摘要:
A method for air/fuel operation of an engine. The engine is supplied fuel from both a fuel purging system to purge fuel in a fuel supply and feed such purged fuel to an intake manifold of the engine and a fuel injection system to inject fuel from such fuel supply into a cylinder of such engine. The method includes producing a first air/fuel ratio control signal in accordance with measured exhaust gas oxygen emission from the engine; producing a second air/fuel ratio control signal in accordance with fuel transport delay through the fuel purging system; combining the first and second air/fuel ratio control signals into a composite control signal; and feeding such composite control signal to the fuel injection system. Producing the first air/fuel ratio control signal comprises determining fuel flow rate through the purge system. The purge system includes a valve, such valve passing the fuel in the purging system to the intake manifold at a rate relate to a duty cycle of a control signal fed to such valve and wherein the flow rate is determined in response to the duty cycle the control signal fed to the valve. The purge system includes a hydrocarbon sensor responsive to fuel in the purging system and wherein the first air/fuel ratio control signal is produced in accordance with an output of such sensor. The method includes determining a species of hydrocarbon in the fuel being purged and adjusting the first air/fuel ratio control signal in accordance with the determined species. The species determination comprises determining from the exhaust gas oxygen a deviation of the engine emissions from stoichiometry. The method includes providing a model of the engine. The model represents a relationship between: (1) a signal model LAMBSE, representative of estimated air/fuel ratio of the engine relative to a stoichiometric air/fuel ratio for the engine; and, (2) fuel injected into the cylinder of the engine. Exhaust gas oxygen emission from the engine is measured during operation of such engine. Actual LAMBSE produced by such engine during operation of such engine is produced as a function of such measured oxygen. The actual LAMBSE is compared with the model LAMBSE provided by the model in response to fuel injected into the engine to produce a model error signal. The fuel injected into the engine is adjusted in accordance with the error signal.
摘要:
A method for air/fuel operation of an engine. The method includes providing a model of the engine. The model represents a relationship between: (1) a signal model LAMBSE, representative of estimated air/fuel ratio of the engine relative to a stoichiometric air/fuel ratio for the engine; and, (2) fuel injected into the cylinder of the engine. Exhaust gas oxygen emission from the engine is measured during operation of such engine. Actual LAMBSE produced by such engine during operation of such engine is produced as a function of such measured oxygen. The actual LAMBSE is compared with the model LAMBSE provided by the model in response to fuel injected into the engine to produce a model error signal. The fuel injected into the engine is adjusted in accordance with the error signal.
摘要:
Cyclic variation in combustion of a lean burning engine is reduced by detecting an engine combustion event output such as torsional acceleration in a cylinder (i) at a combustion event (k), using the detected acceleration to predict a target acceleration for the cylinder at the next combustion event (k+1), modifying the target output by a correction term that is inversely proportional to the average phase of the combustion event output of cylinder (i) and calculating a control output such as fuel pulse width or spark timing necessary to achieve the target acceleration for cylinder (i) at combustion event (k+1) based on anti-correlation with the detected acceleration and spill-over effects from fueling.
摘要:
An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.
摘要:
An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.
摘要:
An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.
摘要:
A standardized microcontroller-based fuzzy logic processing module for generating control signal values in response to variable input signal values in accordance with constraints imposed by propositions or "rules" stored in memory in a standardized format. Each rule consists of one or more input conditions and an output directive. Each input signal and the output signal values are characterizable by their degree of membership in a predetermined number of fuzzy sets, each fuzzy set being defined by a membership function. Each input condition is composed of a reference to a particular input variable, which has been preprocessed into integer (whole number) normalized form and a reference to a membership function. Each output directive includes a reference to a further membership function. Each membership function is implemented by one of a three possible forms of standard membership data structures: a triangular function represented by three data points, a table lookup function represented by a two end data points and the points between these two end points, and an standard shape function composed of a set of data points and a set of reference points used to form a similar shape function by interpolation. Fuzzy logic processing is accomplished by determining the extent to which the input conditions are satisfied by the current values of the input signals in order to develop a rule strength value, and then performing a "center-of-gravity" determination based on the output membership function values of each satisfied rule integrated over the range of possible output signal values.
摘要:
An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.
摘要:
An accurate thermodynamic model of an Active Lean NOx (ALNC) Catalyst is presented. The model takes into account hydrocarbon storage and release mechanisms of the ALNC, as well as the degradation in the ALNC hydrocarbon conversion efficiency due to ageing, and thus provides a more accurate estimate of an exotherm generated by hydrocarbon combustion in the ALNC. The estimated exotherm can them be used to detect system degradation and identify components responsible for the degradation.
摘要:
A data communication system for providing data transmission between a plurality of individually addressable local computer networks, by utilizing single node switching across a common passive bus medium. The passive bus medium is characterized as having a plurality of separate conductors of limited length that are each commonly connected to individual bus interface circuits for each local computer network. Each bus interface circuit has a number of dedicated address data ports, message data ports and control ports that are connected to separate dedicated conductors of the passive bus medium for transmitting data to and receiving data from other local computer networks. Each message transmission of data on the passive bus medium is divided into a number of mini-packets each of which contain a number of parallely transmitted bits corresponding to the number of dedicated address and message conductors in the passive bus medium. Each mini-packet is separately transmitted on the passive bus medium and separately acknowledged by the designated receiving bus interface circuit. Mini-packets are of two types for each message. The first group of mini-packets precedes the second group and contains destination address in its header portion and word count information in its message portion. The second group constitutes the remainder of the message and each mini-packet of this group contains the source address in the header portion and message data in the message portion.