Diagnosing and remediating fuel injection drift utilizing fuel rail pressure measurements
A fuel injection system for an internal combustion engine is provided. The fuel injection system comprises a primary fuel injector, a sensor, at least one secondary fuel injector and a controller. The primary fuel injector is configured to inject fuel into an ignition chamber of the internal combustion engine. The sensor is coupled to the primary fuel injector, wherein the sensor is configured to sense a fuel pressure of the fuel being injected by the primary fuel injector throughout each injection cycle of the primary fuel injector. The at least one secondary fuel injector is configured to inject fuel into a respective ignition chamber of the internal combustion engine. The controller is configured to receive data indicative of the fuel pressure value throughout each injection cycle. The controller is configured to determine a fuel quantity drift parameter over a plurality of fuel injection cycles based on the data indicative of the fuel pressure value. The controller is configured to adjust a fuel quantity delivered by the primary fuel injector and each secondary fuel injector based on the fuel quantity drift parameter.
1 . A fuel injection system for an internal combustion engine comprising:
a primary fuel injector configured to inject fuel into an ignition chamber of the internal combustion engine for a plurality of injection cycles of the primary fuel injector;
a sensor coupled to the primary fuel injector, the sensor configured detect a pressure drop of the fuel upstream of the primary fuel injector upon each injection cycle of the primary fuel injector;
at least one secondary fuel injector configured to inject fuel into a respective ignition chamber of the internal combustion engine;
a controller configured to:
receive data indicative of changes in the pressure drop for the plurality of injection cycles for only the primary fuel injector;
determine a fuel quantity drift parameter based on the data indicative of the changes in the pressure drop over the plurality of injection cycles of the primary fuel injector;
determine a secondary fuel quantity drift parameter for the at least one secondary fuel injector based at least in part on the changes in the pressure drop over the plurality of injection cycles of the primary fuel injector;
adjust a fuel quantity delivered by the primary fuel injector and each secondary fuel injector based on the fuel quantity drift parameter and the secondary fuel quantity drift parameter;
wherein the controller is configured to calculate a moving average based on the data indicative of the changes in the pressure drop over the plurality of injection cycles for the primary fuel injector;
wherein the controller is configured to determine the fuel quantity drift parameter based on the moving average; and
wherein the controller is configured to determine the secondary fuel quantity drift parameter for the at least one secondary fuel injector based at least in part on the moving average.
2 . A fuel injection system according to claim 1 , wherein the controller is configured to adjust a fuel quantity delivered by the primary fuel injector and each secondary injector by adjusting an energisation period for each fuel injector based on the fuel quantity drift parameter.
3 . A fuel injection system according to claim 1 , wherein the controller is configured to adjust a fuel quantity delivered by the primary fuel injector and each secondary injector by adjusting a start of injection timing and/or an end of injection timing for each fuel injector based on the fuel quantity drift parameter.
4 . A fuel injection system according to claim 1 , wherein the sensor is integrated with the primary fuel injector.
5 . A fuel injection system according to claim 1 , wherein the primary fuel injector is connected to a fuel rail of the internal combustion engine by a fuel pipe, wherein the sensor is configured to sense a fuel pressure of the fuel in the fuel pipe.
6 . A fuel injection system according to claim 1 , wherein the fuel injection system comprises a first secondary fuel injector and a second secondary fuel injector, wherein the controller is configured to:
adjust a fuel quantity delivered by the first secondary fuel injector based on the fuel quantity drift parameter and a first weight associated with the first secondary fuel injector; and
adjust a fuel quantity delivered by the second secondary fuel injector based on the fuel quantity drift parameter and a second weight associated with the second secondary fuel injector.
7 . A fuel injection system according to claim 1 , wherein the fuel injection system further comprises a cylinder sensor coupled to a cylinder of the internal combustion engine associated with the primary fuel injector, the cylinder sensor configured to sense a cylinder pressure and/or a combustion timing of the cylinder, and the controller is configured to receive data indicative of the cylinder pressure and/or combustion timing, and to determine the fuel quantity drift parameter over the plurality of injection cycles based on the data indicative of changes in the pressure drop for the plurality of injection cycles for and the data indicative of the cylinder pressure and/or combustion timing.
