Abstract: Methods and systems are provided for controlling fueling and mitigating knock in internal combustion engines, such as multi-fuel engines. In one example, a method may include monitoring a frequency of knock events corresponding to one or more engine cylinders, and dynamically increasing a substitution ratio while the frequency of knock events is less than a maximum action threshold. In some examples, the method may further include actively adjusting one or more engine operating conditions to decrease the substitution ratio responsive to a severity of knocking in the one or more engine cylinders being greater than or equal to a threshold severity.

Abstract: Methods and systems are provided for a multi-fuel engine. In one example, a method includes operating engines of rail vehicles at a desired substitution ratio to recharge an energy storage device of a rail vehicle operating in an all-electric mode to meet a requested total power.

Abstract: A shift detection system and method may monitor at least first and second operating parameters of a power supply system over time, and generate an adaptive model based on values of the first and second operating parameters. The adaptive model may include data points defined by the values of the first and second operating parameters. The data points may be grouped into bins according to designated ranges of the first operating parameter, and nodes may be calculated for individual bins based on the data points within the bins. An output function may be determined based on the nodes, and a shift incident may be detected based at least in part on an offset between the output function and recent values of the second operating parameter. A control signal may be generated in response to the shift incident to control the power supply system and/or notify an operator.

Abstract: Various methods and systems are provided for a multi-fuel capable engine. The system includes a liquid fuel system to deliver liquid fuel to an engine, a gaseous fuel system to deliver gaseous fuel to the engine, and a control system. The control system can control and test the liquid and gaseous fuel systems.

Abstract: Systems and methods are provided for diagnosing cylinders. In one example, a system includes an engine having a plurality of cylinders coupled to a crankshaft, a crankshaft speed sensor, and a controller. The controller is configured to receive a first output from the crankshaft speed sensor during nominal engine operation, receive a second output from the crankshaft speed sensor during engine operation where a fueling disturbance is introduced to a cylinder of the plurality of cylinders, indicate that the cylinder is unhealthy responsive to a difference between the first output and the second output being less than a threshold difference, and adjust one or more operating parameters of the engine in response to the indication.

Abstract: Various methods and systems are provided for a multi-fuel capable engine. The system includes a liquid fuel system to deliver liquid fuel to an engine, a gaseous fuel system to deliver gaseous fuel to the engine, and a control system. The control system can control and test the liquid and gaseous fuel systems.

Abstract: A system includes one or more sensors that generate sensor measurements representing a first parameter of one or more components of a power circuit. The system includes a control unit that obtains a reference rate of change value of the first parameter based at least in part on the sensor measurements over time. The control unit compares rates of change of monitored values of the sensor measurements over time to the reference rate of change value over time, and determines a deviation condition in response to the rate of change of a first monitored value of the sensor measurements differing from the reference rate of change value by more than a determined tolerance margin value. The control unit generates a control signal responsive to detecting the deviation condition to change an operating condition of at least one of the components of the power circuit.

Abstract: Methods and systems are provided for controlling fueling and mitigating knock in internal combustion engines, such as multi-fuel engines. In one example, a method may include monitoring a frequency of knock events corresponding to one or more engine cylinders, and dynamically increasing a substitution ratio while the frequency of knock events is less than a maximum action threshold. In some examples, the method may further include actively adjusting one or more engine operating conditions to decrease the substitution ratio responsive to a severity of knocking in the one or more engine cylinders being greater than or equal to a threshold severity.

Abstract: Various methods and systems are provided for a multi-fuel capable engine. The system includes a liquid fuel system to deliver liquid fuel to an engine, a gaseous fuel system to deliver gaseous fuel to the engine, and a control system. The control system can control and test the liquid and gaseous fuel systems.

Abstract: Various methods and systems are provided for correcting relative error between a gaseous fuel torque estimate and a liquid fuel torque estimate in a multi-fuel engine. A system (e.g., a system for an engine) may include a controller with computer readable instructions stored on non-transitory memory that when executed during operation of the engine cause the controller to: operate the engine at a first substitution ratio of gaseous fuel and liquid fuel; correct for relative error between a gaseous fuel to torque conversion factor and a liquid fuel to torque conversion factor; and upon correcting for the relative error, operate the engine at a second substitution ratio, higher than the first substitution ratio.

Abstract: Various methods and systems are provided for correcting relative error between a gaseous fuel torque estimate and a liquid fuel torque estimate in a multi-fuel engine. A system (e.g., a system for an engine) may include a controller with computer readable instructions stored on non-transitory memory that when executed during operation of the engine cause the controller to: operate the engine at a first substitution ratio of gaseous fuel and liquid fuel; correct for relative error between a gaseous fuel to torque conversion factor and a liquid fuel to torque conversion factor; and upon correcting for the relative error, operate the engine at a second substitution ratio, higher than the first substitution ratio.