An engine control system comprises: an engine 10 capable of switching between a reduced-cylinder operation mode in which combustion is stopped in a part of a plurality of cylinders 2 and an all-cylinder operation mode in which combustion is performed in all the plurality of cylinders 2; and a PCM 50 configured to stop fuel supply to the cylinders 2 when a given fuel cut-off condition is satisfied. The PCM 50 is operable, during a transition from a state in which the engine 10 is operated in the reduced-cylinder operation mode to a state in which the fuel cut-off condition is satisfied, to stop the fuel supply to the cylinders 2 at a timing earlier than that during a transition from a state in which the engine 10 is operated in the all-cylinder operation mode to the state in which the fuel cut-off condition is satisfied.

The present disclosure relates to an engine in which compression and expansion is performed in the same cylinder. Also disclosed is a microprocessor for controlling the state of various valves in the cylinderincluding an intake valve, a transfer valve, and an exhaust valveto cause a compression or expansion to occur. A compression tank is provided for receiving, via the transfer valve, compressed air, which may be retrieved during an expansion (combustion) cycle. Compressed air for from multiple consecutive compressions may be stored in the tank and retrieved later, including for multiple consecutive expansions. Compression and expansion are not required to occur in any fixed or predetermined pattern and the microprocessor may evaluate vehicle sensors to determine a power demand, and cause compression or expansion to occur depending on the given power demand.

The present disclosure relates to an engine in which compression and expansion is performed in the same cylinder. Also disclosed is a microprocessor for controlling the state of various valves in the cylinderincluding an intake valve, a transfer valve, and an exhaust valveto cause a compression or expansion to occur. A compression tank is provided for receiving, via the transfer valve, compressed air, which may be retrieved during an expansion (combustion) cycle. Compressed air for from multiple consecutive compressions may be stored in the tank and retrieved later, including for multiple consecutive expansions. Compression and expansion are not required to occur in any fixed or predetermined pattern and the microprocessor may evaluate vehicle sensors to determine a power demand, and cause compression or expansion to occur depending on the given power demand.

A method of determining an amount of fuel wasted by a vehicle due to sub-optimal performance of at least one component of the vehicle includes receiving information about operation of the vehicle from at least one sensor positioned on the vehicle, categorizing, with a processor, a fuel use by the vehicle as a normal fuel use or a wasted fuel use due to the at least one component performing at a sub-optimal level by comparing the received information to expected information from the at least one sensor when the vehicle is operating at optimal performance, and determining, with the processor, the amount of fuel wasted due to the at least one component operating at the sub-optimal level based on categorized fuel use.

A method of determining an amount of fuel wasted by a vehicle due to sub-optimal performance of at least one component of the vehicle includes receiving information about operation of the vehicle from at least one sensor positioned on the vehicle, categorizing, with a processor, a fuel use by the vehicle as a normal fuel use or a wasted fuel use due to the at least one component performing at a sub-optimal level by comparing the received information to expected information from the at least one sensor when the vehicle is operating at optimal performance, and determining, with the processor, the amount of fuel wasted due to the at least one component operating at the sub-optimal level based on categorized fuel use.

An estimation method to determine the concentration of recirculated exhaust gas present in a cylinder of an internal combustion engine; the concentrations of recirculated exhaust gas in a gas mixture flowing through an intake duct are periodically stored in a buffer; a first instant is determined, in which a programming of a following combustion in the cylinder is carried out; an advance time is determined, which elapses between the first instant and a second instant in the future, in which air will be taken into the cylinder for the following combustion in the cylinder; a transport time is determined; a third instant in the past is determined by subtracting from the first instant an amount of time which is equal to the difference between the transport time and the advance time; and the concentration of recirculated exhaust gas present in the cylinder in the second instant is estimated depending on a concentration of recirculated exhaust gas contained in the buffer (30) and corresponding to the third instant.

An estimation method to determine the concentration of recirculated exhaust gas present in a cylinder of an internal combustion engine; the concentrations of recirculated exhaust gas in a gas mixture flowing through an intake duct are periodically stored in a buffer; a first instant is determined, in which a programming of a following combustion in the cylinder is carried out; an advance time is determined, which elapses between the first instant and a second instant in the future, in which air will be taken into the cylinder for the following combustion in the cylinder; a transport time is determined; a third instant in the past is determined by subtracting from the first instant an amount of time which is equal to the difference between the transport time and the advance time; and the concentration of recirculated exhaust gas present in the cylinder in the second instant is estimated depending on a concentration of recirculated exhaust gas contained in the buffer (30) and corresponding to the third instant.

A control device of an internal combustion engine is configured to output a predicted value of an output parameter by using a learning model if actually measured values of input parameters are input, control the internal combustion engine based on the predicted value of the output parameter, learn the learning model by using a gradient method and by using a combination of actually measured values of the input parameters and an actually measured value of the output parameter as teacher data, and adjust the learning rate so that the learning is performed by a smaller learning rate when an amount of noise superposed on an actually measured value of at least one parameter among the input parameters and the output parameter is relatively large compared with when the amount of noise superposed on the actually measured value of the parameter is relatively small.

A control device of an internal combustion engine is configured to output a predicted value of an output parameter by using a learning model if actually measured values of input parameters are input, control the internal combustion engine based on the predicted value of the output parameter, learn the learning model by using a gradient method and by using a combination of actually measured values of the input parameters and an actually measured value of the output parameter as teacher data, and adjust the learning rate so that the learning is performed by a smaller learning rate when an amount of noise superposed on an actually measured value of at least one parameter among the input parameters and the output parameter is relatively large compared with when the amount of noise superposed on the actually measured value of the parameter is relatively small.

An operation management device includes a state acquiring unit that acquires a measurement value of a first state amount indicating an operation state of a power generation plant, a state updating unit that updates an estimation value of a second state amount, which indicates the operation state of the power generation plant and is a state amount different from the first state amount, based on the measurement value of the first state amount, and a managing unit that manages the operation state of the power generation plant based on the estimation value of the second state amount.