8 . A fuel injection system according to claim 1 , wherein the controller is configured to cause the primary fuel injector and the at least one secondary fuel injector to perform a first fuel injection cycle and a second fuel injection cycle for each cycle of the internal combustion engine.
9 . A fuel injection system according to claim 8 , wherein the controller is configured to adjust a fuel quantity delivered by the primary fuel injector and the at least one secondary fuel injector based on the fuel quantity drift parameter and a first weight associated with the first fuel injection cycle; and adjust a fuel quantity delivered by the primary fuel injector and the at least one secondary fuel injector based on the fuel quantity drift parameter and a second weight associated with the second fuel injection cycle.
10 . A fuel injection system according to claim 1 , wherein the fuel injection system is provided as part of diesel internal combustion engine, or an ammonia internal combustion engine.
11 . A computer program product configured to use the fuel injection system of claim 1 .
12 . A computer-readable storage medium having the computer program product of claim 11 stored thereon.
13 . A kit of parts for a fuel injection system of an internal combustion engine comprising a primary fuel injector and at least one secondary fuel injector, the kit of parts comprising:
a sensor configured to be coupled to a primary fuel injector of the internal combustion engine, the sensor configured to detect a pressure drop of fuel upstream of the primary fuel injector upon each injection cycle of the primary fuel injector;
a controller for controlling the fuel injection system, the controller configured to:
receive data indicative of a changes in the pressure drop for a plurality of injection cycles for only the primary fuel injector;
determine a fuel quantity drift parameter over the plurality of injection cycles based on the data indicative of the changes in the pressure drop over the plurality of injection cycles of the primary fuel injector;
determine a secondary fuel quantity drift parameter for the at least one secondary fuel injector based at least in part on the changes in the pressure drop over the plurality of injection cycles of the primary fuel injector; and
adjust a fuel quantity delivered by the primary fuel injector and each secondary fuel injector based on the fuel quantity drift parameter and the secondary fuel quantity drift parameter;
wherein the controller is configured to calculate a moving average based on the data indicative of the changes in the pressure drop over the plurality of injection cycles for the primary fuel injector;
wherein the controller is configured to determine the fuel quantity drift parameter based on the moving average; and
wherein the controller is configured to determine the secondary fuel quantity drift parameter for the at least one secondary fuel injector based at least in part on the moving average.
14 . A kit of parts according to claim 13 , wherein the sensor is provided as part of a primary fuel injector for the internal combustion engine, or as part of fuel pipe configured to supply fuel to the primary fuel injector of the internal combustion engine.
15 . A computer program product configured to use the kit of parts of claim 13 when installed on an internal combustion engine.
16 . A method of controlling a fuel injection system of an internal combustion engine comprising:
injecting fuel into an ignition chamber of the internal combustion engine using a primary fuel injector for a plurality of injection cycles of the primary fuel injector,
detecting, via a sensor coupled to the primary fuel injector, a pressure drop of the fuel upstream of the primary fuel injector upon each injection cycle of the primary fuel injector;
injecting fuel into a respective ignition chamber of the internal combustion engine using at least one secondary fuel injector;
receiving data at a controller, the data indicative of changes in the pressure drop for the plurality of injection cycles for only the primary fuel injector;
calculating a moving average based on the data indicative of the changes in the pressure drop over the plurality of injection cycles for the primary fuel injector;
determining a fuel quantity drift parameter based on the moving average;
determining a secondary fuel quantity drift parameter for the at least one secondary fuel injector based at least in part on the moving average; and
adjusting a fuel quantity delivered by the primary fuel injector and each secondary fuel injector based on the fuel quantity drift parameter and the secondary fuel quantity drift parameter.
17 . A computer program product configured to perform the method of claim 16 .