Abstract: An engine control system includes: a normalization module configured to normalize, to within a predetermined range of values, a spark timing of an engine and at least one other parameter of the engine, thereby producing a normalized spark timing and at least one normalized other parameter, respectively; a processing module configured to generate a sigmoidal spark timing by applying, to the normalized spark timing, one of (a) a sigmoidal function and a sinusoidal function; and an estimation module configured to estimate a torque output of the engine based on the normalized spark timing and the at least one normalized other parameter using a mathematical model.

Abstract: An engine control system includes: a normalization module configured to normalize, to within a predetermined range of values, a spark timing of an engine and at least one other parameter of the engine, thereby producing a normalized spark timing and at least one normalized other parameter, respectively; a processing module configured to generate a sigmoidal spark timing by applying, to the normalized spark timing, one of (a) a sigmoidal function and a sinusoidal function; and an estimation module configured to estimate a torque output of the engine based on the normalized spark timing and the at least one normalized other parameter using a mathematical model.

Abstract: A torque requesting module generates a torque request for an engine based on driver input. A model predictive control (MPC) module: identifies sets of possible target values based on the torque request, each of the sets of possible target values including target effective throttle area percentage; determines predicted operating parameters for the sets of possible target values, respectively; determines cost values for the sets of possible target values, respectively; selects one of the sets of possible target values based on the cost values; and sets target values based on the possible target values of the selected one of the sets, respectively, the target values including a target pressure ratio across the throttle valve. A target area module determines a target opening area of the throttle valve based on the target effective throttle area percentage ratio. A throttle actuator module controls the throttle valve based on the target opening.

Abstract: A system according to the principles of the present disclosure includes a first burn duration module and a spark control module. The first burn duration module determines a first duration of at least a portion of a fuel burn within a cylinder of an engine from a first time when a first predetermined percentage of a mass of fuel within the cylinder is burned to a second time when a second predetermined percentage of the fuel mass is burned. The spark control module controls a spark plug to adjust spark timing of the cylinder based on the first burn duration.

Abstract: An engine control system of a vehicle includes an estimation module and an actuator module. The estimation module estimates a crankshaft angle where 50 percent of a mass of fuel is burned during a combustion event based on: a combustion speed when a crankshaft of an engine is at a predetermined position during the combustion event; an engine speed; a mass of air per cylinder (APC); a spark timing; and a predetermined spark timing. The actuator module controls an engine actuator based on the crankshaft angle where 50 percent of the mass of fuel is burned during the combustion event.

Abstract: A parameter determination system includes first and second difference modules, a ratio module, and an M index module. The first difference module determines a first crankshaft angle of a combustion event of an engine, determines a second crankshaft angle of the combustion event of the engine, and determines a first difference between the first and second crankshaft angles. The second difference module determines a third crankshaft angle of the combustion event of the engine, determines a fourth crankshaft angle of the combustion event of the engine, and determines a second difference between the third and fourth crankshaft angles. The ratio module determines a ratio of the first difference to the second difference. The M index module determines an M index value for the Wiebe function based on the ratio and displays the M index value on a display.

Abstract: A system according to the principles of the present disclosure includes a first burn duration module and a spark control module. The first burn duration module determines a first duration of at least a portion of a fuel burn within a cylinder of an engine from a first time when a first predetermined percentage of a mass of fuel within the cylinder is burned to a second time when a second predetermined percentage of the fuel mass is burned. The spark control module controls a spark plug to adjust spark timing of the cylinder based on the first burn duration.

Abstract: An engine control system of a vehicle includes an estimation module and an actuator module. The estimation module estimates a crankshaft angle where 50 percent of a mass of fuel is burned during a combustion event based on: a combustion speed when a crankshaft of an engine is at a predetermined position during the combustion event; an engine speed; a mass of air per cylinder (APC); a spark timing; and a predetermined spark timing. The actuator module controls an engine actuator based on the crankshaft angle where 50 percent of the mass of fuel is burned during the combustion event.

Abstract: A parameter determination system includes first and second difference modules, a ratio module, and an M index module. The first difference module determines a first crankshaft angle of a combustion event of an engine, determines a second crankshaft angle of the combustion event of the engine, and determines a first difference between the first and second crankshaft angles. The second difference module determines a third crankshaft angle of the combustion event of the engine, determines a fourth crankshaft angle of the combustion event of the engine, and determines a second difference between the third and fourth crankshaft angles. The ratio module determines a ratio of the first difference to the second difference. The M index module determines an M index value for the Wiebe function based on the ratio and displays the M index value on a display.

Abstract: A method for operating a spark-ignition internal combustion engine includes controlling spark ignition timing responsive to a combustion charge flame speed corresponding to an engine operating point and a commanded air/fuel ratio associated with an operator torque request.

