Abstract: A method for estimating a quality of reductant in an engine aftertreatment system for an engine using a virtual sensor, the method comprising: determining whether an enablement condition is met, wherein the enablement condition is one or more of: a reductant fill condition determined based on data received from one or more float sensors associated with the engine; a machine start condition determined based on machine speed data obtained from a speed sensor associated with the engine; and/or a rationality check condition determined based on data associated with a fault of one or more sensors associated with the engine; upon determining that the enablement condition is met, receiving NOx measurement data obtained from at least one NOx sensor; generating a reductant quality value based on the NOx measurement data; and outputting a reductant quality determination based on the reductant quality value.

Abstract: A method for estimating a quality of reductant in an engine aftertreatment system for an engine using a virtual sensor, the method comprising: determining whether an enablement condition is met, wherein the enablement condition is one or more of: a reductant fill condition determined based on data received from one or more float sensors associated with the engine; a machine start condition determined based on machine speed data obtained from a speed sensor associated with the engine; and/or a rationality check condition determined based on data associated with a fault of one or more sensors associated with the engine; upon determining that the enablement condition is met, receiving NOx measurement data obtained from at least one NOx sensor; generating a reductant quality value based on the NOx measurement data; and outputting a reductant quality determination based on the reductant quality value.

Abstract: A damage analysis and control system is disclosed. An example process may include receiving a data set of measurements associated with a period of operation of a power system. The data set of measurements may identify a frequency that the power system is in an operating state during the period of operation, and the data set of measurements may identify a frequency of damage measurements associated with the operating state. The process may include determining, using a damage model and the data set of measurements, a damage score for the operating state during the period of operation of the power system. The process may include determining that the damage score satisfies a threshold damage score associated with the damage model and performing an action associated with the power system based on the damage score satisfying the threshold damage score.

Abstract: A damage analysis and control system is disclosed. An example process may include receiving a data set of measurements associated with a period of operation of a power system. The data set of measurements may identify a frequency that the power system is in an operating state during the period of operation, and the data set of measurements may identify a frequency of damage measurements associated with the operating state. The process may include determining, using a damage model and the data set of measurements, a damage score for the operating state during the period of operation of the power system. The process may include determining that the damage score satisfies a threshold damage score associated with the damage model and performing an action associated with the power system based on the damage score satisfying the threshold damage score.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid load loss transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled relative to the gas rail pressure in order to maintain the liquid rail pressure greater than the gas pressure during the transient to avoid migration gaseous fuel into the liquid fuel side of the system.

Abstract: A common rail fuel system includes a common rail supplied by an inlet metered high pressure pump and fluidly connected to a plurality of zero-leak fuel injectors. An electronic controller controls pressure in the common rail predominantly responsive to a rail pressure error when outside of an overshoot avoidance condition corresponding to the error being less than a first threshold and a time rate of change of the error being greater than a second threshold. Pressure in the common rail is controlled predominantly responsive to the time rate of change of the error during the overshoot avoidance condition.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid fueling increase transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled toward an elevated liquid pressure in order to cause a surge in the supply of gaseous fuel to the gaseous fuel common rail to proactively satisfy the increased gaseous fuel injection rate while obviating a substantial pressure deficit in the gaseous fuel common rail.

Abstract: A system, related method and computer program product are disclosed for controlling fuel mass of CNG received by an engine. The system may comprise a heat exchanger configured to receive CLNG and supply coolant and to output CNG and return coolant, an injector configured to inject CNG into the engine, a gas line between the injector and heat exchanger, a control valve configured to receive return coolant from the heat exchanger and to change the amount of return coolant flowing through control valve, and a controller connected to the control valve. The gas line may be configured to carry CNG from the heat exchanger to the injector. The controller may be configured to maintain a Gas Line Temperature within an operating range by adjusting the amount of return coolant flowing through the control valve based, at least in part, on the Gas Line Temperature and a Target Return Coolant Temperature.

Abstract: A method of detecting leakage of a fluid from a tank is disclosed. The method may include determining cumulative commanded fluid consumption of the fluid in the tank over a selected time period, determining an actual change of a volume of the fluid in the tank over the selected time period, and comparing the cumulative commanded fluid consumption to the actual change of volume of the fluid. The method may further include producing a leak warning upon the actual change of volume of the fluid over the selected time period exceeding the cumulative commanded fluid consumption over the selected time period plus a threshold value.

