Arbitration strategy for slow response and fast response torque requests

Abstract

The present disclosure relates to systems and methods for managing engine output. A method includes receiving at least one of a torque input and an acceleration input; generating a torque request for an engine; receiving the torque request; and determining an amount of the torque request that can be provided by a fast response actuator including a spark timing actuator based on a governed torque fraction value based on existing operating conditions of the spark timing actuator and a torque fraction value indicative of a total torque request value and an anticipated future torque demand value. The method includes managing the spark timing actuator to produce the amount of torque; determining a remaining amount of the torque request that cannot be provided the fast response actuator based on an existing operating condition of the engine; and commanding a slow response actuator to provide the remaining amount of the torque request.

What is claimed is: 
     
         1 . A method for managing engine output, comprising:
 receiving, by a control system, at least one of a torque input and an acceleration input;   generating, by the control system, a torque request for an engine;   receiving, by the control system, the torque request;   determining, by the control system, an amount of the torque request that can be provided by a fast response actuator based on a governed torque fraction value and a torque fraction value, the fast response actuator including a spark timing actuator, wherein the governed torque fraction value is based on information indicative of existing operating conditions of the spark timing actuator, and wherein the torque fraction value is indicative of a total torque request value and an anticipated future torque demand value;   managing, by the control system, the spark timing actuator to produce the amount of torque; and   determining, by the control system, a remaining amount of the torque request that cannot be provided the fast response actuator based on an existing operating condition of the engine; and   commanding, by the control system, a slow response actuator to provide the remaining amount of the torque request.   
     
     
         2 . The method of  claim 1 , wherein the slow response actuator comprises an air actuator. 
     
     
         3 . The method of  claim 1 , wherein managing the spark timing comprises spark retardation. 
     
     
         4 . The method of  claim 3 , wherein managing the spark timing comprises bringing the spark timing actuator to an approximate middle of a spark timing range and sacrificing engine efficiency for engine responsiveness. 
     
     
         5 . The method of  claim 1 , wherein determining the amount of the torque request that can be provided by a fast response actuator is selectively enabled based on an optimization index. 
     
     
         6 . The method of  claim 1 , wherein determining the amount of torque that can be provided by the fast response actuator comprises managing fuel injection from one combustion event to the next. 
     
     
         7 . The method of  claim 1 , further comprising identifying and tracking, by the control system, the source of the torque requests. 
     
     
         8 . The method of  claim 7 , further comprising correlating, by the control system, the ultimate engine operating demands with the identification of the torque request and the specifications of a given actuator. 
     
     
         9 . The method of  claim 1 , wherein the torque fraction value is determined based on an indicated torque value that is indicative of the total torque request and a losses torque, divided by the sum of the indicated torque value and a reserve torque value indicative of the anticipated future torque demand value. 
     
     
         10 . A method for improving torque actuation response, comprising:
 actuating fuel and air actuators to achieve a built-up torque reserve;   concurrent with actuating the fuel and air actuators, retarding spark timing from an optimal spark timing to achieve a desired engine output torque.   
     
     
         11 . The method of  claim 10 , wherein retarding spark timing brings a spark actuator to the middle of a spark timing range for bi-directional control and sacrifices engine efficiency for engine responsiveness. 
     
     
         12 . The method of  claim 10 , wherein the built-up torque reserve can be achieved by running the engine lean thereby reducing the spark retard and minimizing efficiency loss. 
     
     
         13 . The method of  claim 10 , wherein the built-up torque reserve can be achieved by use of various combinations of relatively fast and relatively slow torque actuators. 
     
     
         14 . The method of  claim 10 , wherein the relatively fast actuators include fuel injection and spark timing and the relatively slow actuators include air actuators. 
     
     
         15 . A system for improving torque actuation response, comprising:
 a control system configured to:
 actuate fuel and air actuators to achieve a built-up torque reserve; and 
 retard spark timing from an optimal spark timing to achieve a desired engine output torque concurrent with actuating the fuel and air actuators. 
   
     
     
         16 . The system of  claim 15 , wherein retarding spark timing brings a spark actuator to the middle of a spark timing range for bi-directional control and sacrifices engine efficiency for engine responsiveness. 
     
     
         17 . The system of  claim 15 , wherein the built-up torque reserve is configured to meet anticipated future or supplemental torque demands from one or more vehicle systems. 
     
     
         18 . The system of  claim 15 , wherein the control system is configured to run the engine lean to achieve the built-up torque reserve, thereby reducing the spark retard and minimizing efficiency loss. 
     
     
         19 . The system of  claim 15 , wherein the control system is configured to actuate one or more of relatively fast torque actuators and relatively slow torque actuators to achieve the built-up torque reserve. 
     
     
         20 . The system of  claim 19 , wherein the relatively fast actuators include fuel injection and spark timing and the relatively slow actuators include air actuators.