Abstract: A control system and method of controlling operation of an internal combustion engine includes a load determination module that determines an engine load, an equivalence ratio module that determines an equivalence ratio, a correction factor module that generates a correction factor based on the engine load, the equivalence ratio, and the engine speed and an engine operation module that regulates operation of the engine based on the correction factor.

Abstract: A method for operating a spark-ignition internal combustion engine includes controlling spark ignition timing responsive to a combustion charge flame speed corresponding to an engine operating point and a commanded air/fuel ratio associated with an operator torque request.

Abstract: A control system and method of controlling operation of an internal combustion engine includes a load determination module that determines an engine load, an equivalence ratio module that determines an equivalence ratio, a correction factor module that generates a correction factor based on the engine load, the equivalence ratio, and the engine speed and an engine operation module that regulates operation of the engine based on the correction factor.

Abstract: A robust multi-criteria minimum timing for the best torque (MBT) timing estimation method and apparatus utilizes different ionization signal waveforms that are generated under different engine operating conditions. The MBT timing criteria is calculated based upon both ionization and analog derivative ionization. Multiple MBT timing criteria are determined and combined to increase the reliability and robustness of MBT timing estimation based upon spark plug ionization signal waveforms. In a preferred embodiment, a combination of the MBT timing estimation criteria comprises a maximum flame acceleration location, a 50% burn location, and a second peak location.

Abstract: This feature of the present invention comprises a system and method of controlling exhaust gas recirculation (EGR) based on a measure combustion stability measure. The combustion stability measure is obtained by determining the integration duration of the engine ionization signal, i.e., the crank angle at which the integral of the ionization signal reaches a specified percentage of its total. The present invention uses the integration duration to control the maximum EGR rate of the engine in a closed loop while maintaining the combustion stability of an internal combustion engine.

Abstract: This feature of the present invention comprises a method and apparatus which uses an ionization signal to optimize the air to fuel ratio AFR of the combustion mixture when the engine is operated at wide open throttle (WOT). This feature of the present invention optimizes the air to fuel ratio AFR on-line using the relationship between an air to fuel ratio AFR index CAFR and the air to fuel ratio AFR. In a preferred embodiment, the real-time control strategy adjusts the engine air to fuel ratio AFR based upon an air to fuel ratio AFR gradient parameter.

Abstract: This feature of the present invention comprises an ignition diagnostics and feedback control system based upon detected ionization current in an individual cylinder. The system is divided into two subsystems: an ignition diagnostics subsystem and an ignition feedback control system subsystem. The ignition diagnostics subsystem comprises an ignition system diagnostics, a misfire detector, a knock detector, and a robust multi-criteria minimum timing for best torque MBT timing estimator. The ionization feedback control subsystem comprises five main subsystems: a closed loop cold start retard spark control using ionization feedback, a closed loop MBT timing control using ionization feedback, a closed-loop individual cylinder air to fuel ratio balancing control system, an optimal wide open throttle air/fuel ratio control, and an exhaust gas control using a spark plug ionization signal.

Abstract: This feature of the present invention comprises a method and apparatus to retard the spark time. As a result, the catalyst heats up quickly during the cold start. The retard spark control method of the present invention uses a closed loop to adjust the engine retard limit during an engine cold start to retard the engine spark as much as possible without engine misfire and with minimum partial burn. The increased exhaust temperature heats up the catalyst more quickly than conventional open loop approaches, which as a result, reduces hydrocarbon emissions. The closed loop retard spark control using ionization current feedback consists of four major components or functions, an error and gain generator, a proportional and integration control processing block, a default spark timing processor, and an adaptive learning apparatus.

Abstract: This feature of the present invention is a robust multi-criteria minimum timing for the best torque (MBT) timing estimation method and apparatus utilizing different ionization signal waveforms that are generated under different engine operating conditions. This feature of the present invention determines and combines multiple MBT timing criteria to increase the reliability and robustness of MBT timing estimation based upon spark plug ionization signal waveforms. In a preferred embodiment, the present invention combines MBT timing estimation criteria comprising a maximum flame acceleration location, a 50% burn location, and a second peak location.

Abstract: The present feature of the invention comprises a method and apparatus for determining cylinder ID. When a cylinder is compressed, the resistance increases across the spark plug gap. Thus, if a spark coil is only partially charged before activation of the spark, the air gap is not broken down and no ignition occurs in the cylinder in compression. The failure of a spark plug to spark is reflected in the ionization signal. In a preferred embodiment, the dwell time is selected so that the spark plug located in a cylinder that is not in compression will spark, while a spark plug in a cylinder that is in compression will not. The cylinder in compression will output an ionization signal with a shorter duration than a cylinder not in compression. In a preferred embodiment, two methods are used to calculate the duration of the spark, edge detection and integration.