Abstract: A common rail fuel system diagnostic algorithm is executed by an engine control and real time to detect and identify a faulty fuel system component. Rail pressure data is processed through a digital resonating filter having a resonance frequency corresponding to a fault signature. A peak magnitude and phase of the output from the digital resonating filter reveals a degradation level of a fuel injector, and a phase of the output identifies which fuel injector is faulted.

Abstract: A method for fault diagnosis in a fuel injection system having first and second fuel injectors. The method includes initiating a current flow in the first and second fuel injectors. Further, a rise duration of the current flow to reach a threshold level is measured. The method further includes comparing the rise duration and a preset duration. The fuel injection system is controlled based on the comparison.

Abstract: A dual fuel common rail system may be operated in a regular mode in which a relatively large charge of gaseous fuel is ignited by compression igniting a relatively small injection quantity of liquid diesel fuel. The dual fuel system may be operated in a single fuel limp home mode in which liquid diesel fuel is injected at higher pressures. When transitioning from the single fuel limp home mode to the dual fuel regular mode, accumulated leaked liquid fuel in the gaseous nozzle chamber of each fuel injector is purged and burned in the respective engine cylinder.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Prior to servicing the engine, a service tool may establish a communication link with an electronic controller that controls operation of the engine. Pressure information for a gaseous fuel common rail and a liquid fuel common rail are displayed with the service tool, when the engine is stopped, in order to determine whether the rails are completely depressurized indicating that it is then o.k. to perform servicing tasks.

Abstract: A method of detecting leakage of a fluid from a tank is disclosed. The method may include determining cumulative commanded fluid consumption of the fluid in the tank over a selected time period, determining an actual change of a volume of the fluid in the tank over the selected time period, and comparing the cumulative commanded fluid consumption to the actual change of volume of the fluid. The method may further include producing a leak warning upon the actual change of volume of the fluid over the selected time period exceeding the cumulative commanded fluid consumption over the selected time period plus a threshold value.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid fueling increase transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled toward an elevated liquid pressure in order to cause a surge in the supply of gaseous fuel to the gaseous fuel common rail to proactively satisfy the increased gaseous fuel injection rate while obviating a substantial pressure deficit in the gaseous fuel common rail.

Abstract: A compression ignition engine is fueled from common rail fuel injectors that predominately inject natural gas fuel that is compression ignited with a small pilot injection of liquid diesel fuel. Before and after a rapid load loss transient, the liquid and gaseous rail pressures are controlled toward respective pressures based upon engine speed and load. During the transient, the liquid rail pressure is controlled relative to the gas rail pressure in order to maintain the liquid rail pressure greater than the gas pressure during the transient to avoid migration gaseous fuel into the liquid fuel side of the system.

Abstract: A system, related method and computer program product are disclosed for controlling fuel mass of CNG received by an engine. The system may comprise a heat exchanger configured to receive CLNG and supply coolant and to output CNG and return coolant, an injector configured to inject CNG into the engine, a gas line between the injector and heat exchanger, a control valve configured to receive return coolant from the heat exchanger and to change the amount of return coolant flowing through control valve, and a controller connected to the control valve. The gas line may be configured to carry CNG from the heat exchanger to the injector. The controller may be configured to maintain a Gas Line Temperature within an operating range by adjusting the amount of return coolant flowing through the control valve based, at least in part, on the Gas Line Temperature and a Target Return Coolant Temperature.

Abstract: A dual fuel common rail system may be operated in a regular mode in which a relatively large charge of gaseous fuel is ignited by compression igniting a relatively small injection quantity of liquid diesel fuel. The dual fuel system may be operated in a single fuel limp home mode in which liquid diesel fuel is injected at higher pressures. When transitioning from the single fuel limp home mode to the dual fuel regular mode, accumulated leaked liquid fuel in the gaseous nozzle chamber of each fuel injector is purged and burned in the respective engine cylinder.

Abstract: A common rail fuel system includes a common rail supplied by an inlet metered high pressure pump and fluidly connected to a plurality of zero-leak fuel injectors. An electronic controller controls pressure in the common rail predominantly responsive to a rail pressure error when outside of an overshoot avoidance condition corresponding to the error being less than a first threshold and a time rate of change of the error being greater than a second threshold. Pressure in the common rail is controlled predominantly responsive to the time rate of change of the error during the overshoot avoidance condition.

Abstract: A method for fault diagnosis in a fuel injection system having first and second fuel injectors. The method includes initiating a current flow in the first and second fuel injectors. Further, a rise duration of the current flow to reach a threshold level is measured. The method further includes comparing the rise duration and a preset duration. The fuel injection system is controlled based on the comparison.