Engine torque estimating apparatus, engine torque estimating method, and engine control apparatus

An engine torque estimating method comprising:

• estimating a torque by calculating time series data of an estimated indicated torque, based on a crank angle having been extracted from an output of a crank angle sensor of an engine including a plurality of cylinders;
• extracting an estimated indicated torque-related value by extracting an estimated indicated torque-related value, for each of the cylinders, from the time series data of the estimated indicated torque, for each of the cylinders;
• and
• acquiring average indicated torque correct value by converting, for each of the cylinders, the estimated indicated torque-related value into an average indicated torque correct value having been calculated based on a cylinder internal state of an engine for an experiment, which is obtained from the engine for the experiment when the engine for the experiment was rotated, in correspondence to the estimated indicated torque-related value,
• wherein the estimated indicated torque-related value is one of,
• an estimated indicated torque amplitude that is a difference between a maximum value and a minimum value within a half-cycle of a rotation of a crank shaft in the time series data of the estimated indicated torque, and
• an estimated indicated torque integrated value corresponding to the half-cycle.

An engine control apparatus comprising:

• a processor;
• and
• a memory accessed by the processor,
• the processor performs,
• an engine torque estimating that calculates, based on a crank angle having been extracted from an output of a crank angle sensor of an engine including a plurality of cylinders, an average indicated torque correct value, for each of the cylinders;
• and
• an injection amount determining that determines a fuel injection amount, for each of the cylinders, so that the average indicated torque correct value for each of the cylinders matches a needed torque, wherein
• the engine torque estimating includes:
• estimating a torque by calculating time series data of an estimated indicated torque, based on the crank angle having been extracted from the output of the crank angle sensor of the engine including the plurality of cylinders;
• extracting an estimated indicated torque-related value by extracting an estimated indicated torque-related value, for each of the cylinders, from the time series data of the estimated indicated torque, for each of the cylinders;
• and
• acquiring average indicated torque correct value by converting, for each of the cylinders, the estimated indicated torque-related value into an average indicated torque correct value having been calculated based on a cylinder internal state of an engine for an experiment, which is obtained from the engine for the experiment when the engine for the experiment was rotated, in correspondence to the estimated indicated torque-related value,
• wherein the estimated indicated torque-related value is one of,
• an estimated indicated torque amplitude that is a difference between a maximum value and a minimum value within a half-cycle of a rotation of a crank shaft in the time series data of the estimated indicated torque, and
• an estimated indicated torque integrated value corresponding to the half-cycle.