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.