A premixed charge compression ignition engine, and a control system, is provided which effectively initiates combustion by compression ignition and maintains stable combustion while achieving extremely low nitrous oxide emissions, good overall efficiency and acceptable combustion noise and cylinder pressures. The present engine and control system effectively controls the combustion history, that is, the time at which combustion occurs, the rate of combustion, the duration of combustion and/or the completeness of combustion, by controlling the operation of certain control variables providing temperature control, pressure control, control of the mixture's autoignition properties and equivalence ratio control. The combustion control system provides active feedback control of the combustion event and includes a sensor, e.g. pressure sensor, for detecting an engine operating condition indicative of the combustion history, e.g. the start of combustion, and generating an associated engine operating condition signal. A processor receives the signal and generates control signals based on the engine operating condition signal for controlling various engine components to control the temperature, pressure, equivalence ratio and/or autoignition properties so as to variably control the combustion history of future combustion events to achieve stable, low emission combustion in each cylinder and combustion balancing between the cylinders.

Premixed charge compression ignition engine with optimal combustion control

A number of embodiments of engine controls and engine control methods that employ instantaneous rate of combustion is the combustion chamber at a sensed parameter. Rate of combustion is determined by a linear equation based upon data arrived from combustion chamber pressures. The system is adapted to operate under different control modes so as to provide specific control for normal running, lean burn, maximum torque, cold starting, transient conditions, and/or knock control. The desired rate of combustion is achieved by engine control adjustments.

Engine control system and method

A method of controlling combustion in an homogenous charge compression ignition engine through indirect mechanisms. The method utilizes a predictive model so that combustion can be controlled over a wide range of operating conditions while maintaining optimum operation with respect to efficiency and emissions. The methods include an adaptive aspect, which allows the predictive model to be updated if deemed necessary. Furthermore, the methods include a model with a plurality of control modes. A control mode can be chosen to optimize the engine for one of a plurality of output characteristics, including response time, efficiency, or emissions characteristics.

A method of controlling combustion in a homogenous charge compression ignition engine

An engine output control method for a vehicle having a drive by wire engine system responsive to a desired engine torque signal. The method comprises the steps of generating a driver demanded acceleration value corresponding to an accelerator pedal position input, and generating a gear value as a function of a vehicle speed value and the driver demanded acceleration value. The method also derives a driveline torque demand comprising an inertial model torque value of the vehicle driveline corresponding to the driver demanded acceleration and the gear value, and a dynamic transmission model torque value for the gear value. The resulting torque demand is then passed through an inverse torque converter model to generate a demanded engine torque. The resulting demanded engine torque value is then used to control the engine output. In this way, the present method accounts for the transmission and driveline dynamics in an acceleration-based engine control scheme.

Engine output controller

An apparatus and methods for effectively determining the start of combustion in a cylinder of an internal combustion engine where the start of combustion is calculated by obtaining cylinder pressure data (P), processing the cylinder pressure data (P) into a processed pressure value indicative of the occurrence of SOC, comparing the processed pressure value to a predetermined threshold value, if the processed pressure value crosses the predetermined threshold value, determining that SOC has occurred, and calculating a crank shaft location at which the predetermined threshold value was crossed by the processed pressure value thereby identifying the crank shaft location at which SOC occurred. In alternative embodiments, optional steps may be provided including a verification step, a windowing step, a filtering step, determining occurrence of misfire, and determining occurrence of retarded timing.

Apparatus and methods for determining start of combustion for an internal combustion engine

The control system of the invention is associated with an engine provided with means for measuring one or several parameters including pressures (in the cylinder, induction pressure, exhaust pressure) for each cylinder, acceleration, injection needle lift, knock detection, engine torque, etc., and with means for the angular coding of the crankshaft position. The control system includes a synchronization set (7) co-operating with angular discrimination means so as to readjust automatically at any time the angular coding data with respect to the combustion cycles. An acquisition set digitizes at a high frequency the various data measured, and notably the pressure values taken during each cycle, simultaneously in all the cylinders. A processing set (18) including notably a fast digital processor suited for determining in real time complex physical parameters such as the man indicated pressure (PMI) at each cycle or each engine revolution, stability factors of these parameters in time, etc. The results obtained are applied to a control computer (19) suited for determining and optimizing various engine parameters such as fuel injection, advanced ignition, etc.

Instantaneous data acquisition and processing system for internal-combustion engine control

The control system according to the invention is associated with an engine provided with means for measuring one or more parameters: pressures (in the cylinder, at intake, at exhaust) for each cylinder, accelerator, injector needle lift, detecting pinking or knocking, engine torque, etc., and with means for angular encoding of the crankshaft position. It includes a synchronisation assembly (7) interacting with means for angular discrimination, so as to reset automatically at every moment the angular encoding data with respect to the combustion cycles. An acquisition assembly digitises, at a high frequency, various data items measured and especially the values of the pressure taken during each cycle, simultaneously in all the cylinders. A processing assembly (18) especially comprising a fast digital processor suitable for determining in real time complex physical parameters such as indicated MEP (mean effective pressure) over each cycle or engine revolution, factors of stability of these parameters over time etc. The results obtained are applied to a control computer (19) designed to determine and optimise various parameters of the engine: fuel injection, ignition advance, etc. - Application to optimising two-stroke or four-stroke petrol or diesel engines.

System for the acquisition and instantaneous processing of data for the control of an internal combustion engine

PRECIS DE LA DIVULGATION: Le systeme de commande selon l'invention est associe a un moteur pourvu de moyens de mesure d'un ou plusieurs parametres: pressions (dans le cylindre, a l'admission, a l'echappement) pour chaque cylindre, acceleration, levee d'aiguille d'injecteurs, detection de cliquetis, couple moteur etc, et de moyens de codage angulaire de la position du vilebrequin. Il comporte un ensemble de synchronisation cooperant avec des moyens de discrimination angulaire, de facon a recaler automatiquement a tout instant les donnees de codage angulaire par rapport aux cycles de combustion. Un ensemble d'acquisition numerise avec une frequence elevee differentes donnees mesurees et notamment les valeurs de la pression prises au cours de chaque cycle, simultanement dans tous les cylindres. Un ensemble de traitement comprenant notamment un processeur numerique rapide adapte a determiner en temps reel des parametres physiques complexes tels que la PMI (pression moyenne indiquee) sur chaque cycle ou chaque tour moteur, facteurs de stabilite de ces parametres dans le temps etc. Les resultats obtenus sont appliques a un calculateur de commande adapte a determiner et optimiser differents parametres du moteur: injection de carburant, avance a l'allumage etc. Application a l'optimisation de moteurs a 2 ou 4 temps a essence ou diesel.

Michel Rivaud

Papers

Instantaneous data acquisition and processing system for internal-combustion engine control

System for the acquisition and instantaneous processing of data for the control of an internal combustion engine

Système d'acquisition et de traitement instantané de données pour le contrôle d'un moteur à combustion interne.