Control system for compression-ignition engine

A control system for a compression-ignition engine, comprising:

• an engine having a combustion chamber formed by a cylinder, a piston and a cylinder head;
• an injector attached to the engine and configured to supply fuel into the combustion chamber;
• a spark plug disposed to be oriented into the combustion chamber;
• a swirl valve provided to an intake passage of the engine;
• and
• a controller connected to the injector, the spark plug, and the swirl valve and configured to output a control signal to the injector, the spark plug, and the swirl valve, respectively, the controller including a processor configured to execute:
• a swirl adjusting module configured to change an opening of the swirl valve, the swirl adjusting module outputting a control instruction to the injector to inject the fuel after a control of the swirl valve;
• and
• a combustion controlling module to output an ignition instruction to the spark plug so as to ignite at a given ignition timing after an exhaust gas recirculation (EGR) ratio adjustment, so that partial compression-ignition combustion in which a mixture gas combusts by flame propagation and then combusts by compression ignition within a predetermined partial compression-ignition combustion operating range, is performed,
• wherein the swirl adjusting module outputs a control instruction to the swirl valve to make the opening of the swirl valve smaller as an engine load decreases within the partial compression-ignition combustion operating range, and make the opening of the swirl valve smaller as an engine speed decreases within the partial compression-ignition combustion operating range.