Abstract: A method of operating a gaseous fuel internal combustion engine comprises performing at least one measurement relating to the combustion of a mixture of gaseous fuel and air in a combustion chamber of an associated cylinder in a combustion cycle. At least one combustion parameter, for example, a start of combustion, is determined based on the at least one measurement. When the combustion parameter differs from a desired combustion parameter, an ignition device associated with the cylinder is controlled based on the comparison in order to control the combustion in the current combustion cycle.

Abstract: An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (VI) is applied to the balancing algorithm. The offset input value (VI) may cause the balancing algorithm to adjust the control output (O1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (VO) to more rapidly vary the fuel supply or ignition timing, with the offset input value (VI) being selected for example to compensate for the resulting change in the control input (I1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

Abstract: A controller for an internal combustion engine is configured to operate the engine at a desired output power and at a desired air/fuel ratio provided in the cylinder, the desired air/fuel ratio depending on an amount of air, the primary fuel, and the secondary fuel provided to the cylinder selectively; gradually increase a power output of the engine during a transient event from an initial power output, to an intermediate power output, and then to a final power output; during the transient event, simultaneously with the power output increase, increase the amount of the primary fuel and the secondary fuel to produce a rich air/fuel ratio in the cylinder.

Abstract: A controller for an internal combustion engine is configured to operate the engine at a desired output power and at a desired air/fuel ratio provided in the cylinder, the desired air/fuel ratio depending on an amount of air, the primary fuel, and the secondary fuel provided to the cylinder selectively; gradually increase a power output of the engine during a transient event from an initial power output, to an intermediate power output, and then to a final power output; during the transient event, simultaneously with the power output increase, increase the amount of the primary fuel and the secondary fuel to produce a rich air/fuel ratio in the cylinder.

Abstract: A method for starting a gaseous fuel internal combustion engine is disclosed. According to the disclosed method, the engine is rotated using a start device until a first speed threshold is reached. After reaching the first speed threshold, pilot fuel is supplied to a plurality of cylinders of the engine to combust the same. After performing an ignition health check, gaseous fuel is supplied to all or a relatively large number of cylinders to start accelerating the engine up to a second speed threshold.

Abstract: An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (VI) is applied to the balancing algorithm. The offset input value (VI) may cause the balancing algorithm to adjust the control output (O1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (VO) to more rapidly vary the fuel supply or ignition timing, with the offset input value (VI) being selected for example to compensate for the resulting change in the control input (I1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

Abstract: A method of operating a gaseous fuel internal combustion engine comprises performing at least one measurement relating to the combustion of a mixture of gaseous fuel and air in a combustion chamber of an associated cylinder in a combustion cycle. At least one combustion parameter, for example, a start of combustion, is determined based on the at least one measurement. When the combustion parameter differs from a desired combustion parameter, an ignition device associated with the cylinder is controlled based on the comparison in order to control the combustion in the current combustion cycle.

Abstract: A method for starting a gaseous fuel internal combustion engine is disclosed. According to the disclosed method, the engine is rotated using a start device until a first speed threshold is reached. After reaching the first speed threshold, pilot fuel is supplied to a plurality of cylinders of the engine to combust the same. After performing an ignition health check, gaseous fuel is supplied to all or a relatively large number of cylinders to start accelerating the engine up to a second speed threshold.

Abstract: A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The method includes operating the internal combustion engine on gaseous fuel by repeatedly actuating the gaseous fuel admission valve. The method further includes measuring a sequence of temporal developments of an electrical operation parameter respectively associated with an actuation of the gaseous fuel admission valve. The sequence includes a first temporal development to be evaluated and a plurality of temporal developments preceding the first temporal development. The method also includes evaluating operability of the gaseous fuel admission valve based on the first temporal development of the measured sequence and at least one of the plurality of preceding temporal developments of the measured sequence.

Abstract: A method for controlling an internal combustion engine is disclosed. The method may include receiving knock data corresponding to knock levels over a time period. The method may also include determining from the knock data whether the knock levels change over the time period. Further, the method may include determining that a variation in the gas composition of the gaseous fuel supplied to the internal combustion engine has occurred when the knock levels change over the time period. In addition, the method may include adjusting an operating condition of the internal combustion engine to adapt a knock susceptibility of the internal combustion engine to the varying gas composition.

