摘要:
A system for protecting an internal combustion engine employing cooled recirculated exhaust gas (EGR) from excessive condensation includes an auxiliary emission control device (AECD) operable to determine when engine operating conditions correspond to a condensing condition resulting in condensation of water at the outlet of the EGR cooler and/or within the intake manifold or intake conduit of the engine. When such conditions occur, the AECD is operable to close the EGR valve and monitor engine operating conditions. When engine operating conditions no longer correspond to the condensing condition, control of the EGR valve is restored to an air handling system associated with the engine.
摘要:
A method and system for controlling an exhaust temperature for an internal combustion engine is disclosed. The method and system include determining a range of acceptable charge flows within the internal combustion engine to meet a desired exhaust temperature. The method and system further include controlling the charge flows to fall within the range. Control strategies to utilize the charge flow as a lever to control turbine outlet temperature are disclosed. These strategies utilize the inversion of the cylinder outlet temperature virtual sensor as well as a new turbine outlet temperature virtual sensor to determine the charge flow required to achieve the desired turbine outlet temperature given the current turbine inlet and outlet pressure, SOI, charge pressure, charge temperature, fueling, and engine speed.
摘要:
A system is disclosed for estimating the mass flow of recirculated exhaust gas (EGR) from an exhaust manifold to an intake manifold of an internal combustion engine via an EGR conduit disposed therebetween and a fraction of EGR attributable to a mass of charge flow entering the intake manifold. An engine controller is responsive to current values of various combinations of the engine exhaust temperature (ETE), intake manifold pressure (IMP), differential pressure (ΔP) across an EGR valve, and EGR valve position (EGRP) to determine an estimate of EGR mass flow. The controller is further operable to estimate EGR fraction as a function of the estimated EGR mass flow value, mass flow of charge entering the intake manifold, and engine speed.
摘要:
A charge limit manager arbitrates between desired EGR system and/or turbocharger behavior and the actual capabilities of EGR system and/or turbocharger control mechanisms under current operating conditions. In one embodiment, the charge limit manager includes three limiter blocks producing offset signals as separate functions of turbocharger compressor outlet temperature, turbocharger speed and pressure differential (&Dgr;P) across an EGR valve. A charge limit selector block is responsive to the offset values produced thereby, and also to commanded values of charge flow and EGR fraction as well as operating values of EGR valve position and &Dgr;P, to limit the charge flow and EGR fraction commands to controllable values. These values are preferably subtracted from actual or estimated values of charge flow and EGR fraction to produce charge flow and EGR fraction error values for use in controlling one or more EGR system and/or turbocharger swallowing capacity/efficiency control mechanisms.
摘要:
A system is provided for estimating engine exhaust temperature in accordance with an exhaust temperature model based on a number of engine operating parameters. In one embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, mass charge flow, default fuel command parameters, and a first set of model constants. In an alternative embodiment, the engine exhaust temperature model is based on current values of engine speed, intake manifold temperature, intake manifold pressure, mass charge flow, default fueling parameters, and a second set of model constants including a lower heating value of fuel constant.
摘要:
A system for controlling exhaust emissions produced by an internal combustion engine includes an engine controller having an emission manager configured to produce a base emission level cap command, corresponding to a maximum allowable emission level of the engine, as a function of at least altitude and ambient temperature. The emission manager may also include one or more auxiliary emission control devices (AECDs), and the emission manager is further operable in such cases to determine a maximum allowable emission level associated with each active AECD. A final emission level cap command is determined as a function of the base emission level cap command and the maximum allowable emission level associated with each active AECD. The emission manager is further operable to produce a protection state data structure that includes information relating to the operational status of each AECD.
摘要:
A system for controlling exhaust emissions produced by an internal combustion engine includes an engine controller having an emission manager configured to produce a base emission level cap command, corresponding to a maximum allowable emission level of the engine, as a function of at least altitude and ambient temperature. The emission manager may also include one or more auxiliary emission control devices (AECDs), and the emission manager is further operable in such cases to determine a maximum allowable emission level associated with each active AECD. A final emission level cap command is determined as a function of the base emission level cap command and the maximum allowable emission level associated with each active AECD. The emission manager is further operable to produce a protection state data structure that includes information relating to the operational status of each AECD.
摘要:
A combustion manager portion of an engine controller is responsive to ambient air density and engine temperature signals to schedule charge flow and EGR fraction commands. The combustion manager includes a data structure determination block operable to select an appropriate engine speed/engine fueling data structure based on air density and engine temperature information as well as on desired emissions level and engine operating state (i.e., steady state or transient) information. Charge flow and EGR fraction determination blocks are, in turn, responsive to current engine speed and engine fueling information to produce compute the EGR fraction and charge flow commands as a function of the selected engine speed/engine fueling data structures.
摘要:
A system and method for controlling an engine or machine at a remote unit from a central office, which may be a fixed location, contemplates a transmit/receive interface connected to the computer or microprocessor of the engine or machine controller. This interface is integrated with a communications module that is configured to establish communications with a World Wide Web server on the Internet. A similar system is established at the location of the central office connected to a computer controlled by a fleet owner/operator, for example. The fleet owner can upload machine control data or machine control application software to an intermediate digital file storage maintained by the Web server via the Internet. This data or application software can be accessed and downloaded at any time by the remote operator without any direct interface or communication with the central office. The remote machine controller includes a data entry device that allows the remote operator to issue commands to the Web server to upload or download information, input password or security information for access to the data in intermediate file storage, or leave messages for the central office. The transmit/receive interface at the remote unit includes means for receiving the downloaded information, determining whether the information is application data or application software, and updating the machine controller accordingly. In this manner, either specific data can be downloaded to modify the performance of the controlled machine, or entirely new application software or modified application software can be downloaded directly to the machine controller.
摘要:
The present invention allows the vehicle to be operated at higher than normally desired speeds during periods when there is a legitimate need for increased performance, such as downshifting in order to aid in climbing an uphill grade or accelerating with the goal of upshifting. Like the prior art systems, the present invention also imposes a maximum vehicle speed for all non-top gears, but only during steady state conditions (defined as a light engine load existing for a predetermined period of time). During transient conditions (discerned by recognizing gear changes and by high engine load conditions), the control system of the present invention provides lenience from the normal maximum vehicle speed limits for non-top gears. Such lenience provides for increased vehicle performance during periods when it is legitimately needed by the driver. During steady state conditions, the present invention prevents the use of non-top gear during high vehicle speed driving by limiting the vehicle road speed if the transmission is not in top gear.