valid prior to regulating the first and second compressor outputs with those signals.

14. A fail-soft turbocharger control system for an engine with a first bank and second bank of cylinders and a first turbocharger and second turbocharger associated therewith, each turbocharger having a variable output compressor boosting the pressure of an input manifold to said bank cylinders and variable input turbine driving said compressor powered by the exhaust gases of said bank of cylinders for said control system comprising:

a computing circuit including input circuit means for receiving sensor input signals representative of operational parameters of said engine, programmable memory means for storing predetermined tabular data and sequential and computational instructions, means responsive to said memory means for receiving said input signals and generating a plurality of output signals as a function of said input signals, tabular data, and instructions, and output circuit means for ouputting said plurality of output signals,

sensor means connected to said engine and said computing circuit for sensing and generating said sensor input signals representative of the manifold pressure, exhaust gas temperature, engine speed, and positions of the throttle, compressor, and turbine actuators of said engine,

and actuator means connected to said output circuit means for controlling the position of said actuators in response to predetermined ones of said output signals, respectively, said computing circuit, sensor means, and actuator means defining a first turbine control loop for regulating the input of exhaust gases to the first turbine as a function of the error difference between the optimum manifold pressure of said first bank of cylinders and the actual manifold pressure of said first bank of cylinders;

wherein said optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine;

a first compressor control loop for regulating the output of the airflow from the first compressor as a function of at least one operating parameter of the engine including the speed of the engine;

a second turbine control loop for regulating the input of exhaust gases to the second turbine as a function of the error difference between the optimum manifold pressure of said second bank of cylinders and the actual manifold pressure of said second bank of cylinders;

wherein said optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine;

a second compressor control loop for regulating the output of the airflow from the second compressor as a function of at least one operating parameter of the engine including the speed of the engine;

and fault testing means comprising for generating a first temperature signal indicative of the actual temperature of the exhaust gas of the first bank;

a second means for generating a second temperature signal indicative of the actual temperature of the exhaust gas of the second bank;

means for determining whether the value of said RPM signal is valid before regulating either the first and second turbine inputs or the first and second compressor outputs with that value;

said determining means including means for comparing the RPM signal with a reference level if either the first or second temperature signal is within the operational range of values for the engine.

15. A fail-soft turbocharger control system for an engine with a first bank and second bank of cylinders and a first turbocharger and second turbocharger associated therewith, each turbocharger having a variable output compressor boosting the pressure of an input manifold to said bank of cylinders and a variable input turbine driving said compressor powered by the exhaust gases of said bank of cylinders for said control system comprising:

a computing circuit including input circuit means for receiving sensor input signals representative of operational parameters of said engine, programmable memory means for storing predetermined tabular data and sequential and computational instructions, means responsive to said memory means for receiving said input signals and generating a plurality of output signals as a function of said input signals, tabular data, and instuctions, and output circuit means for outputting said plurality of output signals,

sensor means connected to said engine and a said computing circuit for sensing and generating said sensor input signals representative of the manifold pressure, exhaust gas temperature, engine speed, and position of the throttle, compressor and turbine actuators of said engine,

and actuator means connected to said output circuit means for controlling the position of said actuators in response to predetermined ones of said output signals, respectively, said computing circuit, sensor means, and actuator means defining;

a first turbine control loop for regulating the input of exhaust gases to the first turbine as a function of the error difference between the optimum manifold pressure of said first bank of cylinders and the actual manifold pressure of said bank of cylinders;

wherein said optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine;

a first compressor control loop for regulating the output of the airflow from the first compressor as a function of at least one operating parameter of the engine including the speed of the engine;

a second turbine control loop for regulating the input of exhaust gases to the second turbine as a function of the error difference between the optimum manifold pressure of said second bank of cylinders and the actual manifold pressure of said second bank of cylinders;

wherein said optimum manifold pressure is calculated from at least one operating parameter of the engine including the speed of the engine;

a second compressor control loop for regulating the output of the airflow from the second compressor as a function of at least one operating parameter of the engine including the speed of the engine;

fault testing means for testing the validity of said sensor signals, said fault testing means including;

means for generating an RPM signal indicative of the actual speed of the engine; and

;

a first means for generating a first temperature signal indicative of the actual temperature of the exhaust gas of the first bank;

a second means for generating a second temperature signal indicative of the actual temperature of the exhuast gas of the second bank; and

means for determining whether the value of said first temperature signal is valid prior to regulating the first turbine input with that value, said determining means including means for comparing said first temperature signal with a reference level if said RPM signal is within an operational range of values for the engine.

16. A control system as defined in claim 15, in which said fault testing means further includes:

means for determining whether the value of said second temperature signal is valid prior to regulating the second turbine input with that value, said determining means including means for comparing said second temperature signal with a reference level if said RPM signal is within an operational range of values for the engine.

17. A control system as defined in claim 16, wherein said fault testing means further includes:

means for replacing the value of one of said temperature signals with the value of the other of said temperature signals if the one temperature signal value is determined to be invalid and the other temperature signal value is determined to be valid, or for replacing the value of temperature signals with a constant value if both temperature signal values are determined to be invalid.