Supervisory model predictive controller for diesel engine emissions control

A system for controlling an engine airpath comprising:

• a processor communicatively coupled to a non-transitory computer-readable medium, wherein the non-transitory computer-readable medium stores instructions that, when executed by the processor, cause the processor to:
• receive an engine speed corresponding to a present engine speed, a fuel target corresponding to a request for torque from a driver and one or more state estimates generated by an estimator;
• predict over a prediction horizon a constraint violation in response to the engine speed, the fuel target, and the one or more state estimates using a prediction model;
• adjust an EGR rate target to a modified value when the constraint violation is predicted;
• maintain the EGR rate target at a nominal value when the constraint violation is not predicted;
• generate one or more actuator commands based on the EGR rate target, wherein the one or more actuator commands control one or more of an EGR throttle, an EGR valve, and a VGT such that an EGR rate of the engine airpath tracks the EGR rate target;
• and
• transmit the one or more actuator commands to a valve of an engine.

A vehicle comprising:

• a diesel engine comprising a diesel engine airpath;
• a sensor coupled to the diesel engine airpath;
• an actuator coupled to the diesel engine airpath;
• an electronic control unit comprising a processor and a non-transitory computer-readable medium, the electronic control unit communicatively coupled to the sensor and the actuator, and the non-transitory computer-readable medium stores instructions that, when executed by the processor, cause the processor to:
• receive an engine speed corresponding to a present engine speed, a fuel target corresponding to a request for torque from a driver and one or more state estimates generated by an estimator;
• predict, over a prediction horizon, a constraint violation in response to the engine speed, the fuel target, and the one or more state estimates;
• adjust an EGR rate target to a modified value when the constraint violation is predicted;
• maintain the EGR rate target at a nominal value when the constraint violation is not predicted;
• generate one or more actuator commands based on the EGR rate target, wherein the one or more actuator commands control the actuator such that an EGR rate of the diesel engine airpath tracks the EGR rate target;
• and
• transmit the one or more actuator commands to the actuator of the diesel engine.