Combustion phasing control methodology in HCCI combustion
AssigneeGM Global Technology Operations LLC
InventorsHanho Yun, Nicole Wermuth, Paul M. Najt, Jun-Mo Kang, Chen-Fang Chang
Life of this patent
Estimating the term…
Abstract
Controlling combustion in a spark-ignition direction-injection internal combustion engine includes providing an initial injected fuel mass timing and an initial spark ignition timing. A combustion phasing error is monitored and compared with each of the initial injected fuel mass timing and the initial spark ignition timing. An adjusted injected fuel mass timing and an adjusted desired spark ignition timing is determined based on the comparing for maintaining a desired combustion phasing.
Claims12
A method for controlling combustion in a spark-ignition direct-injection internal combustion engine, including an engine controller, a spark-ignition system and a fuel injector, comprising:
- providing an initial injected fuel mass timing;
- providing a respective upper bound for each of the initial injected fuel mass timing and an initial spark ignition timing corresponding to respective crank angle locations having most advanced timings acceptable for avoiding excessive combustion noise at a desired engine load;
- providing a respective lower bound for each of the initial injected fuel mass timing and the initial spark ignition timing corresponding to respective crank angle locations having most retarded timings acceptable for avoiding combustion stability deterioration at the desired engine load;
- adjusting the lower bounds for the initial injected fuel mass timing and the initial spark ignition timing based on an intake O2 concentration error, the intake O2 concentration error based on a deviation between a monitored O2 concentration from a previous combustion cycle and a desired intake O2 concentration;
- monitoring a combustion phasing error based on deviations between a monitored combustion phasing from a previous cycle and a desired combustion phasing;
- generating a bounded control signal associated with the monitored combustion phasing error and defined by an upper bound and a lower bound;
- determining an adjusted fuel mass timing comprising interpolating between the upper and lower bounds for the initial injected fuel mass timing based on the upper and lower bounds of the generated bounded control signal associated with the monitored combustion phasing error;
- determining an adjusted spark ignition timing comprising interpolating between the upper and lower bounds for the initial spark ignition timing based on the upper and lower bounds of the generated bounded control signal associated with the monitored combustion phasing error;
- and
- controlling the spark-ignition system and the fuel injector with the determined adjusted fuel mass timing and the determined adjusted spark ignition timing.
A method for controlling combustion in a spark-ignition direct-injection internal combustion engine, including an engine controller, a spark-ignition system and a fuel injector, comprising:
- providing initial combustion initiation timings having respective most advanced and most retarded timing limits comprising:
- providing an initial injected fuel mass timing having most advanced and most retarded timing limits at a desired engine load, and
- providing most advanced and most retarded initial spark ignition timing limits at the desired engine load;
- adjusting the most retarded timing limits for the initial injected fuel mass timing and the initial spark ignition timing based on an intake O2 concentration error, the intake O2 concentration error based on a deviation between a monitored O2 concentration from a previous combustion cycle and a desired intake O2 concentration;
- monitoring combustion phasing from the previous combustion cycle and a desired combustion phasing to determine a combustion phasing error;
- generating a bounded control signal associated with the determined combustion phasing error and defined by an upper bound and a lower bound;
- interpolating between the respective most advanced and most retarded timing limits based on the upper and lower bounds of the generated bounded control signal associated with the determined combustion phasing error to determine adjusted combustion initiation timings comprising an adjusted injected fuel mass timing and an adjusted spark ignition timing;
- utilizing the adjusted combustion initiation timings to control the monitored combustion phasing to converge toward the desired combustion phasing, comprising controlling the spark-ignition system and the fuel injector with the adjusted combustion initiation timings.
Dependencies are inferred from the claim text.