US 6,286,482 B1 · Premixed charge compression ignition engine with optimal combustion control

Abstract

A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low oxides of nitrogen emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal. A processor receives the signal and generates control signals based on the engine operating condition signal for controlling various engine components to control the temperature, pressure, equivalence ratio and\or autoignition properties so as to variably control the combustion history of future combustion events to achieve stable, low emission combustion in each cylinder and combustion balancing between the cylinders.

Claims156

Dependent claims

An internal combustion engine operable in a premixed charge compression ignition mode, comprising:

an engine body;
a combustion chamber formed in the engine body for containing a mixture of fuel and air;
combustion history control means for controlling a combustion history of future combustion events to optimize engine operation, said combustion history control means including at least one of a temperature control means for varying the temperature of the mixture of fuel and air, a pressure control means for ultimately varying the pressure of the mixture, an equivalence ratio control means for varying an equivalence ratio of the mixture and a mixture autoignition property control means for varying an autoignition property of the mixture;
engine operating condition detecting means for detecting an engine operating condition indicative of the combustion history and generating an engine operating condition signal indicative of said engine operating condition;
and
processing means for receiving said engine operating condition signal, determining a combustion history value based on said engine operating condition signal, and generating one or more control signals based on said combustion history value, said one or more control signals controlling at least one of said temperature control means, said pressure control means, said equivalence ratio control means and said mixture autoignition property control means to variably control the combustion history of future combustion events.

3 more elements

A premixed charge compression ignition internal combustion engine, comprising:

an engine body;
a plurality of cylinders formed in the engine body;
a respective piston mounted in each of said plurality of cylinders for reciprocal movement, each respective piston defining a combustion chamber for containing a mixture of fuel and air;
an intake air system for supplying intake air to said plurality of cylinders;
an exhaust system for directing exhaust gas from said plurality of cylinders;
combustion history control system for controlling a combustion history of future combustion events in said combustion chamber of each of said plurality of cylinders to optimize engine operation, said combustion history control system including to optimize engine operation, said combustion history control system including at least two of a temperature control system for ultimately varying the temperature of the mixture of fuel and air, a pressure control system for ultimately varying the pressure of the mixture, and equivalence ration control system for varying an equivalence ratio of the mixture and a mixture autoignition property control system for varying an autoignition property of the mixture;
engine operating condition detecting device for detecting an engine operating condition indicative of the combustion history and generating an engine operating condition signal indicative of said engine operating condition;
and
a processor for receiving said engine operating condition signal, determining a combustion history value based on said engine operating condition signal, and generating one or more control signals based on said combustion history value, said one or more control signals controlling at least one of said temperature control system, said pressure control system, said equivalence ratio control system and said mixture autoignition property control system to variably control the combustion history of future combustion events.

6 more elements

A multi-mode internal combustion engine capable of operating in a plurality of modes for initiating combustion, comprising:

an engine body;
a combustion chamber formed in the engine body;
an intake air system for delivery intake air to said combustion chamber;
at least one of a fuel injection means mounted on said engine body for injecting fuel into one of said combustion chamber and said intake system while the engine operates in a diesel mode and a spark-ignition means mounted on said engine body for providing a spark for initiating combustion in said combustion chamber while the engine operates in a spark-ignition mode;
a premixed charge compression ignition mode control means for operating the engine in a premixed charge compression mode, said premixed charge compression ignition mode control means including combustion history control means for controlling a combustion history of future combustion events to optimize engine operation, said combustion history control means including at least one of a temperature control means for ultimately varying the temperature of the mixture of fuel and air, a pressure control means for ultimately varying the pressure of the mixture, an equivalence ratio control means for varying an equivalence ratio of the mixture and a mixture autoignition property control means for varying an autoignition property of the mixture, said premixed charge compression ignition mode control means including an engine operating condition detecting means for detecting an engine operating condition indicative of the combustion history and generating an engine operating condition signal indicative of said engine operating condition, and a premixed charge compression ignition processing means for receiving said engine operating condition signal, determining a combustion history value based on said engine operating condition signal, and generating one or more control signals based on said combustion history value, said one or more control signals controlling at least one of said temperature control means, said pressure control means, said equivalence ratio control means and said mixture autoignition property control means to variably control the combustion history of future combustion events;
and
a mode processing means for transferring engine operation between said premixed charge compression ignition mode and at least one of said diesel and said spark-ignition modes.

4 more elements

A premixed charge compression ignition internal combustion engine, comprising:

an engine body;
a plurality of cylinders formed in the engine body;
a respective piston mounted in each of said plurality of cylinders for reciprocal movement, each respective piston defining a combustion chamber for containing a mixture of fuel and air;
an intake air system for supplying intake air to said plurality of cylinders;
an exhaust system for directing exhaust gas from said plurality of cylinders;
combustion history control system for controlling a combustion history of future combustion events in said combustion chamber of each of said plurality of cylinders to optimize engine operation, said combustion history control system including at least one of a temperature control system for ultimately varying the temperature of the mixture of fuel and air, a pressure control system for ultimately varying the pressure of the mixture, an equivalence ratio control system for varying an equivalence ratio of the mixture and a mixture autoignition property control system for varying an autoignition property of the mixture;
engine operating condition detecting device for detecting an engine operating condition indicative of the combustion history and generating an engine operating condition signal indicative of said engine operating condition;
a processor for receiving said engine operating condition signal, determining a combustion history value based on said engine operating condition signal, and generating one or more control signals based on said combustion history value, said one or more control signals controlling at least one of said temperature control system, said pressure control system, said equivalence ratio control system and said mixture autoignition property control system to variably control the combustion history of future combustion events;
and
a cylinder combustion balancing means for variably adjusting operating conditions in said combustion chamber of each of said plurality of cylinders to achieve a similar combustion history for combustion events of said plurality of cylinders to balance combustion between said plurality of cylinders.

7 more elements

A method for controlling a combustion history of future combustion events in a combustion chamber of an internal combustion engine operable in a premixed charge compression ignition mode, comprising:

detecting an engine operating condition indicative of the combustion history;
generating an engine operating condition signal indicative of said engine operating condition;
processing said engine operating condition signal and determining an actual combustion history value based on said engine operating condition signal;
generating at least one control signal based on said actual combustion history value;
providing a combustion history control system for controlling a combustion history of future combustion events in the combustion chamber to optimize engine operation, said combustion history control system including at least one of a temperature control system for ultimately varying the temperature of a mixture of fuel and air for combustion in the combustion chamber, a pressure control system for ultimately varying the pressure of the mixture, an equivalence ratio control system for varying an equivalence ratio of the mixture and a mixture autoignition property control system for varying an autoignition property of the mixture;
and
providing said at least one control signal to at least one of said temperature control system, said pressure control system, said equivalence ratio control system and said mixture autoignition property control system to variably control the combustion history of future combustion events to optimize engine operation.

4 more elements

Dependencies are inferred from the claim text.

Premixed charge compression ignition engine with optimal combustion control

Life of this patent

Premixed charge compression ignition engine with optimal combustion control

Life of this patent

Abstract

Claims156