System and method for controlling exhaust gas temperature

A method comprising:

• determining an air density value for an inlet of an air compressor, the air compressor positioned at an inlet side of an internal combustion engine of an engine system;
• identifying, from two or more ranges of air density values, a range of air density values that encompasses the determined air density value;
• selecting, using the identified range of air density values, an engine speed and engine power relationship from a plurality of engine speed and engine power relationships, the selected engine speed and engine power relationship corresponding to an engine speed and an engine power to be achieved by operation of the internal combustion engine to attain a target exhaust gas temperature;
• and
• attaining the target exhaust gas temperature by at least adjusting at least one of the engine speed and the engine power using information from the selected engine speed and engine power relationship.

A method comprising:

• determining an air-fuel ratio for an engine of an engine system;
• modifying a relationship between an engine speed and an outputted engine power as a function of the determined air-fuel ratio;
• and
• adjusting at least one of the engine speed and the outputted engine power using the modified relationship between the engine speed and the outputted engine power to attain a target exhaust gas temperature at an inlet of a selective catalytic reduction system of the engine system.