Abstract: A method for supplying fuel to an engine is disclosed. The method may include regulating a gas admission valve disposed between a gaseous fuel line and a cylinder intake port to reduce flow of gaseous fuel to the cylinder. The method may also include closing a shut-off valve disposed between a gaseous fuel reservoir and the gaseous fuel line to restrict flow of gaseous fuel from the gaseous fuel reservoir to the gaseous fuel line. Further, the method may include actuating an inert gas inlet valve disposed between an inert gas reservoir and the gaseous fuel line to supply inert gas to the gaseous fuel line and flush the gaseous fuel in the gaseous fuel line into the cylinder via the gas admission valve. Additionally, the method may include closing the inert gas inlet valve to restrict supply of inert gas to the gaseous fuel line.

Abstract: A method of operating a gas or dual fuel engine having a plurality of cylinders, includes monitoring a characteristic of each of the plurality of cylinders during operation of the gas or dual fuel engine. The method also includes detecting a pre-ignition condition associated with one or more cylinders of the plurality of cylinders based on the monitored characteristic. The method further includes reducing fuel supply to the one or more cylinders having the pre-ignition condition. The fuel supply to remaining cylinders of the plurality of cylinders is increased, to maintain a constant power output of the gas or dual fuel engine. The method further includes adjusting an amount of air supplied to each of the plurality of cylinders based on the increased amount of fuel supplied to the remaining cylinders, to maintain an air-to-fuel ratio within a desired range.

Abstract: A method for controlling an internal combustion engine is disclosed. The method may include receiving knock data corresponding to knock levels over a time period. The method may also include determining from the knock data whether the knock levels change over the time period. Further, the method may include determining that a variation in the gas composition of the gaseous fuel supplied to the internal combustion engine has occurred when the knock levels change over the time period. In addition, the method may include adjusting an operating condition of the internal combustion engine to adapt a knock susceptibility of the internal combustion engine to the varying gas composition.

Abstract: A method for supplying fuel to an engine is disclosed. The method may include regulating a gas admission valve disposed between a gaseous fuel line and a cylinder intake port to reduce flow of gaseous fuel to the cylinder. The method may also include closing a shut-off valve disposed between a gaseous fuel reservoir and the gaseous fuel line to restrict flow of gaseous fuel from the gaseous fuel reservoir to the gaseous fuel line. Further, the method may include actuating an inert gas inlet valve disposed between an inert gas reservoir and the gaseous fuel line to supply inert gas to the gaseous fuel line and flush the gaseous fuel in the gaseous fuel line into the cylinder via the gas admission valve. Additionally, the method may include closing the inert gas inlet valve to restrict supply of inert gas to the gaseous fuel line.

Abstract: A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The method includes operating the internal combustion engine on gaseous fuel by repeatedly actuating the gaseous fuel admission valve. The method further includes measuring a sequence of temporal developments of an electrical operation parameter respectively associated with an actuation of the gaseous fuel admission valve. The sequence includes a first temporal development to be evaluated and a plurality of temporal developments preceding the first temporal development. The method also includes evaluating operability of the gaseous fuel admission valve based on the first temporal development of the measured sequence and at least one of the plurality of preceding temporal developments of the measured sequence.

Abstract: A method of operating a gas or dual fuel engine having a plurality of cylinders, includes monitoring a characteristic of each of the plurality of cylinders during operation of the gas or dual fuel engine. The method also includes detecting a pre-ignition condition associated with one or more cylinders of the plurality of cylinders based on the monitored characteristic. The method further includes reducing fuel supply to the one or more cylinders having the pre-ignition condition. The fuel supply to remaining cylinders of the plurality of cylinders is increased, to maintain a constant power output of the gas or dual fuel engine. The method further includes adjusting an amount of air supplied to each of the plurality of cylinders based on the increased amount of fuel supplied to the remaining cylinders, to maintain an air-to-fuel ratio within a desired range.

Abstract: A method of evaluating operability of a gaseous fuel admission valve of an internal combustion engine is disclosed. The internal combustion engine includes a plurality of cylinders and at least one gaseous fuel admission valve for each cylinder of the plurality of cylinders. The method includes operating the dual fuel internal combustion engine on liquid fuel. The method further includes supplying gaseous fuel to the gaseous fuel admission valves at a pressure above an intake manifold air pressure thereby setting a differential gas pressure across the gaseous fuel admission valves. The method also includes operating the gaseous fuel admission valves to add gaseous fuel to intake air while operating the dual fuel internal combustion engine primarily on liquid fuel. Further, the method includes measuring combustion process parameters for the cylinders. The method also includes evaluating operability of the gaseous fuel admission valves based on the measured combustion process parameters.