Method and apparatus for torque control of an internal combustion engine as a function of exhaust smoke level

摘要

A method and apparatus are provided for controlling the torque or fuel quantity limit to an internal combustion engine such as a diesel engine, at least partly as a function of the sensed level of smoke in the exhaust gas stream of the engine. An open-loop preliminary fuel quantity limit signal is provided as a function of engine speed. The actual smoke level is compared with a smoke limit value for the particular operating condition, and an error signal indicates the sense and possibly the magnitude of any difference. The error signal is the basis of a compensating signal which is added to the open-loop preliminary fuel quantity limit signal such that the resulting fuel quantity limit signal provides for maximum torque without exceeding the smoke limit. The smoke level is obtained by a direct measurement of the particulate level or the like in the exhaust gas stream. An alarm may be provided for indicating when the actual smoke level exceeds some threshold relative to the smoke limit.